Disdrometer and Tipping Bucket Rain Gauge Handbook
Bartholomew. MJ
2009-12-01T23:59:59.000Z
The Distromet disdrometer model RD-80 and NovaLynx tipping bucket rain gauge model 260-2500E-12 are two devices deployed a few meters apart to measure the character and amount of liquid precipitation. The main purpose of the disdrometer is to measure drop size distribution, which it does over 20 size classes from 0.3 mm to 5.4 mm. The data from both instruments can be used to determine rain rate. The disdrometer results can also be used to infer several properties including drop number density, radar reflectivity, liquid water content, and energy flux. Two coefficients, N0 and ?, from an exponential fit between drop diameter and drop number density, are routinely calculated. Data are collected once a minute. The instruments make completely different kinds of measurements. Rain that falls on the disdrometer sensor moves a plunger on a vertical axis. The disdrometer transforms the plunger motion into electrical impulses whose strength is proportional to drop diameter. The rain gauge is the conventional tipping bucket type. Each tip collects an amount equivalent to 0.01 in. of water, and each tip is counted by a data acquisition system anchored by a Campbell CR1000 data logger.
Optical Rain Gauge and Tipping Bucket Rain Gauge Comparisons
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5(Million Cubic Feet) Oregon (Including Vehicle Fuel) (Million Cubic Feet) NaturalOctober OctoberResolved:Operations buildingcapabilitiesRain Gauge and
in revised form 18 October 2013 Accepted 8 November 2013 Rain gauges and weather radars do not measure some usual practice. © 2013 Elsevier B.V. All rights reserved. Keywords: Radarrain gauge comparison are tipping bucket rain gauges, disdrometers, weather radars and (passive or active) sensors onboard
Troch, Peter
events. Using weather radar observations and a dense network of 40 tipping bucket rain gauges, this studyMulticriteria design of rain gauge networks for flash flood prediction in semiarid catchments. [1] Despite the availability of weather radar data at high spatial (1 km2 ) and temporal (515 min
Why we started a Volunteer Rain Gauge Network
Collett Jr., Jeffrey L.
in their backyards #12;4-inch diameter High capacity rain gauges Aluminum foil-wrapped Styrofoam hail pads Snow
Climatology of extreme rainfall from rain gauges and weather radar
Stoffelen, Ad
by conventional rain gauge networks. A 10-year radar-based climatology of rainfall depths for durations of 15 minClimatology of extreme rainfall from rain gauges and weather radar Aart Overeem #12;Thesis:30 PM in the Aula #12;Aart Overeem Climatology of extreme rainfall from rain gauges and weather radar
DOE/SC-ARM/TR-079 Disdrometer and Tipping Bucket Rain Gauge
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article)41clothThe Bonneville Power Administration would likeCustomerComments SignUtah Image.0ATTACHMENTS February2 Disdrometer
Comparing TRMM rainfall retrieval with NOAA buoy rain gauge data
Phillips, Amy Blackmore
2002-01-01T23:59:59.000Z
to December of 2001. TRMM's 3G68 product provides instantaneous rain rate data averaged over 0.5? x 0.5? latitude-longitude grid boxes for the TRMM Microwave Imager (TMI), Precipitation Radar (PR), and a combined algorithm (COMB). The buoy's rain rate data...
Sexton, Aisha M.; Sadeghi, Ali M.; Zhang, Xuesong; Srinivasan, Ragahvan; Shirmohammadi, Adel
2010-05-10T23:59:59.000Z
The value of watershed?scale, hydrologic and water quality models to ecosystem management is increasingly evident as more programs adopt these tools to evaluate the effectiveness of different management scenarios and their impact on the environment. Quality of precipitation data is critical for appropriate application of watershed models. In small watersheds, where no dense rain gauge network is available, modelers are faced with a dilemma to choose between different data sets. In this study, we used the German Branch (GB) watershed (~50 km2), which is included in the USDA Conservation Effects Assessment Project (CEAP), to examine the implications of using surface rain gauge and next?generation radar (NEXRAD) precipitation data sets on the performance of the Soil and Water Assessment Tool (SWAT). The GB watershed is located in the Coastal Plain of Maryland on the eastern shore of Chesapeake Bay. Stream flow estimation results using surface rain gauge data seem to indicate the importance of using rain gauges within the same direction as the storm pattern with respect to the watershed. In the absence of a spatially representative network of rain gauges within the watershed, NEXRAD data produced good estimates of stream flow at the outlet of the watershed. Three NEXRAD datasets, including (1)*non?corrected (NC), (2) bias?corrected (BC), and (3) inverse distance weighted (IDW) corrected NEXRAD data, were produced. Nash?Sutcliffe efficiency coefficients for daily stream flow simulation using these three NEXRAD data ranged from 0.46 to 0.58 during calibration and from 0.68 to 0.76 during validation. Overall, correcting NEXRAD with rain gauge data is promising to produce better hydrologic modeling results. Given the multiple precipitation datasets and corresponding simulations, we explored the combination of the multiple simulations using Bayesian model averaging.
DeMoss, Jeremy
2009-06-02T23:59:59.000Z
in precipitation retrievals from the satellite data alone. We estimate changes in TRMM Microwave Imager (TMI) and the Precipitation Radar (PR) precipitation retrievals due to the orbit boost by comparing them with surface rain gauges on ocean buoys operated...
Jendrowski, P.; Kelly, D. S.; Klazura, G. E.; Thomale, J. M.
1999-04-14T23:59:59.000Z
Rain gauge measurements were compared with radar-estimated storm total precipitation for 43 rain events that occurred at ten locations. Gauge-to-radar ratios (G/R) were computed for each case. The G/R ratio is strongly related to precipitation type, with the mean G/R slightly less than 1.00 for high-reflectivity gradient cases and greater than 2.00 (factor of 2 radar underestimation) for low-reflectivity gradient cases. both precipitation types indicated radar underestimate at the nearest ranges. However, the high-reflectivity gradient cases indicated radar overestimation at further ranges, while the low-reflectivity gradient cases indicated significant radar underestimation at all ranges. Occurrences of radar overestimates may have been related to high reflectivity returns from melting ice, bright-band effects in stratiform systems and hail from convective systems. Bright-band effects probably were responsible for improving the radar underestimates in the second range interval (50-99.9 km) for the low-reflectivity gradient cases. Other possibilities for radar overestimates are anomalous propagation (AP) of the radar beam. Smith, et al. (1996) concluded that bright band and AP lead to systematic overestimate of rainfall at intermediate ranges.
Rutledge, Steven
An Examination of Version 5 Rainfall Estimates from the TRMM Microwave Imager, Precipitation Radar, and Rain Gauges on Global, Regional, and Storm Scales STEPHEN W. NESBITT1 AND EDWARD J. ZIPSER Department Current affiliation: Radar Meteorology Group, Department of Atmospheric Science, Colorado State University
Bhat, C.M.; /Fermilab
2011-03-01T23:59:59.000Z
The Recycler Ring at Fermilab uses a barrier rf systems for all of its rf manipulations. In this paper, I will give an overview of historical perspective on barrier rf system, the longitudinal beam dynamics issues, aspects of rf linearization to produce long flat bunches and methods used for emittance measurements of the beam in the RR barrier rf buckets. Current rf manipulation schemes used for antiproton beam stacking and longitudinal momentum mining of the RR beam for the Tevatron collider operation are explained along with their importance in spectacular success of the Tevatron luminosity performance.
Rub link assembly for dragline bucket
Briscoe, T.L.
1987-09-01T23:59:59.000Z
A rub link assembly is described for a dragline bucket adapted to be interconnected in a hoist chain for rolling movement against the bucket side comprising a relatively elongated member having a clevis at each end, each clevis being equipped with aligned openings adapted to receive bolt means for removably connecting the clevis to the hoist chain links. The member is equipped with a cylindrical collar journaled thereon between the clevises and providing a rolling bearing against the bucket side.
Turbine bucket natural frequency tuning rib
Wang, John Zhiqiang (Greenville, SC); Norton, Paul Francis (Greenville, SC); Barb, Kevin Joseph (Halfmoon, NY); Jacala, Ariel Caesar-Prepena (Simpsonville, SC)
2002-01-01T23:59:59.000Z
A tuning rib is added preferably in the aft cavity of a cored turbine bucket to alter the bucket's natural frequencies. The tuning rib may be a solid rib or a segmented rib and is particularly suited for altering high order frequency modes such as 2T, 4F and 1-3S. As such, detrimental crossings of natural bucket frequencies and gas turbine stimuli can be avoided to thereby improve the reliability of a gas turbine without impacting other features of the bucket that are important to the performance of the gas turbine.
Prototype bucket foundation for wind turbines
Prototype bucket foundation for wind turbines -natural frequency estimation Lars Bo Ibsen Morten bucket foundation for wind turbines -natural frequency estimation by Lars Bo Ibsen Morten Liingaard foundation for wind turbines--natural frequency estimation" is divided into four numbered sections
Safety for an Autonomous Bucket Excavator During Typical Landscaping
Berns, Karsten
Safety for an Autonomous Bucket Excavator During Typical Landscaping Tasks Gregor Zolynski, Daniel the goal of automating a mobile bucket excavator for excavation and loading tasks. This document contains a short introduction to the autonomous bucket excavator THOR, a concept for low-level safety using laser
Liquid cooled counter flow turbine bucket
Dakin, James T. (Schenectady, NY)
1982-09-21T23:59:59.000Z
Means and a method are provided whereby liquid coolant flows radially outward through coolant passages in a liquid cooled turbine bucket under the influence of centrifugal force while in contact with countercurrently flowing coolant vapor such that liquid is entrained in the flow of vapor resulting in an increase in the wetted cooling area of the individual passages.
Stability of barrier buckets with zero RF-barrier separations
Ng, K.Y.; /Fermilab
2005-03-01T23:59:59.000Z
A barrier bucket with very small separation between the rf barriers (relative to the barrier widths) or even zero separation has its synchrotron tune decreasing rather slowly from a large value towards the boundary of the bucket. As a result, large area at the bucket edges can become unstable under the modulation of rf voltage and/or rf phase. In addition, chaotic regions may form near the bucket center and extend outward under increasing modulation. Application is made to those barrier buckets used in the process of momentum mining at the Fermilab Recycler Ring.
Third-stage turbine bucket airfoil
Pirolla, Peter Paul (Greenville, SC); Siden, Gunnar Leif (Greenville, SC); Humanchuk, David John (Simpsonville, SC); Brassfield, Steven Robert (Cincinnati, OH); Wilson, Paul Stuart (New Richmond, OH)
2002-01-01T23:59:59.000Z
The third-stage buckets have airfoil profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in inches in Table I wherein Z is a perpendicular distance from a plane normal to a radius of the turbine centerline and containing the X and Y values with the Z value commencing at zero in the X, Y plane at the radially innermost aerodynamic section of the airfoil and X and Y are coordinates defining the airfoil profile at each distance Z. The X, Y and Z values may be scaled as a function of the same constant or number to provide a scaled-up or scaled-down airfoil section for the bucket.
Bucket Hashing and its Application to Fast Message Authentication
Bernstein, Daniel
the contents of each bucket; then collect up all the buckets' contents. Used in the context of Wegman to authenticate. But it is wellknown that this reasoning is specious: in particular, Wegman and Carter [32. In the Wegman--Carter approach communicating parties S and V share a secret key k = (h; P ) which specifies both
Bucket Hashing and its Application to Fast Message Authentication
Rogaway, Phillip
the contents of each bucket; then collect up all the buckets' contents. Used in the context of Wegman. But it is well-known that this reasoning is specious: in particular, Wegman and Carter [32] showed back in 1981 that we do not have to "cryptographically" transform the entire string x. In the WegmanCarter approach
Bucket Hashing and its Application to Fast Message Authentication
California at Davis, University of
the contents of each bucket then collect up all the buckets' contents. Used in the context of Wegman. But it is well-known that this reasoning is specious: in particular, Wegman and Carter 32] showed back in 1981 that we do not have to \\cryptographically" transform the entire string x. In the Wegman{Carter approach
Airfoil shape for a turbine bucket
Hyde, Susan Marie; By, Robert Romany; Tressler, Judd Dodge; Schaeffer, Jon Conrad; Sims, Calvin Levy
2005-06-28T23:59:59.000Z
Third stage turbine buckets have airfoil profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth Table I wherein X and Y values are in inches and the Z values are non-dimensional values from 0 to 0.938 convertible to Z distances in inches by multiplying the Z values by the height of the airfoil in inches. The X and Y values are distances which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z. The profile sections at each distance Z are joined smoothly to one another to form a complete airfoil shape. The X and Y distances may be scalable as a function of the same constant or number to provide a scaled up or scaled down airfoil section for the bucket. The nominal airfoil given by the X, Y and Z distances lies within an envelop of .+-.0.150 inches in directions normal to the surface of the airfoil.
Xie, Hongjie; Zhang, Xuesong; Yu, Beibei; Sharif, Hatim
2011-04-21T23:59:59.000Z
High spatial and temporal resolution of precipitation data is critical input for hydrological budget estimation and flash flood modeling. This study evaluated four methods (Bias Adjustment (BA), Simple Kriging with varying Local Means (SKlm), Kriging with External Drift (KED), and Regression Kriging (RK)) for their performances in incorporating gauge rainfall measurements into NEXRAD (Next Generation Weather Radar) Multisensor Precipitation Estimator (MPE) (hourly and 4 x 4 km{sup 2}). Measurements from a network of 50 gauges at the Upper Guadalupe River Basin, Central Texas and MPE data for the year 2004 were used in the study. We used three evaluation coefficients Percentage Bias (PB), Coefficient of Determination (R2), and Nash-Sutcliffe efficiency (NSE) to examine the performance of the four methods for preserving regional and local scale characteristics of observed precipitation data. The results show that the two Kriging-based methods (SKlm and RK) are in generally better than BA and KED and that the PB and NSE criteria are better than the R2 criterion in assessing the performance of the four methods. It is also worth noting that the performance of one method at regional scale may be different from its performance at local scale. Critical evaluation of the performance of different methods at local or regional scale should be conducted according to the different purposes. The results obtained in this study are expected to contribute to the development of more accurate spatial rainfall products for hydrologic budget and flash flood modeling.
Cooling circuit for a gas turbine bucket and tip shroud
Willett, Fred Thomas (25 Long Creek Dr., Burnt Hills, NY 12027); Itzel, Gary Michael (12 Cider Mill Dr., Clifton Park, NY 12065); Stathopoulos, Dimitrios (11 Wyngate Rd., Glenmont, NY 12077); Plemmons, Larry Wayne (late of Hamilton, OH); Plemmons, Helen M. (2900 Long Ridge Trails, Hamilton, OH 45014); Lewis, Doyle C. (444 River Way, Greer, SC 29651)
2002-01-01T23:59:59.000Z
An open cooling circuit for a gas turbine bucket wherein the bucket has an airfoil portion, and a tip shroud, the cooling circuit including a plurality of radial cooling holes extending through the airfoil portion and communicating with an enlarged internal area within the tip shroud before exiting the tip shroud such that a cooling medium used to cool the airfoil portion is subsequently used to cool the tip shroud.
Removable inner turbine shell with bucket tip clearance control
Sexton, Brendan F. (Clifton Park, NY); Knuijt, Hans M. (Niskayuna, NY); Eldrid, Sacheverel Q. (Saratoga Springs, NY); Myers, Albert (Amsterdam, NY); Coneybeer, Kyle E. (Schenectady, NY); Johnson, David Martin (Ballston Lake, NY); Kellock, Iain R. (Clifton Park, NY)
2000-01-01T23:59:59.000Z
A turbine includes a plurality of inner shell sections mounting first and second stage nozzle and shroud portions. The inner shell sections are pinned to an outer containment shell formed of sections to preclude circumferential movement of the inner shell relative to the outer shell and enable thermal expansion and contraction of the inner shell relative to the outer shell. Positive bucket tip clearance control is afforded by passing a thermal medium about the inner shell in heat transfer relation with the shrouds about the first and second stage bucket tips, the thermal medium being provided from a source of heating/cooling fluid independent of the turbine. Access is provided to the rotor and turbine buckets by removing the outer and inner shell sections.
First-stage high pressure turbine bucket airfoil
Brown, Theresa A.; Ahmadi, Majid; Clemens, Eugene; Perry, II, Jacob C.; Holiday, Allyn K.; Delehanty, Richard A.; Jacala, Ariel Caesar
2004-05-25T23:59:59.000Z
The first-stage buckets have airfoil profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein Z is a perpendicular distance from a plane normal to a radius of the turbine centerline and containing the X and Y values with the Z value commencing at zero in the X, Y plane at the radially innermost aerodynamic section of the airfoil and X and Y are coordinates defining the airfoil profile at each distance Z. The X, Y and Z values may be scaled as a function of the same constant or number to provide a scaled-up or scaled-down airfoil section for the bucket.
Cavaleri, Luigi; Bidlot, Jean-Raymond
2015-01-01T23:59:59.000Z
We consider the effect of rain on wind wave generation and dissipation. Rain falling on a wavy surface may have a marked tendency to dampen the shorter waves in the tail of the spectrum, the related range increasing with the rain rate. Following the coupling between meteorological and wave models, we derive that on the whole this should imply stronger wind and higher waves in the most energetic part of the spectrum. This is supported by numerical experiments. However, a verification based on the comparison between operational model results and measured data suggests that the opposite is true. This leads to a keen analysis of the overall process, in particular on the role of the tail of the spectrum in modulating the wind input and the white-capping. We suggest that the relationship between white-capping and generation by wind is deeper and more implicative than presently generally assumed.
Nelson, D.A.; Tomich, S.D.; Glover, D.W.; Allen, E.V.; Hales, J.M.; Dana, M.T.
1991-05-14T23:59:59.000Z
The present invention constitutes a rain sampling device adapted for independent operation at locations remote from the user which allows rainfall to be sampled in accordance with any schedule desired by the user. The rain sampling device includes a mechanism for directing wet precipitation into a chamber, a chamber for temporarily holding the precipitation during the process of collection, a valve mechanism for controllably releasing samples of the precipitation from the chamber, a means for distributing the samples released from the holding chamber into vessels adapted for permanently retaining these samples, and an electrical mechanism for regulating the operation of the device. 11 figures.
Behavior-based trajectory adaptation based on bucket-volume estimation
Berns, Karsten
Outdoor Robot). Long-term goal of this project is to develop a fully autonomous bucket excavator which project is to create a fully autonomous bucket excavator which is capable of performing landscaping tasks on a construction site [1]. Figure 1 shows a picture of the automated 18-ton wheeled excavator test platform. CVT
Prof. Dr. Karsten Berns The long term-goal of the autonomous bucket excavator project is
Berns, Karsten
29/03/2012 Prof. Dr. Karsten Berns The long term-goal of the autonomous bucket excavator project is the development of a fully autonomous wheeled excavator which is able to perform landscaping tasks in a real application scenario. As the input from the control system is a desired pose of the bucket, a new behaviour
Supercinski, Danielle
2006-01-01T23:59:59.000Z
tx H2O | pg. 19 West Texas Rain Story by Danielle Supercinski Rainwater, one of the purest sources of wateravailable, is scarce in West Texas. Residentsin this arid land must use all availablemethods of saving water. Rainwater har- vesting, a... in West Texas to educate the public about its potential as an alternative and inexpensive source of high-quality water. Most rainwater harvesting systems in the past were for personal use, but some businesses, industries and public institutions...
Prof. Dr. Karsten Berns The long term-goal of the autonomous bucket excavator project is
Berns, Karsten
29/03/2012 Prof. Dr. Karsten Berns The long term-goal of the autonomous bucket excavator project is the development of a fully autonomous wheeled excavator which is able to perform landscaping tasks in a real
Gated current integrator for the beam in the RR barrier buckets
A. Cadorn; C. Bhat; J. Crisp
2003-06-10T23:59:59.000Z
At the Fermilab Recycler Ring (RR), the antiproton (pbar) beam will be stored azimuthally in different segments created by barrier buckets. The beam in each segment may have widely varying intensities. They have developed a gated integrator system to measure the beam intensity in each of the barrier bucket. Here they discuss the design of the system and the results of beam measurements using the integrator.
Jumping into buckets, or How to decontaminate overlapping fat jets
Koichi Hamaguchi; Seng Pei Liew; Martin Stoll
2015-05-12T23:59:59.000Z
At the LHC, tagging boosted heavy particle resonances which decay hadronically, such as top quarks and Higgs bosons, can play an essential role in new physics searches. In events with high multiplicity, however, the standard approach to tag boosted resonances by a large-radius fat jet becomes difficult because the resonances are not well-separated from other hard radiation. In this paper, we propose a different approach to tag and reconstruct boosted resonances by using the recently proposed mass-jump jet algorithm. A key feature of the algorithm is the flexible radius of the jets, which results from a terminating veto that prevents the recombination of two hard prongs if their combined jet mass is substantially larger than the masses of the separate prongs. The idea of collecting jets in "buckets" is also used. As an example, we consider the fully hadronic final state of pair-produced vectorlike top partners at the LHC, $pp\\to T\\bar{T}\\to t\\bar{t}HH$, and show that the new approach works better than the corresponding generalized $k_T$ jet clustering algorithm. We also show that tagging and kinematic reconstruction of boosted top quarks and Higgs bosons are possible with good quality even in these very busy final states. The vectorlike top partners are kinematically reconstructed, which allows their direct mass measurement.
Jumping into buckets, or How to decontaminate overlapping fat jets
Hamaguchi, Koichi; Stoll, Martin
2015-01-01T23:59:59.000Z
At the LHC, tagging boosted heavy particle resonances which decay hadronically, such as top quarks and Higgs bosons, can play an essential role in new physics searches. In events with high multiplicity, however, the standard approach to tag boosted resonances by a large-radius fat jet becomes difficult because the resonances are not well-separated from other hard radiation. In this paper, we propose a different approach to tag and reconstruct boosted resonances by using the recently proposed mass-jump jet algorithm. A key feature of the algorithm is the flexible radius of the jets, which results from a terminating veto that prevents the recombination of two hard prongs if their combined jet mass is substantially larger than the masses of the separate prongs. The idea of collecting jets in "buckets" is also used. As an example, we consider the fully hadronic final state of pair-produced vectorlike top partners at the LHC, $pp\\to T\\bar{T}\\to t\\bar{t}HH$, and show that the new approach works better than the corr...
Controlling acid rain : policy issues
Fay, James A.
1983-01-01T23:59:59.000Z
The policy and regulatory ramifications of U.S. acid rain control programs are examined; particularly, the alternative of a receptor-oriented strategy as constrasted to emission-oriented proposals (e.g., the Mitchell bill) ...
Berns, Karsten
Behavior-based Arm Control for an Autonomous Bucket Excavator Sergey Pluzhnikov, Daniel Schmidt control value to solve the global problem. By means of controlling a wheeled excavator robot arm autonomous bucket excavator. A key func- tionality of such a system is autonomous landscaping according
Turbine bucket for use in gas turbine engines and methods for fabricating the same
Garcia-Crespo, Andres
2014-06-03T23:59:59.000Z
A turbine bucket for use with a turbine engine. The turbine bucket includes an airfoil that extends between a root end and a tip end. The airfoil includes an outer wall that defines a cavity that extends from the root end to the tip end. The outer wall includes a first ceramic matrix composite (CMC) substrate that extends a first distance from the root end to the tip end. An inner wall is positioned within the cavity. The inner wall includes a second CMC substrate that extends a second distance from the root end towards the tip end that is different than the first distance.
Prof. Dr. Karsten Berns The long term-goal of the autonomous bucket excavator project
Berns, Karsten
10/01/2013 Prof. Dr. Karsten Berns The long term-goal of the autonomous bucket excavator project T.H.O.R. (Terraforming Heavy Outdoor Robot) is the development of a fully autonomous wheeled excavator which is able of the excavator boom and it's capability to influence the environment. By installing new sensors and actuators
Gladwell, John Stuart
1961-01-01T23:59:59.000Z
and the effects of gravity forces are ignored. Some other bases of sxmx1itude are: (1) Weber Number; used when surf'ace tension effects predoxninate, (2) Mach Number; used when forces involve elastic com- pression; e. g. , water-hammer effect, (3) Cavitation.... Vertical distance between any two points on the spillway, ft. INTRODUCTION The ski-jump spillway is an arrangexnent by which a flow of water is carried down a chute to a slightly upturned lip (forming a bucket) that throws the jet out over a pool below...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article) |govInstrumentsmfrirt Documentation ARM DatagovInstrumentsuhsas Documentation ARMInstruments RelatedBarrow,PlansAcid Rain
Sparks, William Joseph
1992-01-01T23:59:59.000Z
fire, a woodchip flaring in his cupped palm as he passed. A fireman had come out after Brusher from the entrance of the fire temple across the way. The king summarily returned the enchanted wave of the man-boy, whose longish face became doubly...
Acid rain information book. Draft final report
None
1980-12-01T23:59:59.000Z
Acid rain is one of the most widely publicized environmental issues of the day. The potential consequences of increasingly widespread acid rain demand that this phenomenon be carefully evaluated. Reveiw of the literature shows a rapidly growing body of knowledge, but also reveals major gaps in understanding that need to be narrowed. This document discusses major aspects of the acid rain phenomenon, points out areas of uncertainty, and summarizes current and projected research by responsible government agencies and other concerned organizations.
Paris-Sud XI, Université de
variability on standard comparison tools between radar and rain gauge data. Submitted to Atm. Res. Schertzer D Rainfall point measurements: - Tipping bucket rain gauges (usually 0.2 mm tips) -Disdrometers (binned size rate (Total depth ~ 30 mm) Temporal evolution of N(D) Avg N(D) (m-3mm-1) (in log) = 2.66 = max min
Rain, Rain, Don't Go Away Taking a 360-Degree View of Water
Christian, Eric
Rain, Rain, Don't Go Away Taking a 360-Degree View of Water The Science of Photography National Flood Studies Field Campaign 6 Taking a 360-Degree View of Water 8 From GLOBE Star Student to GLOBE
Betts, Robert E.; Crawford, John F.
1989-04-04T23:59:59.000Z
An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.
Betts, Robert E. (Huntsville, AL); Crawford, John F. (Huntsville, AL)
1989-01-01T23:59:59.000Z
An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.
WIND/RAIN BACKSCATTER MODELING AND WIND/RAIN RETRIEVAL FOR SCATTEROMETER AND
Long, David G.
WIND/RAIN BACKSCATTER MODELING AND WIND/RAIN RETRIEVAL FOR SCATTEROMETER AND SYNTHETIC APERTURE. Fulton College of Engineering and Technology #12;#12;ABSTRACT WIND/RAIN BACKSCATTER MODELING AND WIND- surements, and numerical predicted wind fields (ECMWF), the sensitivity of C-band backscatter measurement
The Effect of Rain on ERS Scatterometer Measurements
Long, David G.
measurements in rainy conditions [1] [2]. In a raining area, rain striking the water surface creates splashThe Effect of Rain on ERS Scatterometer Measurements Congling Nie and David G. Long Department evidence of rain surface per- turbation in recent studies of surface radar backscatter, the rain effects
Cooling supply system for stage 3 bucket of a gas turbine
Eldrid, Sacheverel Quentin (Saratoga Springs, NY); Burns, James Lee (Schenectady, NY); Palmer, Gene David (Clifton Park, NY); Leone, Sal Albert (Scotia, NY); Drlik, Gary Joseph (Fairfield, OH); Gibler, Edward Eugene (Cincinnati, OH)
2002-01-01T23:59:59.000Z
In a land based gas turbine including a compressor, a combustor and turbine section including at least three stages, an improvement comprising an inlet into a third stage nozzle from the compressor for feeding cooling air from the compressor to the third stage nozzle; at least one passageway running substantially radially through each airfoil of the third stage nozzle and an associated diaphragm, into an annular space between the rotor and the diaphragm; and passageways communicating between the annular space and individual buckets of the third stage.
Long range transport of acid rain precursors
Fay, James A.
1983-01-01T23:59:59.000Z
A model of the long range transport of primary and secondary pollutants derived by Fay and Rosenzweig (1) is applied to the problem of the transport of acid rain precursors. The model describes the long term average (annual ...
Atmospheric deposition of ^Be by rain events, in central Argentina
Nacional de San Luis, Universidad
Atmospheric deposition of ^Be by rain events, in central Argentina Juri Ayub, J. , Di Gregorio, B Argentina. Rain traps were installed (1 m above ground) and individual rain events have been collected. Rain efficiency was determined using a water solution with known amounts of chemical compounds containing long
The Monitoring Network of the Vancouver 2010 Olympics BILL SCOTT,1
Houze Jr., Robert A.
, an acoustic snow depth sensor, a Pluvio 1 precipitation gauge and an anemometer placed at gauge height. The sensors included an HMP45C for temperature, humidity and pressure, a tipping bucket rain gauge sampling intervals. A Doppler weather radar was deployed in a valley location and provided critical
Generalizing twisted gauge invariance
Duenas-Vidal, Alvaro; Vazquez-Mozo, Miguel A. [Departamento de Fisica Fundamental, Universidad de Salamanca, Plaza de la Merced s/n, E-37008 Salamanca (Spain)
2009-05-01T23:59:59.000Z
We discuss the twisting of gauge symmetry in noncommutative gauge theories and show how this can be generalized to a whole continuous family of twisted gauge invariances. The physical relevance of these twisted invariances is discussed.
LATTICE GAUGE THEORY 1 Lattice Gauge Theory
Creutz, Michael
a crucial tool for the quantum field the- orist. Applied to the formalism of lattice gauge theory, numerical simulations are providing fundamental quantitative information about the interactions of quarksLATTICE GAUGE THEORY 1 Lattice Gauge Theory Michael Creutz Supercomputers have recently become
Schilke, Peter W. (4 Hempshire Ct., Scotia, NY 12302); Muth, Myron C. (R.D. #3, Western Ave., Amsterdam, NY 12010); Schilling, William F. (301 Garnsey Rd., Rexford, NY 12148); Rairden, III, John R. (6 Coronet Ct., Schenectady, NY 12309)
1983-01-01T23:59:59.000Z
In the method for fabrication of water-cooled composite nozzle and bucket hardware for high temperature gas turbines, a high thermal conductivity copper alloy is applied, employing a high velocity/low pressure (HV/LP) plasma arc spraying process, to an assembly comprising a structural framework of copper alloy or a nickel-based super alloy, or combination of the two, and overlying cooling tubes. The copper alloy is plamsa sprayed to a coating thickness sufficient to completely cover the cooling tubes, and to allow for machining back of the copper alloy to create a smooth surface having a thickness of from 0.010 inch (0.254 mm) to 0.150 inch (3.18 mm) or more. The layer of copper applied by the plasma spraying has no continuous porosity, and advantageously may readily be employed to sustain a pressure differential during hot isostatic pressing (HIP) bonding of the overall structure to enhance bonding by solid state diffusion between the component parts of the structure.
Sediment detachment by rain power Emmanuel J. Gabet
Gabet, Emmanuel "Manny"
, washload, kinematic wave Citation: Gabet, E. J., and T. Dunne, Sediment detachment by rain power, Water, detaching soil particles and displacing water. We use the term, rain power, to describe the rate at whichSediment detachment by rain power Emmanuel J. Gabet Department of Geological Sciences, University
Wang, Shiyao; Zhang, Qi; Zhao, Kang
2015-01-01T23:59:59.000Z
Using the spread of the Ice Bucket Challenge on Twitter as a case study, this research compared the concurrent diffusion patterns of both information and behaviors in online social networks. Individual behaviors in taking the Challenge were detected by applying text mining techniques to millions of tweets. After comparing diffusion dynamics of information and behaviors at the network level, the individual level, and the dyadic level, our analysis revealed interesting differences and interactions between the two diffusion processes and laid foundations for future predictive and prescriptive analytics for information and behavior diffusion in social networks.
Robert B. Raines | National Nuclear Security Administration
National Nuclear Security Administration (NNSA)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports to3,1,50022,3,,0,,6,1,Separation 23Tribal EnergyCatalytic Co - PA 40 FUSRAPChupadera?Life Cycle |Physicist(PA)|Responding toB. Raines |
High temperature pressure gauge
Echtler, J. Paul (Pittsburgh, PA); Scandrol, Roy O. (Library, PA)
1981-01-01T23:59:59.000Z
A high temperature pressure gauge comprising a pressure gauge positioned in fluid communication with one end of a conduit which has a diaphragm mounted in its other end. The conduit is filled with a low melting metal alloy above the diaphragm for a portion of its length with a high temperature fluid being positioned in the remaining length of the conduit and in the pressure gauge.
GARDENSA RAIN GARDEN MANUAL FOR SOUTH CAROLINA As development increases, so
Stuart, Steven J.
#12;Rain gardens should be located in an area to which rain water typically flows. If a depression a storm will produce more than 1 inch of rain in 24 hours, excess water should be able to leave the rain an overflow so that excess water from larger storms can be diverted out of the rain garden. To prevent
Sulfur controls edge closer in acid-rain debate
Not Available
1984-10-04T23:59:59.000Z
The role of airborne sulfur emissions from midwestern and southern coal-fired power plants in exacerbating the acid rain problem is discussed. This problem is discussed from the standpoint of legislation, compliance costs, scrubber performance and cost, and chemistry of acid rains.
Simultaneous Wind and Rain Retrieval for ERS Scatterometer Measurements
Long, David G.
Simultaneous Wind and Rain Retrieval for ERS Scatterometer Measurements Congling Nie and David G on the ESCAT wind-only retrieval has been evaluated. For high incidence angle measurements, the additional scattering of rain causes estimated wind speeds to appear higher than expected. It is also noted
Acid rain - A further look at the evidence
Katzenstein, A.W.
1986-03-01T23:59:59.000Z
There is widespread belief that acid rain is damaging lakes and forests in eastern North America, and that the threat of further damage is severe enough to warrant prompt remedial action. The cause of acid rain, hence ecological damage, is popularly held to be the sulfur dioxide (SO/sub 2/) and nitrogen oxides (NO/sub x/) created by the combustion of fossil fuels. This popular belief rests on a narrow selection of data, and is not substantiated by the broader body of knowledge which is available. Nevertheless, numerous bills have been introduced in Congress proposing large reductions in SO/sub 2/ emissions. For example, the first bill introduced in 1985 was S.52, ''The Acid Rain Control Act of 1985.'' It calls for reducing SO/sub 2/ emissions by 10 million tons annually. While the language of S.52 and similar bills is not specific on causes and effects of acid rain, the testimony before Congressional committees made it clear that the concerns focus on the actual or potential acidification of lakes and soils by acid rain, and actual or potential impacts of acid rain on fish, other aquatic life, trees, crops, and human health. This article assesses the merits of these contentions about acid rain by examining technical evidence that relates SO/sub 2/ emissions to the acidity of rain to actual or potential environmental impacts.
Stellar mixing length theory with entropy rain
Brandenburg, Axel
2015-01-01T23:59:59.000Z
Stellar mixing length theory is modified to include the effects of a nongradient term that originates from the motion of convective elements with entropy perturbations of either sign. It is argued that such a term, first studied by Deardorff in the meteorological context, represents the effects of thin intense downdrafts caused by the rapid cooling in the granulation layer at the top of the convection zone. They transport heat nonlocally, as originally anticipated by Spruit in the 1990s, who describes the convection in the strongly stratified simulations of Stein & Nordlund as entropy rain. Although our model has ill-determined free parameters, it demonstrates that solutions can be found that look similar to the original ones, except that the deeper layers are now Schwarzschild stable, so no giant cells are produced and the typical convective scale is that of granules even at larger depth. Consequences for modeling solar differential, the global dynamo, and sunspots are briefly discussed.
Dictionary of Upriver Halkomelem, Volume I
Galloway, Brent Douglas
2009-01-01T23:59:59.000Z
rain-water drops in a bucket::q'pá:ls rain-water drops in a bucket::~ th'eq'ém. collected rain-water from a drip:: th'q'émelets
Manifestly gauge invariant computations
Stefano Arnone; Antonio Gatti; Tim R. Morris
2002-07-16T23:59:59.000Z
Using a gauge invariant exact renormalization group, we show how to compute the effective action, and extract the physics, whilst manifestly preserving gauge invariance at each and every step. As an example we give an elegant computation of the one-loop SU(N) Yang-Mills beta function, for the first time at finite N without any gauge fixing or ghosts. It is also completely independent of the details put in by hand, e.g. the choice of covariantisation and the cutoff profile, and, therefore, guides us to a procedure for streamlined calculations.
Manifestly gauge invariant computations
Arnone, S; Morris, T R; Arnone, Stefano; Gatti, Antonio; Morris, Tim R.
2002-01-01T23:59:59.000Z
Using a gauge invariant exact renormalization group, we show how to compute the effective action, and extract the physics, whilst manifestly preserving gauge invariance at each and every step. As an example we give an elegant computation of the one-loop SU(N) Yang-Mills beta function, for the first time at finite N without any gauge fixing or ghosts. It is also completely independent of the details put in by hand, e.g. the choice of covariantisation and the cutoff profile, and, therefore, guides us to a procedure for streamlined calculations.
Noel, Bruce W. (Espanola, NM); Borella, Henry M. (Santa Barbara, CA); Cates, Michael R. (Oak Ridge, TN); Turley, W. Dale (Santa Barbara, CA); MacArthur, Charles D. (Clayton, OH); Cala, Gregory C. (Dayton, OH)
1991-01-01T23:59:59.000Z
A heat flux gauge comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator, wherein each thermographic layer comprises a plurality of respective thermographic sensors in a juxtaposed relationship with respect to each other. The gauge may be mounted on a surface with the first thermographic phosphor in contact with the surface. A light source is directed at the gauge, causing the phosphors to luminesce. The luminescence produced by the phosphors is collected and its spectra analyzed in order to determine the heat flux on the surface. First and second phosphor layers must be different materials to assure that the spectral lines collected will be distinguishable.
Unparticle actions and gauge invariance
Ilderton, Anton [School of Mathematics, Trinity College, Dublin 2 (Ireland)
2009-01-15T23:59:59.000Z
We show that the requirement of gauge invariance is not enough to fix the form of interactions between unparticles and gauge fields, thus revealing a wide new class of gauged unparticle actions. Our approach also allows us to construct operators which create gauge invariant colored unparticles. We discuss both their perturbative and nonperturbative properties.
Pietro Silvi; Enrique Rico; Tommaso Calarco; Simone Montangero
2014-10-12T23:59:59.000Z
We present a unified framework to describe lattice gauge theories by means of tensor networks: this framework is efficient as it exploits the high amount of local symmetry content native of these systems describing only the gauge invariant subspace. Compared to a standard tensor network description, the gauge invariant one allows to speed-up real and imaginary time evolution of a factor that is up to the square of the dimension of the link variable. The gauge invariant tensor network description is based on the quantum link formulation, a compact and intuitive formulation for gauge theories on the lattice, and it is alternative to and can be combined with the global symmetric tensor network description. We present some paradigmatic examples that show how this architecture might be used to describe the physics of condensed matter and high-energy physics systems. Finally, we present a cellular automata analysis which estimates the gauge invariant Hilbert space dimension as a function of the number of lattice sites and that might guide the search for effective simplified models of complex theories.
Influence of the zero-rainfall on the assessment of the multifractal parameters A. Gires a,b,
Lovejoy, Shaun
, and consequently of the extremes. This framework enables one to retrieve most of the features observed on radar the established multifractal behavior are quite disturbing, and should therefore be addressed in depth. Although. For instance, for most common tipping bucket rain gauges, three problems are well known that strongly affect
Lin, Kevin K.
Section 8.5 1. A worker on a roof 50 ft above the ground needs to lift a 300 lb bucket of cement the top of the tank. Note: 1 cubic foot water weighs 62.4 lb. 4. A gas station stores its gasoline;5. A gas station stores its gasoline in a tank under the ground. The tank is a cylinder standing in upright
Dimethyl sulfide in the Amazon rain forest
Jardine, Kolby; Yanez-Serrano, A. M.; Williams, J.; Kunert, N.; Jardine, A.; Taylor, T.; Abrell, L.; Artaxo, Paulo; Guenther, Alex B.; Hewitt, C. N.; House, E.; Florentino, A. P.; Manzi, A.; Higuchi, N.; Kesselmeier, J.; Behrendt, T.; Veres, P. R.; Derstroff, B.; Fuentes, J.; Martin, Scot T.; Andreae, M. O.
2015-01-01T23:59:59.000Z
Surface-to-atmosphere emissions of dimethyl sulfide (DMS) may impact global climate 44 through the formation of gaseous sulfuric acid, which can yield secondary sulfate 45 aerosols and contribute to new particle formation. While oceans are generally 46 considered the dominant source of DMS, a shortage of ecosystem observations prevents 47 an accurate analysis of terrestrial DMS sources. Using mass spectrometry, we quantified 48 ambient DMS mixing ratios within and above a primary rainforest ecosystem in the 49 central Amazon Basin in real-time (2010-2011) and at high vertical resolution (2013-50 2014). Elevated but highly variable DMS mixing ratios were observed within the 51 canopy, showing clear evidence of a net ecosystem source to the atmosphere during 52 both day and night in both the dry and wet seasons. Periods of high DMS mixing ratios 53 lasting up to 8 hours (up to 160 ppt) often occurred within the canopy and near the 54 surface during many evenings and nights. Daytime gradients showed mixing ratios (up 55 to 80 ppt) peaking near the top of the canopy as well as near the ground following a rain 56 event. The spatial and temporal distribution of DMS suggests that ambient levels and 57 their potential climatic impacts are dominated by local soil and plant emissions. A soil 58 source was confirmed by measurements of DMS emission fluxes from Amazon soils as 59 a function of temperature and soil moisture. Furthermore, light and temperature 60 dependent DMS emissions were measured from seven tropical tree species. Our study 61 has important implications for understanding terrestrial DMS sources and their role in 62 coupled land-atmosphere climate feedbacks. 63
Noel, B.W.; Borella, H.M.; Cates, M.R.; Turley, W.D.; MacArthur, C.D.; Cala, G.C.
1991-04-09T23:59:59.000Z
A heat flux gauge is disclosed comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator, wherein each thermographic layer comprises a plurality of respective thermographic sensors in a juxtaposed relationship with respect to each other. The gauge may be mounted on a surface with the first thermographic phosphor in contact with the surface. A light source is directed at the gauge, causing the phosphors to luminesce. The luminescence produced by the phosphors is collected and its spectra analyzed in order to determine the heat flux on the surface. First and second phosphor layers must be different materials to assure that the spectral lines collected will be distinguishable. 9 figures.
Gauge transformations in non-perturbative chiral gauge theories
Werner Kerler
2005-07-20T23:59:59.000Z
We reconsider gauge-transformation properties in chiral gauge theories on the lattice observing all pertinent information and show that these properties are actually determined in a general way for any gauge group and for any value of the index. In our investigations we also clarify several related issues.
Peter G. O. Freund
2010-08-24T23:59:59.000Z
Erik Verlinde's proposal of the emergence of the gravitational force as an entropic force is extended to abelian and non-abelian gauge fields and to matter fields. This suggests a picture with no fundamental forces or forms of matter whatsoever.
Chiral Gauge Theory for Graphene
R. Jackiw; S. -Y. Pi
2007-05-04T23:59:59.000Z
We construct a chiral gauge theory to describe fractionalization of fermions in graphene. Thereby we extend a recently proposed model, which relies on vortex formation. Our chiral gauge fields provide dynamics for the vortices and also couple to the fermions.
Heavy pollution suppresses light rain in China: observations and modeling
Qian, Yun; Gong, Daoyi; Fan, Jiwen; Leung, Lai R.; Bennartz, Ralph; Chen, Deliang; Wang, Weiguo
2009-08-15T23:59:59.000Z
Long-term observational data reveal that both the frequency and amount of light rain have decreased in eastern China (EC) for 1956-2005 with high spatial coherency. This is different from the trend of total rainfall observed in EC, which decreases in northern EC and increases in southern EC. To examine the cause of the light rain trends, we analyzed the long-term variability of atmospheric water vapor and its correlation with light rain events. Results show very weak relationships between large-scale moisture transport and light rain in EC. This suggests that light rain trend in EC is not driven by large-scale circulation changes. Because of human activities, pollutant emission has increased dramatically in China for the last few decades, leading to significant reductions in visibility between 1960 and 2000. Cloud-resolving model simulations show that aerosols corresponding to heavily polluted conditions can significantly increase the cloud droplet number concentration (CDNC) and reduce droplet sizes compared to pristine conditions. This can lead to a significant decline in raindrop concentration and delay raindrop formation because smaller cloud droplets are less efficient in the collision and coalescence processes. Together with weaker convection, the precipitation frequency and amount are significantly reduced in the polluted case. Satellite data also reveal higher CDNC and smaller droplet size over polluted land in EC relative to pristine regions, which is consistent with the model results. This evidence suggests that the significantly increased aerosol particles produced by air pollution are at least partly responsible for the decreased light rain events observed in China over the past fifty years.
E. I. Guendelman; J. R. Morris
2003-07-01T23:59:59.000Z
Some of the peculiar electrodynamical effects associated with gauged ``dimension bubbles'' are presented. Such bubbles, which effectively enclose a region of 5d spacetime, can arise from a 5d theory with a compact extra dimension. Bubbles with thin domain walls can be stabilized against total collapse by the entrapment of light charged scalar bosons inside the bubble, extending the idea of a neutral dimension bubble to accommodate the case of a gauged U(1) symmetry. Using a dielectric approach to the 4d dilaton-Maxwell theory, it is seen that the bubble wall is almost totally opaque to photons, leading to a new stabilization mechanism due to trapped photons. Photon dominated bubbles very slowly shrink, resulting in a temperature increase inside the bubble. At some critical temperature, however, these bubbles explode, with a release of radiation.
Wood, Billy E. (Livermore, CA); Groves, Scott E. (Brentwood, CA); Larsen, Greg J. (Brentwood, CA); Sanchez, Roberto J. (Pleasanton, CA)
2006-11-14T23:59:59.000Z
A lightweight, small size, high sensitivity gauge for indirectly measuring displacement or absolute gap width by measuring axial strain in an orthogonal direction to the displacement/gap width. The gap gauge includes a preferably titanium base having a central tension bar with springs connecting opposite ends of the tension bar to a pair of end connector bars, and an elongated bow spring connected to the end connector bars with a middle section bowed away from the base to define a gap. The bow spring is capable of producing an axial strain in the base proportional to a displacement of the middle section in a direction orthogonal to the base. And a strain sensor, such as a Fabry-Perot interferometer strain sensor, is connected to measure the axial strain in the base, so that the displacement of the middle section may be indirectly determined from the measurement of the axial strain in the base.
Gauge Theory of Quantum Gravity
J. W. Moffat
1994-01-04T23:59:59.000Z
A gauge theory of quantum gravity is formulated, in which an internal, field dependent metric is introduced which non-linearly realizes the gauge fields on the non-compact group $SL(2,C)$, while linearly realizing them on $SU(2)$. Einstein's $SL(2,C)$ invariant theory of gravity emerges at low energies, since the extra degrees of freedom associated with the quadratic curvature and the internal metric only dominate at high energies. In a fixed internal metric gauge, only the the $SU(2)$ gauge symmetry is satisfied, the particle spectrum is identified and the Hamiltonian is shown to be bounded from below. Although Lorentz invariance is broken in this gauge, it is satisfied in general. The theory is quantized in this fixed, broken symmetry gauge as an $SU(2)$ gauge theory on a lattice with a lattice spacing equal to the Planck length. This produces a unitary and finite theory of quantum gravity.
John H. Schwarz
1998-09-01T23:59:59.000Z
Superstring theory, and a recent extension called M theory, are leading candidates for a quantum theory that unifies gravity with the other forces. As such, they are certainly not ordinary quantum field theories. However, recent duality conjectures suggest that a more complete definition of these theories can be provided by the large N limits of suitably chosen U(N) gauge theories associated to the asymptotic boundary of spacetime.
Ten utilities receive acid rain bonus allowances from EPA
NONE
1995-12-31T23:59:59.000Z
The United States Environmental Protection Agency (EPA) recently awarded 1,349 acid rain bonus allowances to ten utilities for energy efficiency and renewable energy measures. An allowance licensesthee emission of one ton of sulfur dioxide. A limited number of allowances are allocated to utilities to ensure that emissions will be cut to less than 9 million tons per year.
Gauge Dependence of Gravitational Correction to Running of Gauge Couplings
Artur R. Pietrykowski
2007-02-06T23:59:59.000Z
Recently an interesting idea has been put forward by Robinson and Wilczek that incorporation of quantized gravity in the framework of abelian and nonabelian gauge theories results in a correction to the running of gauge coupling and, in consequence, to increase of the Grand Unification scale and to the asymptotic freedom. In this paper it is shown by explicit calculations that this correction depends on the choice of gauge.
Aerosol control on depth of warm rain in convective clouds Mahen Konwar,1
Daniel, Rosenfeld
Aerosol control on depth of warm rain in convective clouds Mahen Konwar,1 R. S. Maheskumar,1 J. R effective radius (re) increased with distance above cloud base (D). Warm rain became detectable, i.e., rain water content >0.01 g/Kg, at the tops of growing convective clouds when re exceeded 12 mm. The re
Rain-induced subsurface airflow and Lisse effect Haipeng Guo,1
Jiao, Jiu Jimmy
is low, and the maximum water-level rise is less than the maximum air pressure induced by rain and the water table depth. Citation: Guo, H., J. J. Jiao, and E. P. Weeks (2008), Rain-induced subsurface] Water table fluctuation may induce subsurface airflow [Jiao and Li, 2004] and airflow caused by rain
The Power of Rain: Rainfall Variability and Erosion in Cape Verde
Jetten, Victor
. Tom Veldkamp University of Twente ITC dissertation number 217 ITC, P.O. Box 217, 7500 AE Enschede, The Netherlands ISBN: 9789061643432 Printed by: ITC Printing Department, Enschede, The Netherlands © Juan rain has spoken, holds and beats inside my heart The friend rain Old Mom the rain That for so long did
RAIN AND WIND ESTIMATION FROM SEAWINDS IN HURRICANES AT ULTRA HIGH RESOLUTION
Long, David G.
RAIN AND WIND ESTIMATION FROM SEAWINDS IN HURRICANES AT ULTRA HIGH RESOLUTION Brent A. Williams method for estimating wind and rain in hurricanes from SeaWinds at ultra-high resolution is developed. We use a hurricane model to generate prior distributions for the wind speed, wind di- rection, and rain
Photometric Model of a Rain Drop Kshitiz Garg and Shree K. Nayar
Nayar, Shree K.
conditions such as haze and fog, rain drops are large and visible to the naked eye. Each drop refracts and photometric models show that each rain drop behaves like a wide-angle lens that redirects light from a large of rain is highly complex. Unlike the particles that cause other weather conditions such as haze and fog
Carpenter, Linda M.; Dine, Michael; Festuccia, Guido; Ubaldi, Lorenzo [Santa Cruz Institute for Particle Physics and Department of Physics, University of California, Santa Cruz California 95064 (United States)
2009-12-15T23:59:59.000Z
In supersymmetric theories, the presence of axions usually implies the existence of a noncompact, (pseudo)moduli space. In gauge-mediated models, the axion would seem a particularly promising dark matter candidate. The cosmology of the moduli then constrains the gravitino mass and the axion decay constant; the former cannot be much below 10 MeV; the latter cannot be much larger than 10{sup 13} GeV. Axinos, when identifiable, are typically heavy and do not play an important role in cosmology.
Polchinski, Joseph [Kavli Institute for Theoretical Physics
2010-09-01T23:59:59.000Z
Gauge theories, which describe the particle interactions, are well understood, while quantum gravity leads to many puzzles. Remarkably, in recent years we have learned that these are actually dual, the same system written in different variables. On the one hand, this provides our most precise description of quantum gravity, resolves some long-standing paradoxes, and points to new principles. On the other, it gives a new perspective on strong interactions, with surprising connections to other areas of physics. I describe these ideas, and discuss current and future directions.
Gauge theories in noncommutative geometry
Thierry Masson
2012-01-16T23:59:59.000Z
In this review we present some of the fundamental mathematical structures which permit to define noncommutative gauge field theories. In particular, we emphasize the theory of noncommutative connections, with the notions of curvatures and gauge transformations. Two different approaches to noncommutative geometry are covered: the one based on derivations and the one based on spectral triples. Examples of noncommutative gauge field theories are given to illustrate the constructions and to display some of the common features.
Composite turbine bucket assembly
Liotta, Gary Charles; Garcia-Crespo, Andres
2014-05-20T23:59:59.000Z
A composite turbine blade assembly includes a ceramic blade including an airfoil portion, a shank portion and an attachment portion; and a transition assembly adapted to attach the ceramic blade to a turbine disk or rotor, the transition assembly including first and second transition components clamped together, trapping said ceramic airfoil therebetween. Interior surfaces of the first and second transition portions are formed to mate with the shank portion and the attachment portion of the ceramic blade, and exterior surfaces of said first and second transition components are formed to include an attachment feature enabling the transition assembly to be attached to the turbine rotor or disk.
Gauge theories on noncommutative spaces
Albert Schwarz
2000-11-29T23:59:59.000Z
I review my results about noncommutative gauge theories and about the relation of these theories to M(atrix) theory following my lecture on ICMP 2000.
Cometary panspermia explains the red rain of Kerala
Godfrey Louis; A. Santhosh Kumar
2003-10-05T23:59:59.000Z
Red coloured rain occurred in many places of Kerala in India during July to September 2001 due to the mixing of huge quantity of microscopic red cells in the rainwater. Considering its correlation with a meteor airbust event, this phenomenon raised an extraordinary question whether the cells are extraterrestrial. Here we show how the observed features of the red rain phenomenon can be explained by considering the fragmentation and atmospheric disintegration of a fragile cometary body that presumably contains a dense collection of red cells. Slow settling of cells in the stratosphere explains the continuation of the phenomenon for two months. The red cells under study appear to be the resting spores of an extremophilic microorganism. Possible presence of these cells in the interstellar clouds is speculated from its similarity in UV absorption with the 217.5 nm UV extinction feature of interstellar clouds.
A General Systems Theory for Rain Formation in Warm Clouds
A. M. Selvam
2014-08-15T23:59:59.000Z
A cumulus cloud model which can explain the observed characteristics of warm rain formation in monsoon clouds is presented. The model is based on classical statistical physical concepts and satisfies the principle of maximum entropy production. Atmospheric flows exhibit selfsimilar fractal fluctuations that are ubiquitous to all dynamical systems in nature, such as physical, chemical, social, etc and are characterized by inverse power law form for power (eddy energy) spectrum signifying long-range space-time correlations. A general systems theory model for atmospheric flows developed by the author is based on the concept that the large eddy energy is the integrated mean of enclosed turbulent (small scale) eddies. This model gives scale-free universal governing equations for cloud growth processes. The model predicted cloud parameters are in agreement with reported observations, in particular, the cloud dropsize distribution. Rain formation can occur in warm clouds within 30minutes lifetime under favourable conditions of moisture supply in the environment.
1984 issues: gas decontrol, energy tax, acid rain
Betts, M.
1983-12-01T23:59:59.000Z
Energy analysts predict that Congress will propose a limited natural gas deregulation bill, an energy tax to offset budget deficits, and acid rain legislation that will focus on scrubber requirements for boilers. Politics will play an important role in whether legislation materializes since Democrats generally favor federal conservation programs and Republicans want to speed up deregulation. The November election will indicate which direction Congress will lean. (DCK)
Cold cathode vacuum gauging system
Denny, Edward C. (Knoxville, TN)
2004-03-09T23:59:59.000Z
A vacuum gauging system of the cold cathode type is provided for measuring the pressure of a plurality of separate vacuum systems, such as in a gas centrifuge cascade. Each casing is fitted with a gauge tube assembly which communicates with the vacuum system in the centrifuge casing. Each gauge tube contains an anode which may be in the form of a slender rod or wire hoop and a cathode which may be formed by the wall of the gauge tube. The tube is provided with an insulated high voltage connector to the anode which has a terminal for external connection outside the vacuum casing. The tube extends from the casing so that a portable magnet assembly may be inserted about the tube to provide a magnetic field in the area between the anode and cathode necessary for pressure measurements in a cold cathode-type vacuum gauge arrangement. The portable magnetic assembly is provided with a connector which engages the external high voltage terminal for providing power to the anode within in the gauge tube. Measurement is made in the same manner as the prior cold cathode gauges in that the current through the anode to the cathode is measured as an indication of the pressure. By providing the portable magnetic assembly, a considerable savings in cost, installation, and maintenance of vacuum gauges for pressure measurement in a gas centrifuge cascade is realizable.
Chen, Jiquan
water sources derived from small (rain events, A. ordosia took advantage of deeper soil waterSummer rain pulse size and rainwater uptake by three dominant desert plants in a desertified composition, Rain pulse size, Summer precipitation Abstract To examine the different effects of rain pulse
Automated Rain Sampler for Real time pH and Conductivity Measurements
Weerasinghe, R; Jayananda, M K; Sonnadara, D U J
2015-01-01T23:59:59.000Z
To monitor the acidity of rain water in real time, a rain water sampling system was developed. The rain sampler detects the initial rain after a dry spell and collects a water sample. Before performing the measurements, the pH probe is calibrated using a standard buffer solution whereas the conductivity probe is calibrated using deionized water. After calibrating the probes the pH and the conductivity of the collected rain water sample are measured using the pH and the conductivity probe. Weather parameters such as air temperature, humidity and pressure are also recorded simultaneously. The pH and conductivity measurement data including weather parameters are transmitted to central station using a GSM modem for further analysis. The collected rain water sample is preserved at the remote monitoring station for post chemical analysis. A programmable logic controller controls the entire process.
Rain or Shine: We Cycle for Science | Department of Energy
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousPlasma |EfficiencyCR-B-99-02Contact on2009: ChuOverview ofPermitProgram ManagementRREEEU.informationRain or
Rains County, Texas: Energy Resources | Open Energy Information
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onsource History View New Pagessource HistoryRAPID/Roadmap/6-CO-bRoadmap/9-WA-a <RECOpenRains County, Texas: Energy
With Chest Waders, Hip Boots, Or Rain Gear R. O. Parker Jr.
in addition to the boots and rain gear (fig. 1). FEET FIRST When you fall feet first into the water, airWith Chest Waders, Hip Boots, Or Rain Gear R. O. Parker Jr. Neither chest wade rs, hip boots, nor rain ge a r will cause you to drown if you don't panic . Wade rs, the m ost dreaded of the thre e, can
Acid rain control strategists overlook dust removal benefits
Not Available
1989-09-01T23:59:59.000Z
Various strategies for controlling acid rain by reducing SO{sub 2} from existing utilities have failed to take into account the incidental particulate removal abilities of SO{sub 2} scrubbers. This has resulted in over-estimating the costs of acid rain control by 25% or more. This oversight has also caused utilities to invest in preliminary engineering of precipitator upgrades which will never have to be made if scrubbers are installed. While it seems inexplicable that a factor of this importance could have been overlooked by the industry, it is because of the unique situation in old U.S. utility power plants. These plants have relatively inefficient particulate control equipment which is not subject to new source performance standards. New power plants incorporate highly efficient particulate control devices so the ability of the downstream scrubbers to remove dust is irrelevant. The very small amount of particulate entering the scrubber from a highly efficient precipitator could be offset by escaping sulfate particles from a poorly operated scrubber. So an informal guideline was established to indicate that the scrubber had no overall effect on particulate emissions. The industry has generalized upon this guideline when, in fact, it only applies to new plants. The McIlvaine Company in its FGD Knowledge Network has thoroughly documented evidence that SO{sub 2} scrubbers will remove as much as 95% of the particulate being emitted from the relatively low efficiency precipitators operating on the nations existing coal-fired power plants.
A manifestly gauge invariant exact renormalization group
Stefano Arnone; Antonio Gatti; Tim R. Morris
2002-07-16T23:59:59.000Z
A manifestly gauge invariant exact renormalization group for pure SU(N) Yang-Mills theory is proposed, allowing gauge invariant calculations, without any gauge fixing or ghosts. The necessary gauge invariant regularisation which implements the effective cutoff, is naturally incorporated by embedding the theory into a spontaneously broken SU(N|N) super-gauge theory. This guarantees finiteness to all orders in perturbation theory.
A manifestly gauge invariant exact renormalization group
Arnone, S; Morris, T R; Arnone, Stefano; Gatti, Antonio; Morris, Tim R.
2002-01-01T23:59:59.000Z
A manifestly gauge invariant exact renormalization group for pure SU(N) Yang-Mills theory is proposed, allowing gauge invariant calculations, without any gauge fixing or ghosts. The necessary gauge invariant regularisation which implements the effective cutoff, is naturally incorporated by embedding the theory into a spontaneously broken SU(N|N) super-gauge theory. This guarantees finiteness to all orders in perturbation theory.
Long, David G.
signature is altered by rain. Rain striking the water creates splash products including rings, stalksIEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 45, NO. 3, MARCH 2007 621 A C-Band Wind/Rain--With the confirmed evidence of rain surface pertur- bation in recent studies, the rain effects on C
Rain splash of dry sand revealed by high-speed imaging and sticky paper splash targets
Mudd, Simon Marius
Rain splash of dry sand revealed by high-speed imaging and sticky paper splash targets David Jon by raindrop impacts. We use high-speed imaging of drop impacts on dry sand to describe the drop (2007), Rain splash of dry sand revealed by high-speed imaging and sticky paper splash targets, J
Seasonal controls on the exchange of carbon and water in an Amazonian rain forest
Saleska, Scott
Seasonal controls on the exchange of carbon and water in an Amazonian rain forest Lucy R. Hutyra,1 controls on the exchange of carbon and water in an Amazonian rain forest, J. Geophys. Res., 112, G03008 response to climate and weather. This study presents 4 years of eddy covariance data for CO2 and water
(4m x 5m) and can hold vast amounts of water at any given time. The bowl shaped rain garden must is an important parameter since the soil used effects the water absorption ability of the rain garden. The optimalUBC Social Ecological Economic Development Studies (SEEDS) Student Report Water Management through
Daniel, Rosenfeld
The roles of cloud drop effective radius and LWP in determining rain properties in marine that adding cloud condensation nuclei to marine stratocumulus can prevent their breakup from closed into open in terms of cloud drop effective radius (re). Rain is initiated when re near cloud top is around 1214 mm
On the infiltration of rain water through the soil with runo# of the excess water
Fasano, Antonio
On the infiltration of rain water through the soil with runo# of the excess water Iacopo Borsi '' Viale Morgagni 67/A, 50134 Firenze, Italy Abstract This paper deals with the modelling of the rain water infiltration through the soil above the aquifer in case of runo# of the excess water. The main feature
Optical Abelian Lattice Gauge Theories
L. Tagliacozzo; A. Celi; A. Zamora; M. Lewenstein
2013-02-07T23:59:59.000Z
We discuss a general framework for the realization of a family of abelian lattice gauge theories, i.e., link models or gauge magnets, in optical lattices. We analyze the properties of these models that make them suitable to quantum simulations. Within this class, we study in detail the phases of a U(1)-invariant lattice gauge theory in 2+1 dimensions originally proposed by Orland. By using exact diagonalization, we extract the low-energy states for small lattices, up to 4x4. We confirm that the model has two phases, with the confined entangled one characterized by strings wrapping around the whole lattice. We explain how to study larger lattices by using either tensor network techniques or digital quantum simulations with Rydberg atoms loaded in optical lattices where we discuss in detail a protocol for the preparation of the ground state. We also comment on the relation between standard compact U(1) LGT and the model considered.
Energy-momentum conservation laws in gauge theory with broken gauge symmetries
G. Sardanashvily
2002-03-29T23:59:59.000Z
If a Lagrangian of gauge theory of internal symmetries is not gauge-invariant, the energy-momentum fails to be conserved in general.
Additional Rain Sensors within the UBC Irrigation System Michael Thiessen, Chelsie Drysdale University of Installing Additional Rain Sensors within the UBC Irrigation System A Business Case Analysis Prepared for: Dr................................................................................................................................................................... 5 DESCRIPTION OF CURRENT UBC IRRIGATION WATER USE
Runoff water quality of reclaimed mine spoil in the post oak savannah of Texas
Trouart, Joel Elizabeth
1989-01-01T23:59:59.000Z
samples were thawed, filtered and analyzed for nitrite and nitrate using diazotization and cadmium reduction techniques with an autoanalyzer (APHA 1976). Rainfall, temperature, and humidity were continuously monitored using a tipping bucket rain gauge... simulator. banality and quantity of runoff were determined for each plot. Parameters analyzed included: settleable solids, total filterable solids, sediment production, infiltration rate, nitrites, nitrates, total iron and total manganese. The greatest...
, you will be able to easily fill a watering can or use gravity to water your plants. 6. A full rain water collected in these rain barrels for drinking or cooking. Although these are food-grade barrels of dish soap to the rain barrel to stop the mosquitoes from laying eggs in the water. Dish soap
Conformal Gauge Transformations in Thermodynamics
A. Bravetti; C. S. Lopez-Monsalvo; F. Nettel
2015-06-23T23:59:59.000Z
In this work we consider conformal gauge transformations of the geometric structure of thermodynamic fluctuation theory. In particular, we show that the Thermodynamic Phase Space is naturally endowed with a non-integrable connection, defined by all those processes that annihilate the Gibbs 1-form, i.e. reversible processes. Therefore the geometry of reversible processes is invariant under re-scalings, that is, it has a conformal gauge freedom. Interestingly, as a consequence of the non-integrability of the connection, its curvature is not invariant under conformal gauge transformations and, therefore, neither is the associated pseudo-Riemannian geometry. We argue that this is not surprising, since these two objects are associated with irreversible processes. Moreover, we provide the explicit form in which all the elements of the geometric structure of the Thermodynamic Phase Space change under a conformal gauge transformation. As an example, we revisit the change of the thermodynamic representation and consider the resulting change between the two metrics on the Thermodynamic Phase Space which induce Weinhold's energy metric and Ruppeiner's entropy metric. As a by-product we obtain a proof of the well-known conformal relation between Weinhold's and Ruppeiner's metrics along the equilibrium directions. Finally, we find interesting properties of the almost para-contact structure and of its eigenvectors which may be of physical interest.
Renormalization in Coulomb gauge QCD
A. Andrasi; J. C. Taylor
2010-10-28T23:59:59.000Z
In the Coulomb gauge of QCD, the Hamiltonian contains a non-linear Christ-Lee term, which may alternatively be derived from a careful treatment of ambiguous Feynman integrals at 2-loop order. We investigate how and if UV divergences from higher order graphs can be consistently absorbed by renormalization of the Christ-Lee term. We find that they cannot.
Geometrical Methods in Gauge Theory
Henrique de A. Gomes
2006-10-25T23:59:59.000Z
In this work we explore the geometrical interpretation of gauge theories through the formalism of fiber bundles. Moreover, we conduct an investigation in the topology of fiber bundles, providing a proof of the Classification Theorem. In the last chapter we present some applications, such as electromagnetism and generalized Kaluza-Klein Theory.
Note on Discrete Gauge Anomalies
T. Banks; M. Dine
1991-10-02T23:59:59.000Z
We consider the probem of gauging discrete symmetries. All valid constraints on such symmetries can be understood in the low energy theory in terms of instantons. We note that string perturbation theory often exhibits global discrete symmetries, which are broken non-perturbatively.
Gauge Invariance and Fractional Statistics
A. R. P. Lima; R. R. Landim
2006-10-04T23:59:59.000Z
We present a new $(2+1)$-dimensional field theory showing exotic statistics and fractional spin. This theory is achieved through a redefinition of the gauge field $A_{\\mu}$. New properties are found. Another way to implement the field redefinition is used with the same results obtained.
Gauge theories on noncommutative euclidean spaces
Albert Schwarz
2001-11-30T23:59:59.000Z
We consider gauge theories on noncommutative euclidean space . In particular, we discuss the structure of gauge group following standard mathematical definitions and using the ideas of hep-th/0102182.
Frozen ghosts in thermal gauge field theory
P. V. Landshoff; A. Rebhan
2009-03-10T23:59:59.000Z
We review an alternative formulation of gauge field theories at finite temperature where unphysical degrees of freedom of gauge fields and the Faddeev-Popov ghosts are kept at zero temperature.
Ruf, Christopher
IMPROVED MICROWAVE REMOTE SENSING OF HURRICANE WIND SPEED AND RAIN RATES USING THE HURRICANE) that measures wind speed and rain rate along the ground track directly beneath the aircraft. This paper presents are presented, which illustrate wind speed and rain rate measurement spatial resolutions and swath coverage. 1
Multi-step contrast sensitivity gauge
Quintana, Enrico C; Thompson, Kyle R; Moore, David G; Heister, Jack D; Poland, Richard W; Ellegood, John P; Hodges, George K; Prindville, James E
2014-10-14T23:59:59.000Z
An X-ray contrast sensitivity gauge is described herein. The contrast sensitivity gauge comprises a plurality of steps of varying thicknesses. Each step in the gauge includes a plurality of recesses of differing depths, wherein the depths are a function of the thickness of their respective step. An X-ray image of the gauge is analyzed to determine a contrast-to-noise ratio of a detector employed to generate the image.
Gauge Configurations for Lattice QCD from The Gauge Connection
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
The Gauge Connection is an experimental archive for lattice QCD and a repository of gauge configurations made freely available to the community. Contributors to the archive include the Columbia QCDSP collaboration, the MILC collaboration, and others. Configurations are stored in QCD archive format, consisting of an ASCII header which defines various parameters, followed by binary data. NERSC has also provided some utilities and examples that will aid users in handling the data. Users may browse the archive, but are required to register for a password in order to download data. Contents of the archive are organized under four broad headings: Quenched (more than 1200 configurations); Dynamical, Zero Temperature (more than 300 configurations); MILC Improved Staggered Asqtad Lattices (more than 7000 configurations); and Dynamical, Finite Temperature (more than 1200 configurations)
Jasoni, Richard L [DRI; Larsen, Jessica D [DRI; Lyles, Brad F. [DRI; Healey, John M [DRI; Cooper, Clay A [DRI; Hershey, Ronald L [DRI; Lefebre, Karen J [DRI
2013-04-01T23:59:59.000Z
Pahute Mesa is a groundwater recharge area at the Nevada National Security Site. Because underground nuclear testing was conducted at Pahute Mesa, groundwater recharge may transport radionuclides from underground test sites downward to the water table; the amount of groundwater recharge is also an important component of contaminant transport models. To estimate the amount of groundwater recharge at Pahute Mesa, an INFIL3.0 recharge-runoff model is being developed. Two eddy covariance (EC) stations were installed on Pahute Mesa to estimate evapotranspiration (ET) to support the groundwater recharge modeling project. This data report describes the methods that were used to estimate ET and collect meteorological data. Evapotranspiration was estimated for two predominant plant communities on Pahute Mesa; one site was located in a sagebrush plant community, the other site in a pinyon pine/juniper community. Annual ET was estimated to be 310±13.9 mm for the sagebrush site and 347±15.9 mm for the pinyon pine/juniper site (March 26, 2011 to March 26, 2012). Annual precipitation measured with unheated tipping bucket rain gauges was 179 mm at the sagebrush site and 159 mm at the pinyon pine/juniper site. Annual precipitation measured with bulk precipitation gauges was 222 mm at the sagebrush site and 227 mm at the pinyon pine/juniper site (March 21, 2011 to March 28, 2012). A comparison of tipping bucket versus bulk precipitation data showed that total precipitation measured by the tipping bucket rain gauges was 17 to 20 percent lower than the bulk precipitation gauges. These differences were most likely the result of the unheated tipping bucket precipitation gauges not measuring frozen precipitation as accurately as the bulk precipitation gauges. In this one-year study, ET exceeded precipitation at both study sites because estimates of ET included precipitation that fell during the winter of 2010-2011 prior to EC instrumentation and the precipitation gauges started collecting data in March 2011.
Conformal Scaling Gauge Symmetry and Inflationary Universe
Yue-Liang Wu
2004-02-23T23:59:59.000Z
Considering the conformal scaling gauge symmetry as a fundamental symmetry of nature in the presence of gravity, a scalar field is required and used to describe the scale behavior of universe. In order for the scalar field to be a physical field, a gauge field is necessary to be introduced. A gauge invariant potential action is constructed by adopting the scalar field and a real Wilson-like line element of the gauge field. Of particular, the conformal scaling gauge symmetry can be broken down explicitly via fixing gauge to match the Einstein-Hilbert action of gravity. As a nontrivial background field solution of pure gauge has a minimal energy in gauge interactions, the evolution of universe is then dominated at earlier time by the potential energy of background field characterized by a scalar field. Since the background field of pure gauge leads to an exponential potential model of a scalar field, the universe is driven by a power-law inflation with the scale factor $a(t) \\sim t^p$. The power-law index $p$ is determined by a basic gauge fixing parameter $g_F$ via $p = 16\\pi g_F^2[1 + 3/(4\\pi g_F^2) ]$. For the gauge fixing scale being the Planck mass, we are led to a predictive model with $g_F=1$ and $p\\simeq 62$.
Suppression of rice methane emission by sulfate deposition in simulated acid rain
Gauci, Vincent
limitation had been lifted by the simulated acid rain S deposition. Citation: Gauci, V., N. B. Dise, G process and so the duration of paddy inundation and the employment of mid-season field drainage both
Jayamaha, S.E.G. [National Univ. of Singapore (Singapore). Dept. of Mechanical Engineering
1997-05-01T23:59:59.000Z
Singapore experiences a warm and humid climate with abundant rainfall during the entire year. Such conditions are typical of tropical climates where many of today`s metropolitan cities are situated. Rain has been found to affect the thermal performance of building components in two ways, namely, by cooling the surface during rain and thereafter by drying of the absorbed moisture after rain. However, existing software used for predicting the thermal performance of building components do not consider such effects and are therefore inadequate for accurate estimation of the thermal performance of building components in tropical climates. To overcome these limitations, this study was carried out to investigate the simultaneous heat and moisture flow through porous building materials exposed to outdoor conditions such as solar radiation and rain.
Allowance trading activity and state regulatory rulings : evidence from the U.S. Acid Rain Program
Bailey, Elizabeth M.
1996-01-01T23:59:59.000Z
The U.S. Acid Rain Program is one of the first, and by far the most extensive, applications of a market based approach to pollution control. From the beginning, there has been concern whether utilities would participate ...
Allowance trading activity and state regulatory rulings : evidence from the U.S. Acid Rain Program
Bailey, Elizabeth M.
1998-01-01T23:59:59.000Z
The U.S. Acid Rain Program is one of the first, and by far the most extensive, applications of a market based approach to pollution control. From the beginning, there has been concern whether utilities would participate ...
Analysis of TRMM Precipitation Radar Algorithms and Rain over the Tropics and Southeast Texas
Funk, Aaron
2013-12-10T23:59:59.000Z
rates associated with the attenuation-corrected reflectivity. Updates to the 2A23 algorithm for Version 7 (V7) have resulted in an increase (decrease) in the fraction of rain echo classified as convective (stratiform) compared with previous versions...
The multi-thermal and multi-stranded nature of coronal rain
Antolin, P; Pereira, T M D; van der Voort, L Rouppe; Scullion, E
2015-01-01T23:59:59.000Z
In this work, we analyse coordinated observations spanning chromospheric, TR and coronal temperatures at very high resolution which reveal essential characteristics of thermally unstable plasmas. Coronal rain is found to be a highly multi-thermal phenomenon with a high degree of co-spatiality in the multi-wavelength emission. EUV darkening and quasi-periodic intensity variations are found to be strongly correlated to coronal rain showers. Progressive cooling of coronal rain is observed, leading to a height dependence of the emission. A fast-slow two-step catastrophic cooling progression is found, which may reflect the transition to optically thick plasma states. The intermittent and clumpy appearance of coronal rain at coronal heights becomes more continuous and persistent at chromospheric heights just before impact, mainly due to a funnel effect from the observed expansion of the magnetic field. Strong density inhomogeneities on spatial scales of 0.2"-0.5" are found, in which TR to chromospheric temperature ...
Beamfilling correction study for retrieval of oceanic rain from passive microwave observations
Chen, Ruiyue
2004-09-30T23:59:59.000Z
Constant in R-T relationship????????????.??..?.??. 6 2 Spatial resolution for each TMI channel?????????????... 7 3 ARMAR system parameters ?????????.????????... 13 4 The impact of path averaging on STD of rain rate ??????..??? 21 5... Comparison of rain rate STD between TOGA/COARE and KWAJEX ? 30 6 Local BCF uncertainty derived from KWAJEX ARMAR data for TMI?.. 40 7 Same as Table 6 except from TOGA/COARE ARMAR data ????.? 40...
Integrated Title V/acid rain permits: Transitioning through initial permit issuance and reopenings
Bloomfield, C. [Environmental Protection Agency, San Francisco, CA (United States)
1995-12-31T23:59:59.000Z
Titles IV and V of the Clean Air Act Amendments of 1990 (Act or CAA) created two new stationary source permitting programs, one specific to acid rain (Title IV), and a second for operating permits in general (Title V). The Phase 2 portion of the acid rain program was designed to be implemented through the Title V operating permit program, thereby subjecting all Phase 2 acid rain sources to the requirements of Title V. Permits issued pursuant to Phase 2 of the acid rain program will be viewed as a self-contained portion of the Title V operating permit and will be governed by regulations promulgated under both Title IV and Title V. The requirements imposed by Title IV may not always be consistent with the broader operating permit program requirements of Title V, and when inconsistency occurs, the acid rain requirements will take precedence. This nonalignment will perhaps be most apparent during two stages of initial permitting: (1) the transition period following Title V program approval when permit application, issuance, and effective dates differ between the two programs, and (2) at the point when acid rain permits must be reopened to incorporate Phase 2 NO{sub x} requirements. This paper explores strategies for streamlining implementation of the two programs with particular focus on these two coordination issues.
Morphology of rain water channelization in systematically varied model sandy soils
Y. Wei; C. M. Cejas; R. Barrois; R. Dreyfus; D. J. Durian
2014-03-13T23:59:59.000Z
We visualize the formation of fingered flow in dry model sandy soils under different raining conditions using a quasi-2d experimental set-up, and systematically determine the impact of soil grain diameter and surface wetting property on water channelization phenomenon. The model sandy soils we use are random closely-packed glass beads with varied diameters and surface treatments. For hydrophilic sandy soils, our experiments show that rain water infiltrates into a shallow top layer of soil and creates a horizontal water wetting front that grows downward homogeneously until instabilities occur to form fingered flows. For hydrophobic sandy soils, in contrast, we observe that rain water ponds on the top of soil surface until the hydraulic pressure is strong enough to overcome the capillary repellency of soil and create narrow water channels that penetrate the soil packing. Varying the raindrop impinging speed has little influence on water channel formation. However, varying the rain rate causes significant changes in water infiltration depth, water channel width, and water channel separation. At a fixed raining condition, we combine the effects of grain diameter and surface hydrophobicity into a single parameter and determine its influence on water infiltration depth, water channel width, and water channel separation. We also demonstrate the efficiency of several soil water improvement methods that relate to rain water channelization phenomenon, including pre-wetting sandy soils at different level before rainfall, modifying soil surface flatness, and applying superabsorbent hydrogel particles as soil modifiers.
Gauge-invariant signatures of spontaneous gauge symmetry breaking by the Hosotani mechanism
Oscar Akerlund; Philippe de Forcrand
2015-03-02T23:59:59.000Z
The Hosotani mechanism claims to achieve gauge-symmetry breaking, for instance $SU(3) \\to SU(2)\\times U(1)$. To verify this claim, we propose to monitor the stability of a topological defect stable under a gauge subgroup but not under the whole gauge group, like a $U(1)$ flux state or monopole in the case above. We use gauge invariant operators to probe the presence of the topological defect to avoid any ambiguity introduced by gauge fixing. Our method also applies to an ordinary gauge-Higgs system.
Localization principle in SUSY gauge theories
Hosomichi, Kazuo
2015-01-01T23:59:59.000Z
Localization principle is a powerful analytic tool in supersymmetric gauge theories which enables one to perform supersymmetric path integrals explicitly. Many important formulae have been obtained, and they led to a major breakthrough in the understanding of gauge theories at strong coupling as well as the dynamics of branes in M-theory. Some of those results are reviewed, focusing especially on Pestun's solution to four-dimensional N=2 supersymmetric gauge theories on S^4 and the subsequent developments on three or four-dimensional gauge theories on spheres.
SUSY gauge theory on graded manifolds
G. Sardanashvily; W. Wachowski
2014-06-24T23:59:59.000Z
Lagrangian classical field theory of even and odd fields is adequately formulated in terms of fibre bundles and graded manifolds. In particular, conventional Yang-Mills gauge theory is theory of connections on smooth principal bundles, but its BRST extension involves odd ghost fields an antifields on graded manifolds. Here, we formulate Yang-Mills theory of Grassmann-graded gauge fields associated to Lie superalgebras on principal graded bundles. A problem lies in a geometric definition of odd gauge fields. Our goal is Yang--Mills theory of graded gauge fields and its BRST extension.
Towards the Natural Gauge Mediation
Ding, Ran; Wang, Liucheng; Zhu, Bin
2015-01-01T23:59:59.000Z
The sweet spot supersymmetry (SUSY) solves the mu problem in the Minimal Supersymmetric Standard Model (MSSM) with gauge mediated SUSY breaking (GMSB) via the generalized Giudice-Masiero (GM) mechanism where only the mu-term and soft Higgs masses are generated at the unification scale of the Grand Unified Theory (GUT) due to the approximate PQ symmetry. Because all the other SUSY breaking soft terms are generated via the GMSB below the GUT scale, there exists SUSY electroweak (EW) fine-tuning problem to explain the 125 GeV Higgs boson mass due to small trilinear soft term. Thus, to explain the Higgs boson mass, we propose the GMSB with both the generalized GM mechanism and Higgs-messenger interactions. The renormalization group equations are runnings from the GUT scale down to EW scale. So the EW symmetry breaking can be realized easier. We can keep the gauge coupling unification and solution to the flavor problem in the GMSB, as well as solve the \\mu/B_{\\mu}-problem. Moreover, there are only five free parame...
Huang, Changcheng
Abstract-- Rain, snow, gaseous, cloud, fog, scintillation and other atmospheric properties can have, cloud, fog and tropospheric scintillation attenuations affect satellite links at Ku and Ka bands
Gravitational Correction to Running of Gauge Couplings
Sean P. Robinson; Frank Wilczek
2006-06-09T23:59:59.000Z
We calculate the contribution of graviton exchange to the running of gauge couplings at lowest non-trivial order in perturbation theory. Including this contribution in a theory that features coupling constant unification does not upset this unification, but rather shifts the unification scale. When extrapolated formally, the gravitational correction renders all gauge couplings asymptotically free.
Gauge invariant Lagrangian for non-Abelian tensor gauge fields of fourth rank
G. Savvidy; T. Tsukioka
2005-12-31T23:59:59.000Z
Using generalized field strength tensors for non-Abelian tensor gauge fields one can explicitly construct all possible Lorentz invariant quadratic forms for rank-4 non-Abelian tensor gauge fields and demonstrate that there exist only two linear combinations of them which form a gauge invariant Lagrangian. Together with the previous construction of independent gauge invariant forms for rank-2 and rank-3 tensor gauge fields this construction proves the uniqueness of early proposed general Lagrangian up to rank-4 tensor fields. Expression for the coefficients of the general Lagrangian is presented in a compact form.
Thread gauge for tapered threads
Brewster, A.L.
1994-01-11T23:59:59.000Z
The thread gauge permits the user to determine the pitch diameter of tapered threads at the intersection of the pitch cone and the end face of the object being measured. A pair of opposed anvils having lines of threads which match the configuration and taper of the threads on the part being measured are brought into meshing engagement with the threads on opposite sides of the part. The anvils are located linearly into their proper positions by stop fingers on the anvils that are brought into abutting engagement with the end face of the part. This places predetermined reference points of the pitch cone of the thread anvils in registration with corresponding points on the end face of the part being measured, resulting in an accurate determination of the pitch diameter at that location. The thread anvils can be arranged for measuring either internal or external threads. 13 figures.
Phases of chiral gauge theories
Appelquist, Thomas [Department of Physics, Yale University, New Haven, Conneticut 06520-8120 (United States)] [Department of Physics, Yale University, New Haven, Conneticut 06520-8120 (United States); Duan, Zhiyong [Department of Physics, Yale University, New Haven, Conneticut 06520-8120 (United States)] [Department of Physics, Yale University, New Haven, Conneticut 06520-8120 (United States); Sannino, Francesco [Department of Physics, Yale University, New Haven, Conneticut 06520-8120 (United States)] [Department of Physics, Yale University, New Haven, Conneticut 06520-8120 (United States)
2000-06-15T23:59:59.000Z
We discuss the behavior of two non-supersymmetric chiral SU(N) gauge theories, involving fermions in the symmetric and antisymmetric two-index tensor representations respectively. In addition to global anomaly matching, we employ a recently proposed inequality constraint on the number of effective low energy (massless) degrees of freedom of a theory, based on the thermodynamic free energy. Several possible zero temperature phases are consistent with the constraints. A simple picture for the phase structure emerges if these theories choose the phase, consistent with global anomaly matching, that minimizes the massless degree of freedom count defined through the free energy. This idea suggests that confinement with the preservation of the global symmetries through the formation of massless composite fermions is in general not preferred. While our discussion is restricted mainly to bilinear condensate formation, higher dimensional condensates are considered for one case. We conclude by commenting briefly on two related supersymmetric chiral theories. (c) 2000 The American Physical Society.
Gauge Trimming of Neutrino Masses
Chen, Mu-Chun; /Fermilab /UC, Irvine; de Gouvea, Andre; /Northwestern U. /Fermilab; Dobrescu, Bogdan A.; /Fermilab
2006-12-01T23:59:59.000Z
We show that under a new U(1) gauge symmetry, which is non-anomalous in the presence of one ''right-handed neutrino'' per generation and consistent with the standard model Yukawa couplings, the most general fermion charges are determined in terms of four rational parameters. This generalization of the B-L symmetry with generation-dependent lepton charges leads to neutrino masses induced by operators of high dimensionality. Neutrino masses are thus naturally small without invoking physics at energies above the TeV scale, whether neutrinos are Majorana or Dirac fermions. This ''Leptocratic'' Model predicts the existence of light quasi-sterile neutrinos with consequences for cosmology, and implies that collider experiments may reveal the origin of neutrino masses.
Can (Electric-Magnetic) Duality Be Gauged?
Claudio Bunster; Marc Henneaux
2014-03-13T23:59:59.000Z
There exists a formulation of the Maxwell theory in terms of two vector potentials, one electric and one magnetic. The action is then manifestly invariant under electric-magnetic duality transformations, which are rotations in the two-dimensional internal space of the two potentials, and local. We ask the question: can duality be gauged? The only known and battled-tested method of accomplishing the gauging is the Noether procedure. In its decanted form, it amounts to turn on the coupling by deforming the abelian gauge group of the free theory, out of whose curvatures the action is built, into a non-abelian group which becomes the gauge group of the resulting theory. In this article, we show that the method cannot be successfully implemented for electric-magnetic duality. We thus conclude that, unless a radically new idea is introduced, electric-magnetic duality cannot be gauged. The implication of this result for supergravity is briefly discussed.
Towards the Natural Gauge Mediation
Ran Ding; Tianjun Li; Liucheng Wang; Bin Zhu
2015-06-01T23:59:59.000Z
The sweet spot supersymmetry (SUSY) solves the mu problem in the Minimal Supersymmetric Standard Model (MSSM) with gauge mediated SUSY breaking (GMSB) via the generalized Giudice-Masiero (GM) mechanism where only the mu-term and soft Higgs masses are generated at the unification scale of the Grand Unified Theory (GUT) due to the approximate PQ symmetry. Because all the other SUSY breaking soft terms are generated via the GMSB below the GUT scale, there exists SUSY electroweak (EW) fine-tuning problem to explain the 125 GeV Higgs boson mass due to small trilinear soft term. Thus, to explain the Higgs boson mass, we propose the GMSB with both the generalized GM mechanism and Higgs-messenger interactions. The renormalization group equations are runnings from the GUT scale down to EW scale. So the EW symmetry breaking can be realized easier. We can keep the gauge coupling unification and solution to the flavor problem in the GMSB, as well as solve the \\mu/B_{\\mu}-problem. Moreover, there are only five free parameters in our model. So we can determine the characteristic low energy spectra and explore its distinct phenomenology. The low-scale fine-tuning measure can be as low as 20 with the light stop mass below 1 TeV and gluino mass below 2 TeV. The gravitino dark matter can come from a thermal production with the correct relic density and be consistent with the thermal leptogenesis. Because gluino and stop can be relatively light in our model, how to search for such GMSB at the upcoming run II of the LHC experiment could be very interesting.
Unifying Geometrical Representations of Gauge Theory
Scott T Alsid; Mario A Serna
2014-10-28T23:59:59.000Z
We unify three approaches within the vast body of gauge-theory research that have independently developed distinct representations of a geometrical surface-like structure underlying the vector-potential. The three approaches that we unify are: those who use the compactified dimensions of Kaluza-Klein theory, those who use Grassmannian models (also called gauge theory embedding or $CP^{N-1}$ models) to represent gauge fields, and those who use a hidden spatial metric to replace the gauge fields. In this paper we identify a correspondence between the geometrical representations of the three schools.Each school was mostly independently developed, does not compete with other schools, and attempts to isolate the gauge-invariant geometrical surface-like structures that are responsible for the resulting physics. By providing a mapping between geometrical representations, we hope physicists can now isolate representation-dependent physics from gauge-invariant physical results and share results between each school. We provide visual examples of the geometrical relationships between each school for $U(1)$ electric and magnetic fields. We highlight a first new result: in all three representations a static electric field (electric field from a fixed ring of charge or a sphere of charge) has a hidden gauge-invariant time dependent surface that is underlying the vector potential.
Jiang, Haiyan
and freshwater flooding is the number one cause of death from hurricanes in the United States (Elsberry 2002 1998Â2000, Lonfat et al. (2004) showed that the maximum azimuthally averaged rainfall rate is about 12. of rain (24 h) 1 ] and Tropical Storm Allison (2001, $6 billion in damages, 27 deaths, 35Â40 in. of rain
The effective action in Coulomb gauge QCD
A. Andrasi; J. C. Taylor
2015-03-29T23:59:59.000Z
At 2-loop order, Feynman integrals in the Coulomb gauge are divergent over the internal energy variables. Nevertheless, it is known how to calculate the effective action provided that the external gluon fields are all transverse. We show that, for the two-gluon Greens function as an example, the method can be extended to include longitudinal external fields. The longitudinal Greens functions appear in the BRST identities. As an intermediate step, we use a flow gauge, which interpolates between the Feynman and Coulomb gauges.
Ruf, Christopher
HURRICANE IMAGING RADIOMETER WIND SPEED AND RAIN RATE RETRIEVAL: [PART-1] DEVELOPMENT U.S.A * selnimri@mail.ucf.edu 2 NOAA/AOML/Hurricane Research Division, Miami, Florida, USA 3 Space model has been developed to support the analysis and design of the new airborne Hurricane Imaging
Formation and evolution of coronal rain observed by SDO/AIA on February 22, 2012
Vashalomidze, Z; Zaqarashvili, T V; Oliver, R; Shergelashvili, B; Ramishvili, G; Poedts, S; De Causmaecker, P
2015-01-01T23:59:59.000Z
The formation and dynamics of coronal rain are currently not fully understood. Coronal rain is the fall of cool and dense blobs formed by thermal instability in the solar corona towards the solar surface with acceleration smaller than gravitational free fall. We aim to study the observational evidence of the formation of coronal rain and to trace the detailed dynamics of individual blobs. We used time series of the 171 \\AA\\, and 304 \\AA\\, spectral lines obtained by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO) above active region AR 11420 on February 22, 2012. Observations show that a coronal loop disappeared in the 171 \\AA\\ channel and appeared in the 304 \\AA\\ line$\\text{}\\text{}$ more than one hour later, which indicates a rapid cooling of the coronal loop from 1 MK to 0.05 MK. An energy estimation shows that the radiation is higher than the heat input, which indicates so-called catastrophic cooling. The cooling was accompanied by the formation of coronal rain in the fo...
A phase screen model for simulating numerically the propagation of a laser beam in rain
Lukin, I P; Rychkov, D S; Falits, A V [Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Tomsk (Russian Federation); Lai, Kin S; Liu, Min R [DSO National Laboratories 20 (Singapore)
2009-09-30T23:59:59.000Z
The method based on the generalisation of the phase screen method for a continuous random medium is proposed for simulating numerically the propagation of laser radiation in a turbulent atmosphere with precipitation. In the phase screen model for a discrete component of a heterogeneous 'air-rain droplet' medium, the amplitude screen describing the scattering of an optical field by discrete particles of the medium is replaced by an equivalent phase screen with a spectrum of the correlation function of the effective dielectric constant fluctuations that is similar to the spectrum of a discrete scattering component - water droplets in air. The 'turbulent' phase screen is constructed on the basis of the Kolmogorov model, while the 'rain' screen model utiises the exponential distribution of the number of rain drops with respect to their radii as a function of the rain intensity. Theresults of the numerical simulation are compared with the known theoretical estimates for a large-scale discrete scattering medium. (propagation of laser radiation in matter)
Gannon, Michael R.
in the Tabonuco Rain Forest of Puerto Rico © Michael R. Gannon 1991 Doctoral would like to convey special thanks to Dr. Waide for support while in Puerto Rico, without which expertise and logistic support in Puerto Rico, and to Stephen B. Cox for assisting with computer data entry
Adaptive FIR Filtering of Range Sidelobes for Air and Spaceborne Rain Mapping Stephen P. Lohmeier
Kansas, University of
Adaptive FIR Filtering of Range Sidelobes for Air and Spaceborne Rain Mapping Stephen P. Lohmeier and Telecommunications Center Abstract This paper describes an adaptive finite-impulse response (FIR) filteringB [1] sidelobe levels. Although others have used wavelets to achieve suppression [2]. To measure light
Midweek increase in U.S. summer rain and storm heights suggests air pollution
Daniel, Rosenfeld
Midweek increase in U.S. summer rain and storm heights suggests air pollution invigorates air pollution suppresses cloud-drop coalescence and early rainout during the growth of thunderstorms suggests air pollution invigorates rainstorms, J. Geophys. Res., 113, D02209, doi:10.1029/2007JD008623. 1
RADARSAT SCANSAR WIND RETRIEVAL AND RAIN EFFECTS ON SCANSAR MEASUREMENTS UNDER HURRICANE CONDITIONS
Long, David G.
RADARSAT SCANSAR WIND RETRIEVAL AND RAIN EFFECTS ON SCANSAR MEASUREMENTS UNDER HURRICANE CONDITIONS CB, Provo, Utah 84602 ABSTRACT RADARSAT-1 ScanSAR SWA images of Hurricane Katrina are used-band polarization ratio models have been proposed, none have been well verified in hurricane conditions. Although C
Network Coded Information Raining over High-Speed Rail through IEEE 802.16j
Valaee, Shahrokh
Network Coded Information Raining over High-Speed Rail through IEEE 802.16j Christopher Sue, Sameh propose a two-hop wireless network architecture for high-speed rail employing 802.16j. Due to its backward in high-speed rail communications and better exploit relay diversity. We refer to our proposed scheme
Stephens, Graeme L.
it one of the most innovative citizen science programs in the nation. Students of all ages at over 100Crowdsourcing, Climate Change and Student Science: The Community Collaborative Rain, Hail and Snow: Dr. Nolan Doesken Address: Department of Atmospheric Science 1371 Campus Delivery Colorado State
Rain Forest Islands in the Chilean Semiarid Region: Fog-dependency,
Rain Forest Islands in the Chilean Semiarid Region: Fog-dependency, Ecosystem Persistence and Tree that these forests persist as a result of fog-water inputs. If so, then because fog-water deposition is spatially by the direction of fog input should determine forest structure and tree regeneration patterns. To investigate
Exceptional Collections and del Pezzo Gauge Theories
Christopher P. Herzog
2004-02-16T23:59:59.000Z
Stacks of D3-branes placed at the tip of a cone over a del Pezzo surface provide a way of geometrically engineering a small but rich class of gauge/gravity dualities. We develop tools for understanding the resulting quiver gauge theories using exceptional collections. We prove two important results for a general quiver gauge theory: 1) we show the ordering of the nodes can be determined up to cyclic permutation and 2) we derive a simple formula for the ranks of the gauge groups (at the conformal point) in terms of the numbers of bifundamentals. We also provide a detailed analysis of four node quivers, examining when precisely mutations of the exceptional collection are related to Seiberg duality.
Translational-invariant noncommutative gauge theory
F. Ardalan; N. Sadooghi
2010-11-18T23:59:59.000Z
A generalized translational invariant noncommutative field theory is analyzed in detail, and a complete description of translational invariant noncommutative structures is worked out. The relevant gauge theory is described, and the planar and nonplanar axial anomalies are obtained.
Translational-invariant noncommutative gauge theory
Ardalan, F. [Department of Physics, Sharif University of Technology, P.O. Box 11155-9161, Tehran (Iran, Islamic Republic of); Institute for Studies in Theoretical Physics and Mathematics (IPM), School of Physics, P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Sadooghi, N. [Department of Physics, Sharif University of Technology, P.O. Box 11155-9161, Tehran (Iran, Islamic Republic of)
2011-01-15T23:59:59.000Z
A generalized translational-invariant noncommutative field theory is analyzed in detail, and a complete description of translational-invariant noncommutative structures is worked out. The relevant gauge theory is described, and the planar and nonplanar axial anomalies are obtained.
Gauge invariant regularisation in the ERG approach
S. Arnone; Yu. A. Kubyshin; T. R. Morris; J. F. Tighe
2001-02-02T23:59:59.000Z
A gauge invariant regularisation which can be used for non-perturbative treatment of Yang-Mills theories within the exact renormalization group approach is constructed. It consists of a spontaneously broken SU(N|N) super-gauge extension of the initial Yang-Mills action supplied with covariant higher derivatives. We demonstrate that the extended theory in four dimensions is ultra-violet finite perturbatively and argue that it has a sensible limit when the regularisation cutoff is removed.
A gauge invariant regulator for the ERG
S. Arnone; Yu. A. Kubyshin; T. R. Morris; J. F. Tighe
2001-02-09T23:59:59.000Z
A gauge invariant regularisation for dealing with pure Yang-Mills theories within the exact renormalization group approach is proposed. It is based on the regularisation via covariant higher derivatives and includes auxiliary Pauli-Villars fields which amounts to a spontaneously broken SU(N|N) super-gauge theory. We demonstrate perturbatively that the extended theory is ultra-violet finite in four dimensions and argue that it has a sensible limit when the regularization cutoff is removed.
Quantum communication, reference frames and gauge theory
S. J. van Enk
2006-04-26T23:59:59.000Z
We consider quantum communication in the case that the communicating parties not only do not share a reference frame but use imperfect quantum communication channels, in that each channel applies some fixed but unknown unitary rotation to each qubit. We discuss similarities and differences between reference frames within that quantum communication model and gauge fields in gauge theory. We generalize the concept of refbits and analyze various quantum communication protocols within the communication model.
Holographic realization of gauge mediated supersymmetry breaking
Kostas Skenderis; Marika Taylor
2012-09-10T23:59:59.000Z
The general gauge mediation scenario provides a framework in which properties of a visible sector with soft supersymmetry breaking are computed from current correlation functions in the supersymmetry breaking hidden sector. In this paper we will use holography to model strongly coupled hidden sectors by weakly curved geometries and describe how the current correlators relevant for general gauge mediation are computed by holographic methods. We illustrate the general setup by a toy example which captures most of the relevant features.
Trace anomaly of the conformal gauge field
Sladkowski, J
1993-01-01T23:59:59.000Z
The proposed by Bastianelli and van Nieuwenhuizen new method of calculations of trace anomalies is applied in the conformal gauge field case. The result is then reproduced by the heat equation method. An error in previous calculation is corrected. It is pointed out that the introducing gauge symmetries into a given system by a field-enlarging transformation can result in unexpected quantum effects even for trivial configurations.
Noncommutative Gauge Theory with Covariant Star Product
Zet, G. [Physics Department, 'Gh. Asachi' Technical University, 700050 Iasi (Romania)
2010-08-04T23:59:59.000Z
We present a noncommutative gauge theory with covariant star product on a space-time with torsion. In order to obtain the covariant star product one imposes some restrictions on the connection of the space-time. Then, a noncommutative gauge theory is developed applying this product to the case of differential forms. Some comments on the advantages of using a space-time with torsion to describe the gravitational field are also given.
Chaotic thermalization in classical gauge theories
Woitek, Marcio; Krein, Gastao [Instituto de Fisica Teorica, Universidade Estadual Paulista Rua Dr. Bento Teobaldo Ferraz, 271 - Bloco II, Sao Paulo, SP (Brazil)
2013-05-06T23:59:59.000Z
We explore the idea that chaos concepts might be useful for understanding the thermalization in gauge theories. The SU(2) Higgs model is discussed as a prototype of system with gauge fields coupled to matter fields. Through the numerical solution of the equations of motion, we are able to characterize chaotic behavior via the corresponding Lyapunov exponent. Then it is demonstrated that the system's approach to equilibrium can be understood through direct application of the principles of Statistical Mechanics.
Electric-Magnetic Dualities in Gauge Theories
Jun-Kai Ho; Chen-Te Ma
2015-07-28T23:59:59.000Z
Electric-magnetic dualities are equivalence between strong and weak coupling constants. A standard way is to exchange electric and magnetic fields in the abelian gauge theory. We use three ways to perform electric-magnetic dualities in the case of the non-commutative $U(1)$ gauge theory. The first way is to use covariant field strengths to be the electric and magnetic fields. We find an invariant form of the equation of motion after performing the electric-magnetic duality. The second way is to use the Seiberg-Witten map to rewrite the non-commutative $U(1)$ gauge theory in terms of abelian field strength. The third way is that we use the large Neveu Schwarz-Neveu Schwarz (NS-NS) background limit (non-commutativity parameter only has one degree of freedom) to consider the non-commutative $U(1)$ gauge theory or D3-brane. In this limit, we introduce or dualize a new one-form gauge potential to get a D3-brane in a large Ramond-Ramond (R-R) background via field redefinition. We also use perturbation to study equivalence between two D3-brane theories. Comparison on three methods in the non-commutative $U(1)$ gauge theory gives different physical implications. This comparison reflects differences between the non-abelian and non-commutative gauge theories in the electric-magnetic dualities. For a complete study, we also extend our studies to the simplest abelian and non-abelian $p$-form gauge theories, and a non-commutative theory with the non-abelian structure.
Atmospheric deposition of {sup 7}Be by rain events, incentral Argentina
Ayub, J. Juri; Velasco, H.; Rizzotto, M. [Grupo de Estudios Ambientales. Instituto de Matematica Aplicada San Luis. Universidad National de San Luis--CONICET. Ejercito de los Andes 950. Argentina (Argentina); Di Gregorio, D. E.; Huck, H. [Departamento de Fisica, Comision National de Energia Atomica, Av. Gral. Paz 1499, 1650 San Martin, Provincia de Buenos Aires (Argentina); Escuela de Ciencia y Tecnologia, Universidad National de San Martin. Martin de Irigoyen 3100, 1650 San Martin, Provincia de Buenos Aires, Argentina. (Argentina)
2008-08-07T23:59:59.000Z
Beryllium-7 is a natural radionuclide that enters into the ecosystems through wet and dry depositions and has numerous environmental applications in terrestrial and aquatic ecosystems. Atmospheric wet deposition of {sup 7}Be was measured in central Argentina. Rain traps were installed (1 m above ground) and individual rain events have been collected. Rain samples were filtered and analyzed by gamma spectrometry. The gamma counting was undertaken using a 40%-efficient p-type coaxial intrinsic high-purity natural germanium crystal built by Princeton Gamma-Tech. The cryostat was made from electroformed high-purity copper using ultralow-background technology. The detector was surrounded by 50 cm of lead bricks to provide shielding against radioactive background. The detector gamma efficiency was determined using a water solution with known amounts of chemical compounds containing long-lived naturally occurring radioisotopes, {sup 176}Lu, {sup 138}La and {sup 40}K. Due to the geometry of the sample and its position close to the detector, the efficiency points from the {sup 176}Lu decay, had to be corrected for summing effects. The measured samples were 400 ml in size and were counted curing one day. The {sup 7}Be detection limit for the present measurements was as low as 0.2 Bq l{sup -1}. Thirty two rain events were sampled and analyzed (November 2006-May 2007). The measured values show that the events corresponding to low rainfall (<20 mm) are characterized by significantly higher activity concentrations (Bq l{sup -1}). The activity concentration of each individual event varied from 0.8 to 3.5 Bq l{sup -1}, while precipitations varied between 4 and 70 mm. The integrated activity by event of {sup 7}Be was fitted with a model that takes into account the precipitation amount and the elapsed time between two rain events. The integrated activities calculated with this model show a good agreement with experimental values.
Derivative expansion and gauge independence of the false vacuum decay rate in various gauges
D. Metaxas
2001-01-08T23:59:59.000Z
In theories with radiative symmetry breaking, the calculation of the false vacuum decay rate requires the inclusion of higher-order terms in the derivative expansion of the effective action. I show here that, in the case of covariant gauges, the presence of infrared singularities forbids the consistent calculation by keeping the lowest-order terms. The situation is remedied, however, in the case of $R_{\\xi}$ gauges. Using the Nielsen identities I show that the final result is gauge independent for generic values of the gauge parameter $v$ that are not anomalously small.
A Higgs Boson Composed of Gauge Bosons F. J. Himpsel
Himpsel, Franz J.
A Higgs Boson Composed of Gauge Bosons F. J. Himpsel Department of Physics, University of Wisconsin to replace the Higgs boson of the standard model by a Lorentz- and gauge- invariant combination of SU(2) gauge bosons. A pair of Higgs bosons is identified with pairs of gauge bosons by setting their mass
Closed string field theory in a-gauge
Masako Asano; Mitsuhiro Kato
2012-09-09T23:59:59.000Z
We show that a-gauge, a class of covariant gauges developed for bosonic open string field theory, is consistently applied to the closed string field theory. A covariantly gauge-fixed action of massless fields can be systematically derived from a-gauge-fixed action of string field theory.
Electronic-type vacuum gauges with replaceable elements
Edwards, D. Jr.
1984-09-18T23:59:59.000Z
In electronic devices for measuring pressures in vacuum systems, the metal elements which undergo thermal deterioration are made readily replaceable by making them parts of a simple plug-in unit. Thus, in ionization gauges, the filament and grid or electron collector are mounted on the novel plug-in unit. In thermocouple pressure gauges, the heater and attached thermocouple are mounted on the plug-in unit. Plug-in units have been designed to function, alternatively, as ionization gauge and as thermocouple gauge, thus providing new gauges capable of measuring broader pressure ranges than is possible with either an ionization gauge or a thermocouple gauge. 5 figs.
Lovejoy, Shaun
WATER RESOURCES RESEARCH, VOL. 25, NO. 3, PAGES 577-579, MARCH 1989 Comment on "Are Rain Rate the properties of the rain field with those of its fluctu- ations in such a way that neither of their theorems are rele- vant to the problem of stochasticself-similar rain modeling. We would thereforelike to take
Electric-Magnetic Dualities in Gauge Theories
Ho, Jun-Kai
2015-01-01T23:59:59.000Z
Electric-magnetic dualities are equivalence between strong and weak coupling constants. A standard way is to exchange electric and magnetic fields in the abelian gauge theory. We use three ways to perform electric-magnetic dualities in the case of the non-commutative $U(1)$ gauge theory. The first way is to use covariant field strengths to be the electric and magnetic fields. We find an invariant form of the equation of motion after performing the electric-magnetic duality. The second way is to use the Seiberg-Witten map to rewrite the non-commutative $U(1)$ gauge theory in terms of abelian field strength. The third way is that we use the large Neveu Schwarz-Neveu Schwarz (NS-NS) background limit (non-commutativity parameter only has one degree of freedom) to consider the non-commutative $U(1)$ gauge theory or D3-brane. In this limit, we introduce or dualize a new one-form gauge potential to get a D3-brane in a large Ramond-Ramond (R-R) background via field redefinition. We also use perturbation to study equi...
Primordial anisotropies in gauged hybrid inflation
Abolhasani, Ali Akbar; Emami, Razieh [School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Firouzjahi, Hassan, E-mail: abolhasani@ipm.ir, E-mail: emami@ipm.ir, E-mail: firouzh@mail.lns.cornell.edu [School of Astronomy, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of)
2014-05-01T23:59:59.000Z
We study primordial anisotropies generated in the model of gauged hybrid inflation in which the complex waterfall field is charged under a U(1)gauge field. Primordial anisotropies are generated either actively during inflation or from inhomogeneities modulating the surface of end of inflation during waterfall transition. We present a consistent ?N mechanism to calculate the anisotropic power spectrum and bispectrum. We show that the primordial anisotropies generated at the surface of end of inflation do not depend on the number of e-folds and therefore do not produce dangerously large anisotropies associated with the IR modes. Furthermore, one can find the parameter space that the anisotropies generated from the surface of end of inflation cancel the anisotropies generated during inflation, therefore relaxing the constrains on model parameters imposed from IR anisotropies. We also show that the gauge field fluctuations induce a red-tilted power spectrum so the averaged power spectrum from the gauge field can change the total power spectrum from blue to red. Therefore, hybrid inflation, once gauged under a U(1) field, can be consistent with the cosmological observations.
Coronal rain in magnetic arcades: Rebound shocks, Limit cycles, and Shear flows
Fang, X; Keppens, R; Van Doorsselaere, T
2015-01-01T23:59:59.000Z
We extend our earlier multidimensional, magnetohydrodynamic simulations of coronal rain occurring in magnetic arcades with higher resolution, grid-adaptive computations covering a much longer ($>6$ hour) timespan. We quantify how in-situ forming blob-like condensations grow along and across field lines and show that rain showers can occur in limit cycles, here demonstrated for the first time in 2.5D setups. We discuss dynamical, multi-dimensional aspects of the rebound shocks generated by the siphon inflows and quantify the thermodynamics of a prominence-corona-transition-region like structure surrounding the blobs. We point out the correlation between condensation rates and the cross-sectional size of loop systems where catastrophic cooling takes place. We also study the variations of the typical number density, kinetic energy and temperature while blobs descend, impact and sink into the transition region. In addition, we explain the mechanisms leading to concurrent upflows while the blobs descend. As a resu...
Gauge Orbit Types for Generalized Connections
Christian Fleischhack
2000-01-05T23:59:59.000Z
Different versions for defining Ashtekar's generalized connections are investigated depending on the chosen smoothness category for the paths and graphs -- the label set for the projective limit. Our definition covers the analytic case as well as the case of webs. Then the orbit types of the generalized connections are determined for compact structure groups. The stabilizer of a connection is homeomorphic to the holonomy centralizer, i.e. the centralizer of its holonomy group, and the homeomorphism class of the gauge orbit is completely determined by the holonomy centralizer. Furthermore, the stabilizers of two connections are conjugate in the gauge group if and only if their holonomy centralizers are conjugate in the structure group. Finally, the gauge orbit type of a connection is defined to be the conjugacy class of its holonomy centralizer equivalently to the standard definition via stabilizers.
The red rain phenomenon of Kerala and its possible extraterrestrial origin
Godfrey Louis; A. Santhosh Kumar
2006-01-02T23:59:59.000Z
A red rain phenomenon occurred in Kerala, India starting from 25th July 2001, in which the rainwater appeared coloured in various localized places that are spread over a few hundred kilometers in Kerala. Maximum cases were reported during the first 10 days and isolated cases were found to occur for about 2 months. The striking red colouration of the rainwater was found to be due to the suspension of microscopic red particles having the appearance of biological cells. These particles have no similarity with usual desert dust. An estimated minimum quantity of 50,000 kg of red particles has fallen from the sky through red rain. An analysis of this strange phenomenon further shows that the conventional atmospheric transport processes like dust storms etc. cannot explain this phenomenon. The electron microscopic study of the red particles shows fine cell structure indicating their biological cell like nature. EDAX analysis shows that the major elements present in these cell like particles are carbon and oxygen. Strangely, a test for DNA using Ethidium Bromide dye fluorescence technique indicates absence of DNA in these cells. In the context of a suspected link between a meteor airburst event and the red rain, the possibility for the extraterrestrial origin of these particles from cometary fragments is discussed.
Rain water transport and storage in a model sandy soil with hydrogel particle additives
Y. Wei; D. J. Durian
2014-02-10T23:59:59.000Z
We study rain water infiltration and drainage in a dry model sandy soil with superabsorbent hydrogel particle additives by measuring the mass of retained water for non-ponding rainfall using a self-built 3D laboratory set-up. In the pure model sandy soil, the retained water curve measurements indicate that instead of a stable horizontal wetting front that grows downward uniformly, a narrow fingered flow forms under the top layer of water-saturated soil. This rain water channelization phenomenon not only further reduces the available rain water in the plant root zone, but also affects the efficiency of soil additives, such as superabsorbent hydrogel particles. Our studies show that the shape of the retained water curve for a soil packing with hydrogel particle additives strongly depends on the location and the concentration of the hydrogel particles in the model sandy soil. By carefully choosing the particle size and distribution methods, we may use the swollen hydrogel particles to modify the soil pore structure, to clog or extend the water channels in sandy soils, or to build water reservoirs in the plant root zone.
Rosenfeld, Daniel; Wang, Hailong; Rasch, Philip J.
2012-07-04T23:59:59.000Z
Numerical simulations described in previous studies showed that adding cloud condensation nuclei to marine stratocumulus can prevent their breakup from closed into open cells. Additional analyses of the same simulations show that the suppression of rain is well described in terms of cloud drop effective radius (re). Rain is initiated when re near cloud top is around 12-14 um. Cloud water starts to get depleted when column-maximum rain intensity (Rmax) exceeds 0.1 mm h-1. This happens when cloud-top re reaches 14 um. Rmax is mostly less than 0.1 mm h-1 at re<14 um, regardless of the cloud water path, but increases rapidly when re exceeds 14 um. This is in agreement with recent aircraft observations and theoretical observations in convective clouds so that the mechanism is not limited to describing marine stratocumulus. These results support the hypothesis that the onset of significant precipitation is determined by the number of nucleated cloud drops and the height (H) above cloud base within the cloud that is required for cloud drops to reach re of 14 um. In turn, this can explain the conditions for initiation of significant drizzle and opening of closed cells providing the basis for a simple parameterization for GCMs that unifies the representation of both precipitating and non-precipitating clouds as well as the transition between them. Furthermore, satellite global observations of cloud depth (from base to top), and cloud top re can be used to derive and validate this parameterization.
Montero, Juan Pablo
The U.S. acid rain program, Title IV of the 1990 Clean Air Act Amendments, is a pioneering experience in environmental regulation by setting a market for electric utility emissions of sulfur dioxide (SO2) and by including ...
Solution of the Gribov problem from gauge invariance
Kurt Langfeld; Tom Heinzl; Anton Ilderton; Martin Lavelle; David McMullan
2008-12-12T23:59:59.000Z
A new approach to gauge fixed Yang-Mills theory is derived using the Polyakov-Susskind projection techniques to build gauge invariant states. In our approach, in contrast to the Faddeev-Popov method, the Gribov problem does not prevent the gauge group from being factored out of the partition function. Lattice gauge theory is used to illustrate the method via a calculation of the static quark-antiquark potential generated by the gauge fields in the fundamental modular region of Coulomb gauge.
Emergent noncommutative gravity from a consistent deformation of gauge theory
Cortese, Ignacio; Garcia, J Antonio [Departamento de Fisica de Altas Energias, Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, Mexico D. F. 04510 (Mexico)
2010-05-15T23:59:59.000Z
Starting from a standard noncommutative gauge theory and using the Seiberg-Witten map, we propose a new version of a noncommutative gravity. We use consistent deformation theory starting from a free gauge action and gauging a killing symmetry of the background metric to construct a deformation of the gauge theory that we can relate with gravity. The result of this consistent deformation of the gauge theory is nonpolynomial in A{sub {mu}.} From here we can construct a version of noncommutative gravity that is simpler than previous attempts. Our proposal is consistent and is not plagued with the problems of other approaches like twist symmetries or gauging other groups.
Gauge mediated supersymmetry breaking and moduli stabilization
Alwis, S. P. de [Physics Department, University of Colorado, Boulder, Colorado 80309 (United States)
2007-10-15T23:59:59.000Z
A generic lesson of string theory is that the coupling constants of an effective low energy theory are determined by the vacuum values of a set of fields - the so-called moduli - some of which are stabilized at relatively low masses by nonperturbative effects. We argue that the physics of these moduli cannot be separated from the issues of dynamical and gauge mediated supersymmetry breaking. To illustrate this point we present a modified version of the type IIB Kachru-Kallosh-Linde-Trivedi model where the criteria for gauge mediated supersymmetry breaking may be realized.
Feynman rules for Coulomb gauge QCD
A. Andrasi; J. C. Taylor
2012-05-29T23:59:59.000Z
The Coulomb gauge in nonabelian gauge theories is attractive in principle, but beset with technical difficulties in perturbation theory. In addition to ordinary Feynman integrals, there are, at 2-loop order, Christ-Lee (CL) terms, derived either by correctly ordering the operators in the Hamiltonian, or by resolving ambiguous Feynman integrals. Renormalization theory depends on the subgraph structure of ordinary Feynamn graphs. The CL terms do not have subgraph structure. We show how to carry out enormalization in the presene of CL terms, by re-expressing these as `pseudo-Feynman' inegrals. We also explain how energy divergences cancel.
Gauge Theories in Noncommutative Homogeneous Kähler Manifolds
Yoshiaki Maeda; Akifumi Sako; Toshiya Suzuki; Hiroshi Umetsu
2014-09-07T23:59:59.000Z
We construct a gauge theory on a noncommutative homogeneous K\\"ahler manifold, where we employ the deformation quantization with separation of variables for K\\"ahler manifolds formulated by Karabegov. A key point in this construction is to obtaining vector fields which act as inner derivations for the deformation quantization. We show that these vector fields are the only Killing vector fields. We give an explicit construction of this gauge theory on noncommutative ${\\mathbb C}P^N$ and noncommutative ${\\mathbb C}H^N$.
SU(4) pure-gauge string tensions
Shigemi Ohta; Matthew Wingate
1998-08-19T23:59:59.000Z
In response to recently renewed interests in SU(N) pure-gauge dynamics with large N, both from M/string duality and from finite-temperature QCD phase structure, we calculate string tensions acting between the fundamental 4, diquark 6 and other color charges in SU(4) pure-gauge theory at temperatures below the deconfining phase change and above the bulk phase transition. Our results suggest 4 and 6 representations have different string tensions, with a ratio of about 1.3. We also found the deconfining phase change is not strong.
Diffractive Scattering and Gauge/String Duality
Tan, Chung-I [Brown University, Providence, Rhode Island, United States
2009-09-01T23:59:59.000Z
High-energy diffractive scattering will be discussed based on Gauge/String duality. As shown by Brower, Polchinski, Strassler and Tan, the ubiquitous Pomeron emerges naturally in gauge theories with string-theoretical descriptions. Its existence is intimately tied to gluons, and also to the energy-momentum tensor. With a confining dual background metric, the Pomeron can be interpreted as a 'massive graviton'. In a single unified step, both its infrared and ultraviolet properties are dealt with, reflecting confinement and conformal symmetry respectively. An effective field theory for high-energy scattering can be constructed. Applications based on this approach will also be described.
Dyonic Instantons in Five Dimensional Gauge Theories
Neil. D. Lambert; David Tong
1999-07-13T23:59:59.000Z
We show that there exist finite energy, non-singular instanton solutions for five-dimensional theories with broken gauge symmetry. The soliton is supported against collapse by a non-zero electric charge. The low-energy dynamics of these solutions is described by motion on the ADHM moduli space with potential.
Fourier Accelerated Conjugate Gradient Lattice Gauge Fixing
R. J. Hudspith
2014-05-22T23:59:59.000Z
We provide details of the first implementation of a non-linear conjugate gradient method for Landau and Coulomb gauge fixing with Fourier acceleration. We find clear improvement over the Fourier accelerated steepest descent method, with the average time taken for the algorithm to converge to a fixed, high accuracy, being reduced by a factor of 2 to 4.
National Computational Infrastructure for Lattice Gauge Theory
Brower, Richard C.
2014-04-15T23:59:59.000Z
SciDAC-2 Project The Secret Life of Quarks: National Computational Infrastructure for Lattice Gauge Theory, from March 15, 2011 through March 14, 2012. The objective of this project is to construct the software needed to study quantum chromodynamics (QCD), the theory of the strong interactions of sub-atomic physics, and other strongly coupled gauge field theories anticipated to be of importance in the energy regime made accessible by the Large Hadron Collider (LHC). It builds upon the successful efforts of the SciDAC-1 project National Computational Infrastructure for Lattice Gauge Theory, in which a QCD Applications Programming Interface (QCD API) was developed that enables lattice gauge theorists to make effective use of a wide variety of massively parallel computers. This project serves the entire USQCD Collaboration, which consists of nearly all the high energy and nuclear physicists in the United States engaged in the numerical study of QCD and related strongly interacting quantum field theories. All software developed in it is publicly available, and can be downloaded from a link on the USQCD Collaboration web site, or directly from the github repositories with entrance linke http://usqcd-software.github.io
Noncommutative gauge theories and Lorentz symmetry
Banerjee, Rabin; Chakraborty, Biswajit; Kumar, Kuldeep [S.N. Bose National Centre for Basic Sciences, JD Block, Sector 3, Salt Lake, Kolkata 700098 (India)
2004-12-15T23:59:59.000Z
We explicitly derive, following a Noether-like approach, the criteria for preserving Poincare invariance in noncommutative gauge theories. Using these criteria we discuss the various spacetime symmetries in such theories. It is shown that, interpreted appropriately, Poincare invariance holds. The analysis is performed in both the commutative as well as noncommutative descriptions and a compatibility between the two is also established.
Mir Hameeda
2012-05-23T23:59:59.000Z
In this paper we will analyze the quantization of a gauge theory on a four sphere. This will be done by mode expanding all the fields in the theory in terms of harmonic modes. We will also analyse the BRST symmetry of this theory.
Manifest Verification of QCD Gauge Theory
Yu Kun Qian
2008-10-29T23:59:59.000Z
We analyze the magnetic moment of gluon, find if QCD is nongauge SU(3) theory then the magnetic moment of gluon varnishes, but if QCD is gauge theory then the magnetic moment of gluon will not vanishes. The magnetic moment of gluon can be measured by investigate the E-M decay of gluball.
From Lattice Gauge Theories to Hydrogen Atoms
Manu Mathur; T. P. Sreeraj
2014-10-13T23:59:59.000Z
Using canonical transformations we obtain a complete and most economical realization of the loop or physical Hilbert space of pure $SU(2)_{2+1}$ lattice gauge theory in terms of Wigner coupled Hilbert spaces of hydrogen atoms. One hydrogen atom is assigned to every plaquette of the lattice. The SU(2) gauge theory loop basis states over a plaquette are the bound energy eigenstates $|n l m>$ of the corresponding hydrogen atom. The Wigner couplings of these hydrogen atom energy eigenstates on different plaquettes provide a complete SU(2) gauge theory loop basis on the entire lattice. The loop basis is invariant under simultaneous rotations of all hydrogen atoms. The dual description of this basis diagonalizes all Wilson loop operators and is given in terms of hyperspherical harmonics on the SU(2) group manifold $S^3$. The SU(2) loop dynamics is governed by a "SU(2) spin Hamiltonian" without any gauge fields. The relevance of the hydrogen atom basis and its dynamical symmetry group SO(4,2) in SU(2) loop dynamics in weak coupling continuum limit ($g^2\\rightarrow 0$) is emphasized.
New gauge boson searches at the Tevatron
Hewett, J.L. (Wisconsin Univ., Madison, WI (USA). Dept. of Physics); Rizzo, T.G. (Wisconsin Univ., Madison, WI (USA). Dept. of Physics Iowa State Univ. of Science and Technology, Ames, IA (USA))
1990-01-01T23:59:59.000Z
The discovery reach of the Tevatron in the 1990's for new gauge bosons which originate in a wide range of extensions to the Standard Model is obtained. Most searches make use of the conventional leptonic decay mode of the Z{prime}, whereas others require the observation of a dijet mass peak above the QCD background from hadronic decays. 10 refs., 3 figs.
ACCELERATION INDUCED SPIN ITS GAUGE GEOMETRY
Gerlach, Ulrich
@math.ohioÂstate.edu ABSTRACT Does there exist a purely quantum mechanical characterization of gravitation? To this end at each event. A unique and natural law of parallel transport of quantum states between different events conclusion that gravitation is to be identified with the gauge geometry of the group [SU(1; 1)] 1 . #12
EECBG Success Story: Software Helps Kentucky County Gauge Energy...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Software Helps Kentucky County Gauge Energy Use EECBG Success Story: Software Helps Kentucky County Gauge Energy Use July 27, 2010 - 1:00pm Addthis Lexington-Fayette Urban County,...
Lyapunov spectra in SU(2) lattice gauge theory
Gong, C. [Physics Department, Duke University, Durham, North Carolina 27708-0305 (United States)] [Physics Department, Duke University, Durham, North Carolina 27708-0305 (United States)
1994-03-01T23:59:59.000Z
We develop a method for calculating the Lyapunov characteristic exponents of lattice gauge theories. The complete Lyapunov spectrum of SU(2) gauge theory is obtained and Kolmogorov-Sinai entropy is calculated. Rapid convergence with lattice size is found.
On the Definition of Gauge Field Operators in Lattice Gauge-Fixed Theories
L. Giusti; M. L. Paciello; S. Petrarca; B. Taglienti; M. Testa
1998-03-26T23:59:59.000Z
We address the problem of defining the gauge four-potential on the lattice, in terms of the natural link variables. Different regularized definitions are shown, through non perturbative numerical computation, to converge towards the same continuum renormalized limit.
An exact RG formulation of quantum gauge theory
Tim R. Morris
2001-02-19T23:59:59.000Z
A gauge invariant Wilsonian effective action is constructed for pure SU(N) Yang-Mills theory by formulating the corresponding flow equation. Manifestly gauge invariant calculations can be performed i.e. without gauge fixing or ghosts. Regularisation is implemented in a novel way which realises a spontaneously broken SU(N|N) supergauge theory. As an example we sketch the computation of the one-loop beta function, performed for the first time without any gauge fixing.
A Generalized Maximal Abelian Gauge in SU(3) Lattice Gauge Theory
Tucker, W W; Tucker, William W.; Stack, John D.
2002-01-01T23:59:59.000Z
We introduce a generalized Maximum Abelian Gauge (MAG). We work with this new gauge on 12^4 lattices for beta=5.7,5.8 and 16^4 lattices for beta=5.9,6.0. We also introduce a form of abelian projection related to the generalized MAG. We measure U(1)xU(1) wilson loops and single color magnetic current densities.
Gauge theories in noncommutative geometry December 7, 2011
Paris-Sud XI, Université de
permit to define noncommutative gauge field theories. In particular, we emphasize the theory of noncom of noncommutative gauge field theories are given to illustrate the constructions and to display some of the common differential structures [2123; 27; 28; 30; 63; 65]. However, all the noncommutative gauge field theories
Light-induced gauge fields for ultracold atoms
N. Goldman; G. Juzeliunas; P. Ohberg; I. B. Spielman
2014-12-12T23:59:59.000Z
Gauge fields are central in our modern understanding of physics at all scales. At the highest energy scales known, the microscopic universe is governed by particles interacting with each other through the exchange of gauge bosons. At the largest length scales, our universe is ruled by gravity, whose gauge structure suggests the existence of a particle - the graviton - that mediates the gravitational force. At the mesoscopic scale, solid-state systems are subjected to gauge fields of different nature: materials can be immersed in external electromagnetic fields, but they can also feature emerging gauge fields in their low-energy description. In this review, we focus on another kind of gauge field: those engineered in systems of ultracold neutral atoms. In these setups, atoms are suitably coupled to laser fields that generate effective gauge potentials in their description. Neutral atoms "feeling" laser-induced gauge potentials can potentially mimic the behavior of an electron gas subjected to a magnetic field, but also, the interaction of elementary particles with non-Abelian gauge fields. Here, we review different realized and proposed techniques for creating gauge potentials - both Abelian and non-Abelian - in atomic systems and discuss their implication in the context of quantum simulation. While most of these setups concern the realization of background and classical gauge potentials, we conclude with more exotic proposals where these synthetic fields might be made dynamical, in view of simulating interacting gauge theories with cold atoms.
A little rain doesn't fix it: Farmers and ranchers remain cautious as drought continues
Kalisek, Danielle
2012-01-01T23:59:59.000Z
and climate, along with the #17;#19;.#16;#25; billion of agricultural losses in #25;#24;#23;#23; plus crop, hay and livestock losses, leave the question: What is the outlook for agricultural crops, forage and livestock this year? Agricultural outlook ?It... rain doesn?t #30;x it continued Forage outlook #31;e drought took a toll on pastures, leaving most ranchers without any hay to cut and bare spots in the forage for livestock. ?A lot of our pastures, speci#28;cally hay meadows, were probably...
Rain or Shine, Students Keep Their Race Cars Going - News Feature | NREL
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5(Million Cubic Feet) Oregon (Including Vehicle Fuel) (Million Cubic Feet)setsManagementProtonQ1FY14 1 SummaryAOT: LANLRadorrletry P. G.reportsRain
Review of Lattice Supersymmetry and Gauge-Gravity Duality
Joseph, Anosh
2015-01-01T23:59:59.000Z
We review the status of recent investigations on validating the gauge-gravity duality conjecture through numerical simulations of strongly coupled maximally supersymmetric thermal gauge theories. In the simplest setting, the gauge-gravity duality connects systems of D0-branes and black hole geometries at finite temperature to maximally supersymmetric gauged quantum mechanics at the same temperature. Recent simulations show that non-perturbative gauge theory results give excellent agreement with the quantum gravity predictions, thus proving strong evidence for the validity of the duality conjecture and more insight into quantum black holes and gravity.
Gauge Potential Formulations of the Spin Hall Effect in Graphene
O. F. Dayi; E. Yunt
2011-05-27T23:59:59.000Z
Two different gauge potential methods are engaged to calculate explicitly the spin Hall conductivity in graphene. The graphene Hamiltonian with spin-orbit interaction is expressed in terms of kinematic momenta by introducing a gauge potential. A formulation of the spin Hall conductivity is established by requiring that the time evolution of this kinematic momentum vector vanishes. We then calculated the conductivity employing the Berry gauge fields. We show that both of the gauge fields can be deduced from the pure gauge field arising from the Foldy-Wouthuysen transformations.
Review of Lattice Supersymmetry and Gauge-Gravity Duality
Anosh Joseph
2015-09-04T23:59:59.000Z
We review the status of recent investigations on validating the gauge-gravity duality conjecture through numerical simulations of strongly coupled maximally supersymmetric thermal gauge theories. In the simplest setting, the gauge-gravity duality connects systems of D0-branes and black hole geometries at finite temperature to maximally supersymmetric gauged quantum mechanics at the same temperature. Recent simulations show that non-perturbative gauge theory results give excellent agreement with the quantum gravity predictions, thus proving strong evidence for the validity of the duality conjecture and more insight into quantum black holes and gravity.
GAUGE INVARIANCE IN A Z2 HAMILTONIAN LATTICE GUAGE THEORY.
SUGIHARA, T.
2005-07-25T23:59:59.000Z
We propose an efficient variational method for Z{sub 2} lattice gauge theory based on the matrix product ansatz. The method is applied to ladder and square lattices. The Gauss law needs to be imposed on quantum states to guarantee gauge invariance when one studies gauge theory in hamiltonian formalism. On the ladder lattice, we identify gauge invariant low-lying states by evaluating expectation values of the Gauss law operator after numerical diagonalization of the gauge hamiltonian. On the square lattice, the second order phase transition is well reproduced.
Conceptual Aspects of Gauge/Gravity Duality
de Haro, Sebastian; Butterfield, Jeremy
2015-01-01T23:59:59.000Z
We give an introductory review of gauge/gravity duality, and associated ideas of holography, emphasising the conceptual aspects. The opening Sections gather the ingredients, viz. anti-de Sitter spacetime, conformal field theory and string theory, that we need for presenting, in Section 5, the central and original example: Maldacena's AdS/CFT correspondence. Sections 6 and 7 develop the ideas of this example, also in applications to condensed matter systems, QCD, and hydrodynamics. Sections 8 and 9 discuss the possible extensions of holographic ideas to de Sitter spacetime and to black holes. Section 10 discusses the bearing of gauge/gravity duality on two philosophical topics: the equivalence of physical theories, and the idea that spacetime, or some features of it, are emergent.
Matrix product states for gauge field theories
Boye Buyens; Jutho Haegeman; Karel Van Acoleyen; Henri Verschelde; Frank Verstraete
2014-11-03T23:59:59.000Z
The matrix product state formalism is used to simulate Hamiltonian lattice gauge theories. To this end, we define matrix product state manifolds which are manifestly gauge invariant. As an application, we study 1+1 dimensional one flavour quantum electrodynamics, also known as the massive Schwinger model, and are able to determine very accurately the ground state properties and elementary one-particle excitations in the continuum limit. In particular, a novel particle excitation in the form of a heavy vector boson is uncovered, compatible with the strong coupling expansion in the continuum. We also study non-equilibrium dynamics by simulating the real-time evolution of the system induced by a quench in the form of a uniform background electric field.
Viable axion from gauged flavor symmetries
Berenstein, David; Perkins, Erik [Department of Physics, University of California, Santa Barbara, California 93106 (United States)
2010-11-15T23:59:59.000Z
We consider a string-inspired nonsupersymmetric extension of the standard model with gauged anomalous U(1) flavor symmetries. Consistency requires the Green-Schwarz (GS) mechanism to cancel mixed anomalies. The additional required scalars provide Stueckelberg masses for the Z{sup '} particles associated to the gauged flavor symmetry, so they decouple at low energies. Our models also include a complex scalar field {phi} to generate Froggatt-Nielsen mass terms for light particles, giving a partial solution to the fermion mass problem. A residual approximate (anomalous) global symmetry survives at low energies. The associated pseudo-Goldstone mode is the phase of the {phi} scalar field, and it becomes the dominant contribution to the physical axion. An effective field theory analysis that includes neutrino masses gives a prediction for the axion decay constant. We find a simple model where the axion decay constant is in the center of the allowed window.
Tensor gauge field localization in branes
Tahim, M. O. [Departamento de Fisica, Universidade Federal do Ceara, C.P. 6030, 60455-760 Fortaleza, Ceara (Brazil); Departamento de Ciencias da Natureza, Faculdade de Ciencias, Educacao e Letras do Sertao Central (FECLESC), Universidade Estadual do Ceara, 63900-000 Quixada, Ceara (Brazil); Cruz, W. T. [Departamento de Fisica, Universidade Federal do Ceara, C.P. 6030, 60455-760 Fortaleza, Ceara (Brazil); Centro Federal de Educacao Tecnologica do Ceara (CEFETCE), Unidade Descentralizada de Juazeiro do Norte, 63040-000 Juazeiro do Norte, Ceara (Brazil); Almeida, C. A. S. [Departamento de Fisica, Universidade Federal do Ceara, C.P. 6030, 60455-760 Fortaleza, Ceara (Brazil)
2009-04-15T23:59:59.000Z
In this work we study localization of a Kalb-Ramond tensorial gauge field on a membrane described by real scalar fields. The membrane is embedded in an AdS-type five-dimensional bulk space, which mimics a Randall-Sundrum scenario. First, we consider a membrane described by only a single real scalar field. In that scenario we find that there is no localized tensorial zero mode. When we take into account branes described by two real scalar fields with internal structures, we obtain again a nonlocalized zero mode for a Kalb-Ramond tensorial gauge field. After modifying our model of one single scalar field by coupling the dilaton to the Kalb-Ramond field, we find that this result is changed. Furthermore, we analyze Kaluza-Klein massive modes and resonance structures.
Jet fragmentation and gauge/string duality
Yoshitaka Hatta; Toshihiro Matsuo
2008-05-27T23:59:59.000Z
We consider an analog of e^+e^- annihilation in gauge theories which have a dual string description in asymptotically AdS_5 space and discuss the nature of jet fragmentation. We construct the timelike anomalous dimension which governs the scale dependence of the fragmentation function. In the limit of infinite 't Hooft coupling, the average multiplicity rises linearly with the energy and the inclusive spectrum is peaked at the kinematical boundary.
Revisiting the gauge fields of strained graphene
Iorio, Alfredo
2015-01-01T23:59:59.000Z
We join the on-going debate on the nature of the gauge fields arising when straining graphene, hopefully adding clarity to the debate, especially in view of the use of graphene as a table-top indirect laboratory for high energy physics. We identify two types of gauge fields: the first one arising from a trivial spin-connection of zero Riemann tensor, that gives a pure-gauge Weyl field; the second one originating from peculiar structure of the graphene honeycomb, whose non-triviality is encoded in a special rank-three tensor. The former cannot give a nonzero "pseudo-magnetic field", but the relativistic approach behind it explains non-isotropic, space-dependent Fermi velocity. The latter has, in general, nonzero associated field-strength, and gives an example of a low-energy (continuum limit) relic of a high-energy (lattice) structure, a feature that makes it interesting for explorations of fundamental physics scenarios with similar behaviors. We conclude by briefly pointing to some of those scenarios.
Revisiting the gauge fields of strained graphene
Alfredo Iorio; Pablo Pais
2015-08-04T23:59:59.000Z
We join the on-going debate on the nature of the gauge fields arising when straining graphene, hopefully adding clarity to the debate, especially in view of the use of graphene as a table-top indirect laboratory for high energy physics. We identify two types of gauge fields: the first one arising from a trivial spin-connection of zero Riemann tensor, that gives a pure-gauge Weyl field; the second one originating from peculiar structure of the graphene honeycomb, whose non-triviality is encoded in a special rank-three tensor. The former cannot give a nonzero "pseudo-magnetic field", but the relativistic approach behind it explains non-isotropic, space-dependent Fermi velocity. The latter has, in general, nonzero associated field-strength, and gives an example of a low-energy (continuum limit) relic of a high-energy (lattice) structure, a feature that makes it interesting for explorations of fundamental physics scenarios with similar behaviors. We conclude by briefly pointing to some of those scenarios.
Overview of the oxidation and scavenging characteristics of April rains (OSCAR) experiment
Easter, R.C.; Dana, M.T.; Thorp, J.M.; Busness, K.M.; Hales, J.M.; Raynor, G.S.; Benkovitz, C.M.; Tanner, R.L.; Shannon, J.D.
1984-04-01T23:59:59.000Z
The OSCAR (Oxidation and Scavenging Characteristics of April Rains) field experiment was conducted in April, 1981, as part of the MAP3S/RAINE program. The OSCAR study was designed to provide detailed characterizations of the physicochemical and dynamical features of selected cyclonic storm systems as they traversed the eastern U.S. Major experiment components included sequential precipitation chemistry measurements, aircraft measurements both in cloud and in clear air in storm inflow regions, surface-level air chemistry measurements, and supporting meteorological measurements. The precipitation chemisty network consisted of an intermediate-density network with 37 sampling sites covering the region from southern Ontario to Tennessee and from Illinois to New Hampshire, and a high-density network with 47 sampling sites located in a 100 by 100 km area in northeast Indiana. A total of four storm events were studied during the experiment. The report describes the design and operational aspects for the high-density and intermediate-density components of the experiment, and the composition of the integrated OSCAR data set which has been developed. A synoptic meteorological description of the four storm events studied during OSCAR is also provided. 17 references, 13 figures, 8 tables.
The red rain phenomenon of Kerala and its possible extraterrestrial origin
Louis, G; Louis, Godfrey
2006-01-01T23:59:59.000Z
A red rain phenomenon occurred in Kerala, India starting from 25th July 2001, in which the rainwater appeared coloured in various localized places that are spread over a few hundred kilometers in Kerala. Maximum cases were reported during the first 10 days and isolated cases were found to occur for about 2 months. The striking red colouration of the rainwater was found to be due to the suspension of microscopic red particles having the appearance of biological cells. These particles have no similarity with usual desert dust. An estimated minimum quantity of 50,000 kg of red particles has fallen from the sky through red rain. An analysis of this strange phenomenon further shows that the conventional atmospheric transport processes like dust storms etc. cannot explain this phenomenon. The electron microscopic study of the red particles shows fine cell structure indicating their biological cell like nature. EDAX analysis shows that the major elements present in these cell like particles are carbon and oxygen. St...
Acid rain in China. Rapid industrialization has put citizens and ecosystems at risk
Thorjoern Larssen; Espen Lydersen; Dagang Tang [and others] [Norwegian Institute for Water Research and University of Oslo, Oslo (Norway)
2006-01-15T23:59:59.000Z
Acid rain emerged as an important environmental problem in China in the late 1970s. Many years of record economic growth have been accompanied by increased energy demand, greater coal combustion, and larger emissions of pollutants. As a result of significant emissions and subsequent deposition of sulfur, widespread acid rain is observed in southern and southwestern China. In fact, the deposition of sulfur is in some places higher than what was reported from the 'black triangle' in central Europe in the early 1980s. In addition, nitrogen is emitted from agriculture, power production, and a rapidly increasing number of cars. As a result, considerable deposition of pollutants occurs in forested areas previously thought to be pristine. Little is known about the effects of acid deposition on terrestrial and aquatic ecosystems in China. This article presents the current situation and what to expect in the future, largely on the basis of results from a five-year Chinese-Norwegian cooperative project. In the years ahead, new environmental challenges must be expected if proper countermeasures are not put into place. 31 refs., 4 figs.
Modelling chemical degradation of concrete during leaching with rain and soil water types
Jacques, D., E-mail: djacques@sckcen.b [Belgian Nuclear Research Centre (SCK-CEN), Institute for Environment, Health, and Safety, Boeretang 200, B-2400 Mol (Belgium); Wang, L.; Martens, E.; Mallants, D. [Belgian Nuclear Research Centre (SCK-CEN), Institute for Environment, Health, and Safety, Boeretang 200, B-2400 Mol (Belgium)
2010-08-15T23:59:59.000Z
Percolation of external water through concrete results in the degradation of cement and changes the concrete pore water and solid phase composition. The assessment of long-term degradation of concrete is possible by means of model simulation. This paper describes simulations of chemical degradation of cement for different types of rain and soil water at an ambient earth surface temperature (10 {sup o}C). Rain and soil water types were derived using generic equations and measurement of atmospheric boundary conditions representative for North-Belgium. An up-to-date and consistent thermodynamic model is used to calculate the geochemical changes during chemical degradation of the concrete. A general pattern of four degradation stages was simulated with the third stage being the geochemically most complex stage involving reactions with calcium-silicate hydrates, AFm and AFt phases. Whereas the sequence of the dissolution reactions was relatively insensitive to the composition of the percolating water, the duration of the different reactions depends strongly on the percolating water composition. Major identified factors influencing the velocity of cement degradation are the effect of dry deposition and biological activity increasing the partial pressure of CO{sub 2(g)} in the soil air phase (and thus increasing the inorganic carbon content in the percolating water). Soil weathering processes have only a minor impact, at least for the relatively inert sandy material considered in this study.
Rain-Induced Increase in Background Radiation Detected by Radiation Portal Monitors
Hausladen, Paul [ORNL; Blessinger, Christopher S [ORNL; Guzzardo, Tyler [ORNL; Livesay, Jake [ORNL
2012-07-01T23:59:59.000Z
A complete understanding of both the steady state and transient background measured by Radiation Portal Monitors (RPMs) is essential to predictable system performance, as well as maximization of detection sensitivity. To facilitate this understanding, a test bed for the study of natural background in RPMs has been established at the Oak Ridge National Laboratory. This work was performed in support of the Second Line of Defense Program's mission to detect the illicit movement of nuclear material. In the present work, transient increases in gamma ray counting rates in RPMs due to rain are investigated. The increase in background activity associated with rain, which has been well documented in the field of environmental radioactivity, originates from the atmospheric deposition of two radioactive daughters of radon-222, namely lead-214 and bismuth-214 (henceforth {sup 222}Rn, {sup 214}Pb and {sup 214}Bi). In this study, rainfall rates recorded by a co-located weather station are compared with RPM count rates and High Purity Germanium spectra. The data verifies these radionuclides are responsible for the dominant transient natural background fluctuations in RPMs. Effects on system performance and potential mitigation strategies are discussed.
Local Gauge Transformation for the Quark Propagator in an SU(N) Gauge Theory
Aslam, M Jamil; Gutierrez-Guerrero, L X
2015-01-01T23:59:59.000Z
In an SU(N) gauge field theory, the n-point Green functions, namely, propagators and vertices, transform under the simultaneous local gauge variations of the gluon vector potential and the quark matter field in such a manner that the physical observables remain invariant. In this article, we derive this intrinsically non perturbative transformation law for the quark propagator within the system of covariant gauges. We carry out its explicit perturbative expansion till O(g_s^6) and, for some terms, till O(g_s^8). We study the implications of this transformation for the quark-anti-quark condensate, multiplicative renormalizability of the massless quark propagator, as well as its relation with the quark-gluon vertex at the one-loop order. Setting the color factors C_F=1 and C_A=0, Landau-Khalatnikov-Fradkin transformation for the abelian case of quantum electrodynamics is trivially recovered.
Path Integral Quantization of Quantum Gauge General Relativity
Ning Wu
2008-12-16T23:59:59.000Z
Path integral quantization of quantum gauge general relativity is discussed in this paper. First, we deduce the generating functional of green function with external fields. Based on this generating functional, the propagators of gravitational gauge field and related ghost field are deduced. Then, we calculate Feynman rules of various interaction vertices of three or four gravitational gauge fields and vertex between ghost field and gravitational gauge field. Results in this paper are the bases of calculating vacuum polarization of gravitational gauge field and vertex correction of gravitational couplings in one loop diagram level. As we have pointed out in previous paper, quantum gauge general relativity is perturbative renormalizable, and a formal proof on its renormalizability is also given in the previous paper. Next step, we will calculate one-loop and two-loop renormalization constant, and to prove that the theory is renormalizable in one-loop and two-loop level by direct calculations.
Vortex and gap generation in gauge models of graphene
O. Oliveira; C. E. Cordeiro; A. Delfino; W. de Paula; T. Frederico
2011-04-22T23:59:59.000Z
Effective quantum field theoretical continuum models for graphene are investigated. The models include a complex scalar field and a vector gauge field. Different gauge theories are considered and their gap patterns for the scalar, vector, and fermion excitations are investigated. Different gauge groups lead to different relations between the gaps, which can be used to experimentally distinguish the gauge theories. In this class of models the fermionic gap is a dynamic quantity. The finite-energy vortex solutions of the gauge models have the flux of the "magnetic field" quantized, making the Bohm-Aharonov effect active even when external electromagnetic fields are absent. The flux comes proportional to the scalar field angular momentum quantum number. The zero modes of the Dirac equation show that the gauge models considered here are compatible with fractionalization.
Noncommutative geometric gauge theory from superconnections
Lee, C Y
1996-01-01T23:59:59.000Z
Noncommutative geometric gauge theory is reconstructed based on the superconnection concept. The bosonic action of the Connes-Lott model including the symmetry breaking Higgs sector is obtained by using a new generalized derivative, which consists of the usual 1-form exterior derivative plus an extra element called {\\it matrix derivative}, for curvatures. We first derive the matrix derivative based on superconnections then show how the matrix derivative can give rise to spontaneous symmetry breaking. We comment on the correspondence between the generalized derivative and the generalized Dirac operator of the Connes-Lott model.
Continuum regularization of gauge theory with fermions
Chan, H.S.
1987-03-01T23:59:59.000Z
The continuum regularization program is discussed in the case of d-dimensional gauge theory coupled to fermions in an arbitrary representation. Two physically equivalent formulations are given. First, a Grassmann formulation is presented, which is based on the two-noise Langevin equations of Sakita, Ishikawa and Alfaro and Gavela. Second, a non-Grassmann formulation is obtained by regularized integration of the matter fields within the regularized Grassmann system. Explicit perturbation expansions are studied in both formulations, and considerable simplification is found in the integrated non-Grassmann formalism.
Noncommutative Geometric Gauge Theory from Superconnections
Chang-Yeong Lee
1997-09-02T23:59:59.000Z
Noncommutative geometric gauge theory is reconstructed based on the superconnection concept. The bosonic action of the Connes-Lott model including the symmetry breaking Higgs sector is obtained by using a new generalized derivative, which consists of the usual 1-form exterior derivative plus an extra element called the matrix derivative, for the curvatures. We first derive the matrix derivative based on superconnections and then show how the matrix derivative can give rise to spontaneous symmetry breaking. We comment on the correspondence between the generalized derivative and the generalized Dirac operator of the Connes-Lott model.
Energy-momentum tensors in gauge theory
G. Sardanashvily
2002-07-02T23:59:59.000Z
In field theory on a fibre bundle Y->X, an energy-momentum current is associated to a lift onto Y of a vector field on X. Such a lift by no means is unique, and contains a vertical part. It follows that: (i) there are a set of different energy-momentum currents, (ii) the Noether part of an energy-momentum current can not be taken away, (iii) if a Lagrangian is not gauge-invariant, the energy-momentum fails to be conserved.
Ning Wu
2012-07-11T23:59:59.000Z
When we discuss problems on gravity, we can not avoid some fundamental physical problems, such as space-time, inertia, and inertial reference frame. The goal of this paper is to discuss the logic system of gravity theory and the problems of space-time, inertia, and inertial reference frame. The goal of this paper is to set up the theory on space-time in gauge theory of gravity. Based on this theory, it is possible for human kind to manipulate physical space-time on earth, and produce a machine which can physically prolong human's lifetime.
Massive Gauge Fields and the Planck Scale
Acosta, G D
2004-01-01T23:59:59.000Z
The present work is devoted to massive gauge fields in special relativity with two fundamental constants-the velocity of light, and the Planck length, so called doubly special relativity (DSR). The two invariant scales are accounted for by properly modified boost parameters. Within above framework we construct the vector potential as the (1/2,0)x(0,1/2) direct product, build the associated field strength tensor together with the Dirac spinors and use them to calculate various observables as functions of the Planck length.
Massive Gauge Fields and the Planck Scale
G. D. Acosta; M. Kirchbach
2004-11-09T23:59:59.000Z
The present work is devoted to massive gauge fields in special relativity with two fundamental constants-the velocity of light, and the Planck length, so called doubly special relativity (DSR). The two invariant scales are accounted for by properly modified boost parameters. Within above framework we construct the vector potential as the (1/2,0)x(0,1/2) direct product, build the associated field strength tensor together with the Dirac spinors and use them to calculate various observables as functions of the Planck length.
Cosmological String Backgrounds from Gauged WZW Models
C. Kounnas; D. Luest
1992-05-18T23:59:59.000Z
We discuss the four-dimensional target-space interpretation of bosonic strings based on gauged WZW models, in particular of those based on the non-compact coset space $SL(2,{\\bf R})\\times SO(1,1)^2 /SO(1,1)$. We show that these theories lead, apart from the recently broadly discussed black-hole type of backgrounds, to cosmological string backgrounds, such as an expanding Universe. Which of the two cases is realized depends on the sign of the level of the corresponding Kac-Moody algebra. We discuss various aspects of these new cosmological string backgrounds.
QCD plasma parameters and the gauge-dependent gluon propagator
Kobes, R.; Kunstatter, G.; Rebhan, A. (Department of Physics, University of Winnipeg, 515 Portage Avenue, Winnipeg, Manitoba (Canada) Institut fuer Theoretische Physik, Technische Universitaet Wien, Wiedner Haupstrasse 8-10, A-1040 Vienna (Austria))
1990-06-18T23:59:59.000Z
We derive the Ward identities that determine the gauge dependence of the QCD dispersion relations obtained from the ordinary gluon propagator in a certain class of gauges. These identities hold for complex structure functions at both zero and finite temperature. A direct consequence of our analysis is that the gauge dependence of the gluon-plasma damping constant obtained in recent one-loop calculations is due to an inconsistent approximation scheme.
Multiple choice of gauge generators and consistency of interactions
S. L. Lyakhovich; A. A. Sharapov
2014-08-07T23:59:59.000Z
It is usually assumed that any consistent interaction either deforms or retains the gauge symmetries of the corresponding free theory. We propose a simple model where an obvious irreducible gauge symmetry does not survive an interaction, while the interaction is consistent as it preserves the number of physical degrees of freedom. The model turns out admitting a less obvious reducible set of gauge generators which is compatible with the interaction and smooth in coupling constant. Possible application to gravity models is discussed.
Yong Tang; Yue-Liang Wu
2011-10-30T23:59:59.000Z
We perform an explicit one-loop calculation for the gravitational contributions to the two-, three- and four-point gauge Green's functions with paying attention to the quadratic divergences. It is shown for the first time in the diagrammatic calculation that the Slavnov-Taylor identities are preserved even if the quantum graviton effects are included at one-loop level, such a conclusion is independent of the choice of regularization schemes. We also present a regularization scheme independent calculation based on the gauge condition independent background field framework of Vilkovisky-DeWitt's effective action with focusing on both the quadratic divergence and quartic divergence that is not discussed before. With the harmonic gauge condition, the results computed by using the traditional background field method can consistently be recovered from the Vilkovisky-DeWitt's effective action approach by simply taking a limiting case, and are found to be the same as the ones yielded by the diagrammatic calculation. As a consequence, in all the calculations, the symmetry-preserving and divergent-behavior-preserving loop regularization method can consistently lead to a nontrivial gravitational contribution to the gauge coupling constant with an asymptotic free power-law running at one loop near the Planck scale.
Traces of Radioactive 131I in Rain Water Samples in Romania
Margineanu, Romul; Apostu, Ana; Gomoiu, Claudia
2011-01-01T23:59:59.000Z
Measurements of I-131 (T1/2 = 8.04 days) have been performed in IFIN-HH's underground laboratory situated in Unirea salt mine from Slanic-Prahova, Romania. The rain water samples were collected in March 27th in Brasov and March 27th and 29th in Slanic. The samples were measured using a high resolution gamma-ray spectrometer equipped with a GeHP detector having a FWHM = 1.80 keV at 1332.48 keV at the second Co-60 gammaray, and a relative efficiency of 22.8 %. The results show a specific activity of I-131 of 0.35 \\pm 0.04 Bq/dm^3 in Brasov and 0.39 \\pm 0.04 Bq/dm^3, 0.13 \\pm 0.03 Bq/dm^3 and 0.71 \\pm 0.06 Bq/dm^3 in Slanic.
Multiple antibiotic resistant Escherichia coli from a tropical rain forest stream
Carrasco, C.E.; Alvarez, H.J.; Ortiz, N.; Bisbal, M.; Arias, W.; Baerga, C. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico). Dept. of Biology; Hazen, T.C. [E.I. DuPont de Nemours and Co., Aiken, SC (United States). Savannah River Lab.
1988-12-31T23:59:59.000Z
High densities of fecal coliforms were obtained from a pristine site and sewage contaminated site in a tropical rain forest watershed in Puerto Rico. Confirmation of fecal coliform isolates as Escherichia coli was significantly lower than for temperate waters. Antibiotic resistance and multiple antibiotic resistance were common for isolates at both sites; however, the site receiving sewage effluent had a greater proportion of multiple antibiotic resistant isolates. R. plasmids were recovered from 4 MAR isolates, 2 from each site. All recovered plasmids were approximately 1 kilobase. The recovered plasmid were also capable of transforming E. coli HB101 in vitro. The high concentrations of enterobacteriaceae, small R-plasmid size, R-plasmid transformability, and long term survival of fecal origin bacteria in tropical freshwater environments give increasing importance to adequate sewage treatment, and better indicator monitoring methods for tropical areas.
Non-Abelian discrete gauge symmetries in F-theory
Thomas W. Grimm; Tom G. Pugh; Diego Regalado
2015-04-23T23:59:59.000Z
The presence of non-Abelian discrete gauge symmetries in four-dimensional F-theory compactifications is investigated. Such symmetries are shown to arise from seven-brane configurations in genuine F-theory settings without a weak string coupling description. Gauge fields on mutually non-local seven-branes are argued to gauge both R-R and NS-NS two-form bulk axions. The gauging is completed into a generalisation of the Heisenberg group with either additional seven-brane gauge fields or R-R bulk gauge fields. The former case relies on having seven-brane fluxes, while the latter case requires torsion cohomology and is analysed in detail through the M-theory dual. Remarkably, the M-theory reduction yields an Abelian theory that becomes non-Abelian when translated into the correct duality frame to perform the F-theory limit. The reduction shows that the gauge coupling function depends on the gauged scalars and transforms non-trivially as required for the groups encountered. This field dependence agrees with the expectations for the kinetic mixing of seven-branes and is unchanged if the gaugings are absent.
Aspects of 7d and 6d gauged supergravities
Jong, Der-Chyn
2009-05-15T23:59:59.000Z
reduction to yield a matter coupled gauged supergravity in six dimensions with 8 real supersymmetry. Solving these conditions we nd that the SO(2;2) and SO(3;1) gauged 7D supergravities give a U(1)R, and the SO(2;1) gauged 7D supergravity gives an Sp(1)R... such that a R-symmetry gauging survives. These are referred to as the SO(3;1);SO(2;1) and SO(2;2) models, in which these groups re- fer to isometries of manifolds parametrized by the scalar elds that arise in the 7D theory. The 6D models we obtain describe...
Aspects of 7D and 6D gauged supergravities
Jong, Der-Chyn
2008-10-10T23:59:59.000Z
reduction to yield a matter coupled gauged supergravity in six dimensions with 8 real supersymmetry. Solving these conditions we nd that the SO(2;2) and SO(3;1) gauged 7D supergravities give a U(1)R, and the SO(2;1) gauged 7D supergravity gives an Sp(1)R... such that a R-symmetry gauging survives. These are referred to as the SO(3;1);SO(2;1) and SO(2;2) models, in which these groups re- fer to isometries of manifolds parametrized by the scalar elds that arise in the 7D theory. The 6D models we obtain describe...
Reply to 'Comment on 'Noncommutative gauge theories and Lorentz symmetry''
Banerjee, Rabin; Chakraborty, Biswajit; Kumar, Kuldeep [S. N. Bose National Centre for Basic Sciences, JD Block, Sector 3, Salt Lake, Kolkata 700098 (India); Department of Physics, Panjab University, Chandigarh 160014 (India)
2008-02-15T23:59:59.000Z
This is a reply to the preceding 'Comment on 'Noncommutative gauge theories and Lorentz symmetry'', Phys. Rev. D 77, 048701 (2008) by Alfredo Iorio.
Anisotropic inflation with non-abelian gauge kinetic function
Murata, Keiju [DAMTP, University of Cambridge, Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Soda, Jiro, E-mail: K.Murata@damtp.cam.ac.uk, E-mail: jiro@tap.scphys.kyoto-u.ac.jp [Department of Physics, Kyoto University, Kyoto, 606-8502 (Japan)
2011-06-01T23:59:59.000Z
We study an anisotropic inflation model with a gauge kinetic function for a non-abelian gauge field. We find that, in contrast to abelian models, the anisotropy can be either a prolate or an oblate type, which could lead to a different prediction from abelian models for the statistical anisotropy in the power spectrum of cosmological fluctuations. During a reheating phase, we find chaotic behaviour of the non-abelian gauge field which is caused by the nonlinear self-coupling of the gauge field. We compute a Lyapunov exponent of the chaos which turns out to be uncorrelated with the anisotropy.
Aspects of 7D and 6D gauged supergravities
Jong, Der-Chyn
2008-10-10T23:59:59.000Z
reduction to yield a matter coupled gauged supergravity in six dimensions with 8 real supersymmetry. Solving these conditions we nd that the SO(2;2) and SO(3;1) gauged 7D supergravities give a U(1)R, and the SO(2;1) gauged 7D supergravity gives an Sp(1)R... such that a R-symmetry gauging survives. These are referred to as the SO(3;1);SO(2;1) and SO(2;2) models, in which these groups re- fer to isometries of manifolds parametrized by the scalar elds that arise in the 7D theory. The 6D models we obtain describe...
Aspects of 7d and 6d gauged supergravities
Jong, Der-Chyn
2009-05-15T23:59:59.000Z
reduction to yield a matter coupled gauged supergravity in six dimensions with 8 real supersymmetry. Solving these conditions we nd that the SO(2;2) and SO(3;1) gauged 7D supergravities give a U(1)R, and the SO(2;1) gauged 7D supergravity gives an Sp(1)R... such that a R-symmetry gauging survives. These are referred to as the SO(3;1);SO(2;1) and SO(2;2) models, in which these groups re- fer to isometries of manifolds parametrized by the scalar elds that arise in the 7D theory. The 6D models we obtain describe...
Gauge Theories on an Interval: Unitarity Without a Higgs Boson
Csaki, Csaba; Grojean, Christophe; Murayama, Hitoshi; Luigi, Pilo; Terning, John
2004-01-01T23:59:59.000Z
breaking without a Higgs boson. Gauge Theories on anscattering amplitude. The Higgs boson is localized at y = ?Rreal scalar ?eld, the Higgs boson. At tree level, the
Week 4, Rain in my Brain On top of the Harbor Cone, Otago Peninsula, Pacific Ocean in the distance.
Bardsley, John
Week 4, Rain in my Brain On top of the Harbor Cone, Otago Peninsula, Pacific Ocean in the distance of the ocean or of this beautiful city from on-high and it all comes back that we're here, a dream come true
Dew, fog, and rain as supplementary sources of water in south-western I. Lekoucha,b,c
Paris-Sud XI, Université de
-arid coastal areas of south-western north Africa could make dew water an interesting supplementary alternative1 Dew, fog, and rain as supplementary sources of water in south-western Morocco I. Lekoucha,b,c , M-00590605,version1-4May2011 Author manuscript, published in "Energy 36, 4 (2011) 2257-2265" DOI : 10.1016/j.energy
Thermalization in a Holographic Confining Gauge Theory
Takaaki Ishii; Elias Kiritsis; Christopher Rosen
2015-03-26T23:59:59.000Z
Time dependent perturbations of states in a 3+1 dimensional confining gauge theory are considered in the context of holography. The perturbations are induced by varying the gauge theory's coupling to a dimension three scalar operator in time. The dual gravitational theory belongs to a class of Einstein-dilaton theories which exhibit a mass gap at zero temperature and a first order deconfining phase transition at finite temperature. The perturbation is realized in various thermal bulk solutions by specifying time dependent boundary conditions on the scalar, and we solve the fully backreacted Einstein-dilaton equations of motion subject to these boundary conditions. We compute the characteristic time scale of many thermalization processes, noting that in every case we examine, this time scale is determined by the imaginary part of the lowest lying quasi-normal mode of the final state black brane. We quantify the dependence of this final state on parameters of the quench, and construct a dynamical phase diagram. Further support for a universal scaling regime in the abrupt quench limit is provided.
Thermalization in a Holographic Confining Gauge Theory
Ishii, Takaaki; Rosen, Christopher
2015-01-01T23:59:59.000Z
Time dependent perturbations of states in a 3+1 dimensional confining gauge theory are considered in the context of holography. The perturbations are induced by varying the gauge theory's coupling to a dimension three scalar operator in time. The dual gravitational theory belongs to a class of Einstein-dilaton theories which exhibit a mass gap at zero temperature and a first order deconfining phase transition at finite temperature. The perturbation is realized in various thermal bulk solutions by specifying time dependent boundary conditions on the scalar, and we solve the fully backreacted Einstein-dilaton equations of motion subject to these boundary conditions. We compute the characteristic time scale of many thermalization processes, noting that in every case we examine, this time scale is determined by the imaginary part of the lowest lying quasi-normal mode of the final state black brane. We quantify the dependence of this final state on parameters of the quench, and construct a dynamical phase diagram....
Exact Results in Supersymmetric Gauge Theories
Saulius Valatka
2014-12-31T23:59:59.000Z
In this thesis we discuss supersymmetric gauge theories, focusing on exact results achieved using methods of integrability. For the larger portion of the thesis we study the N=4 super Yang-Mills theory in the planar limit, a recurring topic being the Konishi anomalous dimension, which is roughly the analogue for the mass of the proton in quantum chromodynamics. The N=4 supersymmetric Yang-Mills theory is known to be integrable in the planar limit, which opens up a wealth of techniques one can employ in order to find results in this limit valid at any value of the coupling. We begin with perturbation theory where the integrability of the theory first manifests itself. Here we showcase the first exact result, the so-called slope function, which is the linear small spin expansion coefficient of the generalized Konishi anomalous dimension. We then move on to exact results mainly achieved using the novel quantum spectral curve approach, the method allowing one to find scaling dimensions of operators at arbitrary values of the coupling. As an example we find the second coefficient in the small spin expansion after the slope, which we call the curvature function. This allows us to extract non-trivial information about the Konishi operator. Methods of integrability are also applicable to other supersymmetric gauge theories such as ABJM, which in fact shares many similarities with N=4 super Yang-Mills. We briefly review these parallel developments in the last chapter of the thesis.
Nonextensive lattice gauge theories: algorithms and methods
Rafael B. Frigori
2014-04-26T23:59:59.000Z
High-energy phenomena presenting strong dynamical correlations, long-range interactions and microscopic memory effects are well described by nonextensive versions of the canonical Boltzmann-Gibbs statistical mechanics. After a brief theoretical review, we introduce a class of generalized heat-bath algorithms that enable Monte Carlo lattice simulations of gauge fields on the nonextensive statistical ensemble of Tsallis. The algorithmic performance is evaluated as a function of the Tsallis parameter q in equilibrium and nonequilibrium setups. Then, we revisit short-time dynamic techniques, which in contrast to usual simulations in equilibrium present negligible finite-size effects and no critical slowing down. As an application, we investigate the short-time critical behaviour of the nonextensive hot Yang-Mills theory at q- values obtained from heavy-ion collision experiments. Our results imply that, when the equivalence of statistical ensembles is obeyed, the long-standing universality arguments relating gauge theories and spin systems hold also for the nonextensive framework.
Bulk viscosity of gauge theory plasma at strong coupling
Alex Buchel
2007-09-01T23:59:59.000Z
We propose a lower bound on bulk viscosity of strongly coupled gauge theory plasmas. Using explicit example of the N=2^* gauge theory plasma we show that the bulk viscosity remains finite at a critical point with a divergent specific heat. We present an estimate for the bulk viscosity of QGP plasma at RHIC.
Non-Abelian discrete gauge symmetries in F-theory
Grimm, Thomas W; Regalado, Diego
2015-01-01T23:59:59.000Z
The presence of non-Abelian discrete gauge symmetries in four-dimensional F-theory compactifications is investigated. Such symmetries are shown to arise from seven-brane configurations in genuine F-theory settings without a weak string coupling description. Gauge fields on mutually non-local seven-branes are argued to gauge both R-R and NS-NS two-form bulk axions. The gauging is completed into a generalisation of the Heisenberg group with either additional seven-brane gauge fields or R-R bulk gauge fields. The former case relies on having seven-brane fluxes, while the latter case requires torsion cohomology and is analysed in detail through the M-theory dual. Remarkably, the M-theory reduction yields an Abelian theory that becomes non-Abelian when translated into the correct duality frame to perform the F-theory limit. The reduction shows that the gauge coupling function depends on the gauged scalars and transforms non-trivially as required for the groups encountered. This field dependence agrees with the exp...
A review on SUSY gauge theories on $S^3$
Kazuo Hosomichi
2015-07-04T23:59:59.000Z
This is the 9th article in the collection of reviews "Exact results on N=2 supersymmetric gauge theories", ed. J.Teschner. We review the exact computations in 3D N=2 supersymmetric gauge theories on the round or squashed $S^3$ and the relation between 3D partition functions and 4D superconformal indices.
On the WDVV equations in five-dimensional gauge theories
L. K. Hoevenaars; R. Martini
2003-01-15T23:59:59.000Z
It is well-known that the perturbative prepotentials of four-dimensional N=2 supersymmetric Yang-Mills theories satisfy the generalized WDVV equations, regardless of the gauge group. In this paper we study perturbative prepotentials of the five-dimensional theories for some classical gauge groups and determine whether or not they satisfy the WDVV system.
Lattice Gauge Fields and Discrete Noncommutative Yang-Mills Theory
J. Ambjorn; Y. M. Makeenko; J. Nishimura; R. J. Szabo
2000-04-21T23:59:59.000Z
We present a lattice formulation of noncommutative Yang-Mills theory in arbitrary even dimensionality. The UV/IR mixing characteristic of noncommutative field theories is demonstrated at a completely nonperturbative level. We prove a discrete Morita equivalence between ordinary Yang-Mills theory with multi-valued gauge fields and noncommutative Yang-Mills theory with periodic gauge fields. Using this equivalence, we show that generic noncommutative gauge theories in the continuum can be regularized nonperturbatively by means of {\\it ordinary} lattice gauge theory with 't~Hooft flux. In the case of irrational noncommutativity parameters, the rank of the gauge group of the commutative lattice theory must be sent to infinity in the continuum limit. As a special case, the construction includes the recent description of noncommutative Yang-Mills theories using twisted large $N$ reduced models. We study the coupling of noncommutative gauge fields to matter fields in the fundamental representation of the gauge group using the lattice formalism. The large mass expansion is used to describe the physical meaning of Wilson loops in noncommutative gauge theories. We also demonstrate Morita equivalence in the presence of fundamental matter fields and use this property to comment on the calculation of the beta-function in noncommutative quantum electrodynamics.
Gauge - invariant fluctuations of the metric in stochastic inflation
Mauricio Bellini
2000-01-07T23:59:59.000Z
I derive the stochastic equation for the perturbations of the metric for a gauge - invariant energy - momemtum - tensor (EMT) in stochastic inflation. A quantization for the field that describes the gauge - invariant perturbations for the metric is developed. In a power - law expansion for the universe the amplitude for these perturbations on a background metric could be very important in the infrared sector.
Tensor Networks for Lattice Gauge Theories with continuous groups
Luca Tagliacozzo; Alessio Celi; Maciej Lewenstein
2014-12-19T23:59:59.000Z
We discuss how to formulate lattice gauge theories in the Tensor Network language. In this way we obtain both a consistent truncation scheme of the Kogut-Susskind lattice gauge theories and a Tensor Network variational ansatz for gauge invariant states that can be used in actual numerical computation. Our construction is also applied to the simplest realization of the quantum link models/gauge magnets and provides a clear way to understand their microscopic relation with Kogut-Susskind lattice gauge theories. We also introduce a new set of gauge invariant operators that modify continuously Rokshar-Kivelson wave functions and can be used to extend the phase diagram of known models. As an example we characterize the transition between the deconfined phase of the $Z_2$ lattice gauge theory and the Rokshar-Kivelson point of the U(1) gauge magnet in 2D in terms of entanglement entropy. The topological entropy serves as an order parameter for the transition but not the Schmidt gap.
Quiver gauge theories and integrable lattice models
Junya Yagi
2015-06-30T23:59:59.000Z
We discuss connections between certain classes of supersymmetric quiver gauge theories and integrable lattice models from the point of view of topological quantum field theories (TQFTs). The relevant classes include 4d $\\mathcal{N} = 1$ theories known as brane box and brane tilling models, 3d $\\mathcal{N} = 2$ and 2d $\\mathcal{N} = (2,2)$ theories obtained from them by compactification, and 2d $\\mathcal{N} = (0,2)$ theories closely related to these theories. We argue that their supersymmetric indices carry structures of TQFTs equipped with line operators, and as a consequence, are equal to the partition functions of lattice models. The integrability of these models follows from the existence of extra dimension in the TQFTs, which emerges after the theories are embedded in M-theory. The Yang-Baxter equation expresses the invariance of supersymmetric indices under Seiberg duality and its lower-dimensional analogs.
OTDR strain gauge for smart skins
Kercel, S.W.
1993-09-01T23:59:59.000Z
Optical time-domain reflectometry (OTDR) is a simple and rugged technique for measuring quantities such as strain that affect the propagation of light in an optical fiber. For engineering applications of OTDR, it is important to know the repeatable limits of its performance. The author constructed an OTDR-based, submillimeter resolution strain measurement system from off-the-shelf components. The systems repeatably resolves changes in time of flight to within {plus_minus}2 ps. Using a 1-m, single-mode fiber as a gauge and observing the time of flight between Fresnel reflections, a repeatable sensitivity of 400 microstrains was observed. Using the same fiber to connect the legs of a 3-dB directional coupler to form a loop, a repeatable sensitivity of 200 microstrains was observed. Realizable changes to the system that should improve the repeatable sensitivity to 20 microstrains or less are discussed.
Coulomb gauge Gribov copies and the confining potential
Tom Heinzl; Kurt Langfeld; Martin Lavelle; David McMullan
2007-09-05T23:59:59.000Z
We study the approach, initiated by Marinari et al., to the static inter-quark potential based on Polyakov lines of finite temporal extent, evaluated in Coulomb gauge. We show that, at small spatial separations, the potential can be understood as being between two separately gauge invariant colour charges. At larger separations Gribov copies obstruct the non-perturbative identification of individually gauge invariant colour states. We demonstrate, for the first time, how gauge invariance can be maintained quite generally by averaging over Gribov copies. This allows us to extend the analysis of the Polyakov lines and the corresponding, gauge invariant quark-antiquark state to all distance scales. Using large scale lattice simulations, we show that this interpolating state possesses a good overlap with the ground state in the quark-antiquark sector and yields the full static inter-quark potential at all distances. A visual representation of the Gribov copies on the lattice is also presented.
Gauging the Relativistic Particle Model on the Noncommutative plane
Nejad, Salman Abarghouei; Monemzadeh, Majid
2015-01-01T23:59:59.000Z
We construct a new model for relativistic particle on the noncommutative surface in $(2+1)$ dimensions, using the symplectic formalism of constrained systems and embedding the model on an extended phase space. We suggest a short cut to construct the gauged Lagrangian, using the Poisson algebra of constraints, without calculating the whole procedure of symplectic formalism. We also propose an approach for the systems, in which the symplectic formalism is not applicable, due to truncation of secondary constraints appearing at the first level. After gauging the model, we obtained generators of gauge transformations of the model. Finally, by extracting the corresponding Poisson structure of all constraints, we show the effect of gauging on the canonical structure of the phase spaces of both primary and gauged models.
Noncommutative Gauge Field Theories: A No-Go Theorem
M. Chaichian; P. Prešnajder; M. M. Sheikh-Jabbari; A. Tureanu
2001-07-05T23:59:59.000Z
Studying the general structure of the noncommutative (NC) local groups, we prove a no-go theorem for NC gauge theories. According to this theorem, the closure condition of the gauge algebra implies that: 1) the local NC $u(n)$ {\\it algebra} only admits the irreducible n by n matrix-representation. Hence the gauge fields are in n by n matrix form, while the matter fields {\\it can only be} in fundamental, adjoint or singlet states; 2) for any gauge group consisting of several simple-group factors, the matter fields can transform nontrivially under {\\it at most two} NC group factors. In other words, the matter fields cannot carry more than two NC gauge group charges. This no-go theorem imposes strong restrictions on the NC version of the Standard Model and in resolving the standing problem of charge quantization in noncommutative QED.
Formulation of quantum mechanics in terms of gauge transformations
S. R. Vatsya
2014-05-29T23:59:59.000Z
Formulations of quantum mechanics incorporating the Weyl gauge transformations are studied in this article and developed further. In the process, impact of the method of observation on its outcome is interpreted in terms of the assigned gauges by incorporating properties of the corresponding experimental arrangement in defining them. Further, the assigned gauge is explicitly incorporated in the Feynman path integral formulation of quantum mechanics. The resulting wavefunction, which is not uniquely defined, represents a gauge equivalence class. The representative wavefunction is still obtained by the original path integral method. Methods to obtain the pertinent information about the assigned gauges supplementing the representative wavefunction are discussed. The probability density is shown to be a uniquely defined gauge invariant quantity but at the expense of some information describing the observable effects contained in gauge factors. In the standard quantum mechanics, a wavefunction is assumed to be defined within a phase factor while the probability density is phase-independent, paralleling these results. Also, the path integral method is used to deduce the Klein-Gordon equation for the representative wavefunction in the Riemannian spaces in a more streamlined manner than the previous derivations.
Current and Future Carbon Budgets of Tropical Rain Forest: A Cross Scale Analysis. Final Report
Oberbauer, S. F.
2004-01-16T23:59:59.000Z
The goal of this project was to make a first assessment of the major carbon stocks and fluxes and their climatic determinants in a lowland neotropical rain forest, the La Selva Biological Station, Costa Rica. Our research design was based on the concurrent use of several of the best available approaches, so that data could be cross-validated. A major focus of our effort was to combine meteorological studies of whole-forest carbon exchange (eddy flux), with parallel independent measurements of key components of the forest carbon budget. The eddy flux system operated from February 1998 to February 2001. To obtain field data that could be scaled up to the landscape level, we monitored carbon stocks, net primary productivity components including tree growth and mortality, litterfall, woody debris production, root biomass, and soil respiration in a series of replicated plots stratified across the major environmental gradients of the forest. A second major focus of this project was on the stocks and changes of carbon in the soil. We used isotope studies and intensive monitoring to investigate soil organic stocks and the climate-driven variation of soil respiration down the soil profile, in a set of six 4m deep soil shafts stratified across the landscape. We measured short term tree growth, climate responses of sap flow, and phenology in a suite of ten canopy trees to develop individual models of tree growth to daytime weather variables.
Acid rain regs will be falling on utilities in '84, but not too hard
Smock, R.
1984-01-01T23:59:59.000Z
Regulations will probably call for sulfur dioxide scrubber retrofits on some older power plants in 1984, but because the action will likely be administrative under the Clean Air Act rather than new legislation, the rulings will be less harsh. A response to Canadian pressures was delayed when administration attention focused on military problems and rejected the first Environmental Protection Agency (EPA) proposals submitted by the new director as too costly. Failure to take action in 1984, however, will be politically damaging to the administration during an election year. A lack of scientific data hampers decision making, but EPA scientists predict there will be enough information by 1988 to accurately quantify acid-rain damage. EPA must decide which states to include in the regulations, how much to reduce sulfur dioxide emissions, and how to allocate quotas. Complicating the issue is the effect on the jobs of high-sulfur coal miners and the high capital costs of scrubbers. A low-cost retrofit may be possible with a furnace-injection technique now under study. 2 figures, 3 tables. (DCK)
Survival and distribution of Vibrio cholerae in a tropical rain forest stream
Perez-Rosas, N. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico). Microbial Ecology Lab.; Hazen, T.C. [E.I. DuPont de Nemours and Co., Aiken, SC (United States). Savannah River Lab.
1988-12-31T23:59:59.000Z
For 12 months Vibrio cholerae and fecal coliforms were monitored along with 9 other water quality parameters at 12 sites in a rain forest watershed in Puerto Rico. Densities of V. cholerae and fecal coliforms were not significantly correlated even though the highest densities of both bacteria were found at a sewage outfall. High densities of V. cholerae were also found at pristine sites high in the watershed. V. cholerae and Escherichia coli were inoculated into membrane diffusion chambers, placed at two sites and monitored for 5 days on two different occasions. Two different direct count methods indicated that the density of E. coli and V. cholerae did not change significantly during the course of either study. Physiological activity, as measured by INT-reduction and relative nucleic acid composition declined for E. coli during the first 12 h then increased and remained variable during the remainder of the study. V. cholerae activity, as measured by relative nucleic acid concentrations, remained high and unchanged for the entire study. INT-reduction in V. cholerae declined initially but regained nearly all of it`s original activity within 48 h. This study suggests that V. cholerae is an indigenous organism in tropical freshwaters and that assays other than fecal coliforms or E. coli must be used for assessing public health risk in tropical waters.
Varble, Adam; Zipser, Edward J.; Fridlind, Ann; Zhu, Ping; Ackerman, Andrew; Chaboureau, Jean-Pierre; Fan, Jiwen; Hill, Adrian; Shipway, Ben; Williams, Christopher R.
2014-12-27T23:59:59.000Z
Ten 3D cloud-resolving model (CRM) simulations and four 3D limited area model (LAM) simulations of an intense mesoscale convective system observed on January 23-24, 2006 during the Tropical Warm Pool – International Cloud Experiment (TWP-ICE) are compared with each other and with observations and retrievals from a scanning polarimetric radar, co-located UHF and VHF vertical profilers, and a Joss-Waldvogel disdrometer in an attempt to explain published results showing a low bias in simulated stratiform rainfall. Despite different forcing methodologies, similar precipitation microphysics errors appear in CRMs and LAMs with differences that depend on the details of the bulk microphysics scheme used. One-moment schemes produce too many small raindrops, which biases Doppler velocities low, but produces rain water contents (RWCs) that are similar to observed. Two-moment rain schemes with a gamma shape parameter (?) of 0 produce excessive size sorting, which leads to larger Doppler velocities than those produced in one-moment schemes, but lower RWCs than observed. Two moment schemes also produce a convective median volume diameter distribution that is too broad relative to observations and thus, may have issues balancing raindrop formation, collision coalescence, and raindrop breakup. Assuming a ? of 2.5 rather than 0 for the raindrop size distribution improves one-moment scheme biases, and allowing ? to have values greater than 0 may improve two-moment schemes. Under-predicted stratiform rain rates are associated with under-predicted ice water contents at the melting level rather than excessive rain evaporation, in turn likely associated with convective detrainment that is too high in the troposphere and mesoscale circulations that are too weak. In addition to stronger convective updrafts than observed, limited domain size prevents a large, well-developed stratiform region from developing in CRMs, while a dry bias in ECMWF analyses does the same to the LAMs.
Quantized gauge-affine gravity in the superfiber bundle approach
A. Meziane; M. Tahiri
2005-11-10T23:59:59.000Z
The quantization of gauge-affine gravity within the superfiber bundle formalism is proposed. By introducing an even pseudotensorial 1-superform over a principal superfibre bundle with superconnection, we obtain the geometrical Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST transformations of the fields occurring in such a theory. Reducing the four-dimensional general affine group double-covering to the Poincare group double-covering we also find the BRST and anti-BRST transformations of the fields present in Einstein's gravity. Furthermore, we give a prescription leading to the construction of both BRST-invariant gauge-fixing action for gauge-affine gravity and Einstein's gravity.
Gauge Symmetry and Supersymmetry of Multiple M2-Branes
Jonathan Bagger; Neil Lambert
2007-12-20T23:59:59.000Z
In previous work we proposed a field theory model for multiple M2-branes based on an algebra with a totally antisymmetric triple product. In this paper we gauge a symmetry that arises from the algebra's triple product. We then construct a supersymmetric theory that is consistent with all the symmetries expected of a multiple M2-brane theory: 16 supersymmetries, conformal invariance, and an SO(8) R-symmetry that acts on the eight transverse scalars. The gauge field is not dynamical. The result is a new type of maximally supersymmetric gauge theory in three dimensions.
Non-Abelian Lattice Gauge Theories in Superconducting Circuits
Mezzacapo, A; Sabín, C; Egusquiza, I L; Lamata, L; Solano, E
2015-01-01T23:59:59.000Z
We propose a digital quantum simulator of non-Abelian pure-gauge models with a superconducting circuit setup. Within the framework of quantum link models, we build a minimal instance of a pure $SU(2)$ gauge theory, using triangular plaquettes involving geometric frustration. This realization is the least demanding, in terms of quantum simulation resources, of a non-Abelian gauge dynamics. We present two superconducting architectures that can host the quantum simulation, estimating the requirements needed to run possible experiments. The proposal establishes a path to the experimental simulation of non-Abelian physics with solid-state quantum platforms.
Is SU(2) lattice gauge theory a spin glass?
Michael Grady
2010-03-26T23:59:59.000Z
A new order parameter is constructed for SU(2) lattice gauge theory in the context of the two-real-replica method normally used for spin glasses. The order parameter is sensitive to a global Z2 subgroup of the gauge symmetry which is seen to break spontaneously at $\\beta = 4/g^2 = 1.96\\pm 0.01$. No gauge fixing is required. Finite size scaling is consistent with a high-order paramagnet to spin glass transition with a critical exponent $\
Non-Abelian Lattice Gauge Theories in Superconducting Circuits
A. Mezzacapo; E. Rico; C. Sabín; I. L. Egusquiza; L. Lamata; E. Solano
2015-05-18T23:59:59.000Z
We propose a digital quantum simulator of non-Abelian pure-gauge models with a superconducting circuit setup. Within the framework of quantum link models, we build a minimal instance of a pure $SU(2)$ gauge theory, using triangular plaquettes involving geometric frustration. This realization is the least demanding, in terms of quantum simulation resources, of a non-Abelian gauge dynamics. We present two superconducting architectures that can host the quantum simulation, estimating the requirements needed to run possible experiments. The proposal establishes a path to the experimental simulation of non-Abelian physics with solid-state quantum platforms.
Simulating plasma instabilities in SU(3) gauge theory
J. Berges; D. Gelfand; S. Scheffler; D. Sexty
2009-05-04T23:59:59.000Z
We compute nonequilibrium dynamics of plasma instabilities in classical-statistical lattice gauge theory in 3+1 dimensions. The simulations are done for the first time for the SU(3) gauge group relevant for quantum chromodynamics. We find a qualitatively similar behavior as compared to earlier investigations in SU(2) gauge theory. The characteristic growth rates are about 25 % lower for given energy density, such that the isotropization process is slower. Measured in units of the characteristic screening mass, the primary growth rate is independent of the number of colors.
On the defect induced gauge and Yukawa fields in graphene
Corneliu Sochichiu
2011-03-08T23:59:59.000Z
We consider lattice deformations (both continuous and topological) in the hexagonal lattice Hubbard model in the tight binding approximation to graphene, involving operators with the range up to next-to-neighbor. In the low energy limit, we find that these deformations give rise to couplings of the electronic Dirac field to an external scalar (Yukawa) and gauge fields. The fields are expressed in terms of original defects. As a by-product we establish that the next-to-nearest order is the minimal range of deformations which produces the complete gauge and scalar fields. We consider an example of Stone--Wales defect, and find the associated gauge field.
Pure SU(3) lattice gauge theory using operators and states
J. B. Bronzan
2006-10-13T23:59:59.000Z
We study pure SU(3) gauge theory on a large lattice, using Schrodinger's equation. Our approximate solution uses a basis of roughly 1000 states. Gauge invariance is recovered when the color content of the ground state is extrapolated to zero. We are able to identify the gauge invariant excitations that remain when the extrapolation is performed. In the weak coupling limit, we obtain promising results when we compare the excitation energies (masses) to known results, which we derive. We discuss the application of our nonperturbative method to the regime where glueballs are present.
Petroski, Thomas John
2000-01-01T23:59:59.000Z
observing stations, are a particular challenge for numerical models. A meteorological overview of this event is presented along with a comparison to the Maddox et al. (1979) heavy rain conceptual model. This event was fairly consistent with the conceptual...
White, Lee JT
An investigation of the effects of commercial mechanised selective logging on rain forest vegetation and mammals, was undertaken in the Lope Reserve, central Gabon, between January 1989 to July 1991. Vegetation in Lope ...
Niyogi, Dev
The role of land surface processes on the mesoscale simulation of the July 26, 2005 heavy rain Mesoscale convection Weather research and forecast model Indian summer monsoon Land surface processes
Lepton Flavor Violation in Flavored Gauge Mediation
Lorenzo Calibbi; Paride Paradisi; Robert Ziegler
2014-08-04T23:59:59.000Z
We study the anatomy and phenomenology of Lepton Flavor Violation (LFV) in the context of Flavored Gauge Mediation (FGM). Within FGM, the messenger sector couples directly to the MSSM matter fields with couplings controlled by the same dynamics that explains the hierarchies in the SM Yukawas. Although the pattern of flavor violation depends on the particular underlying flavor model, FGM provides a built-in flavor suppression similar to wave function renormalization or SUSY Partial Compositeness. Moreover, in contrast to these models, there is an additional suppression of left-right (LR) flavor transitions by third-generation Yukawas that in particular provides an extra protection against flavor-blind phases. We exploit the consequences of this setup for lepton flavor phenomenology, assuming that the new couplings are controlled by simple U(1) flavor models that have been proposed to accommodate large neutrino mixing angles. Remarkably, it turns out that in the context of FGM these models can pass the impressive constraints from LFV processes and leptonic EDMs even for light superpartners, therefore offering the possibility of resolving the longstanding muon g-2 anomaly.
Particlelike solutions to classical noncommutative gauge theory
Stern, A. [Department of Physics, University of Alabama, Tuscaloosa, Alabama 35487 (United States)
2008-09-15T23:59:59.000Z
We construct perturbative static solutions to the classical field equations of noncommutative U(1) gauge theory for the three cases: (a) space-time noncommutativity, (b) space-space noncommutativity, and (c) both (a) and (b). The solutions tend to the Coulomb solution at spatial infinity and are valid for intermediate values of the radial coordinate r. They yield a self-charge inside a sphere of radius r centered about the origin which increases with decreasing r for case (a), and decreases with decreasing r for case (b). For case (a) this may mean that the exact solution screens an infinite charge at the origin, while for case (b) it is plausible that the charge density is well behaved at the origin, as happens in Born-Infeld electrodynamics. For both cases (a) and (b) the self-energy in the intermediate region grows faster as r tends to the origin than that of the Coulomb solution. It then appears that the divergence of the classical self-energy is more severe in the noncommutative theory than it is in the corresponding commutative theory. We compute the lowest order effects of these solutions on the hydrogen atom spectrum and use them to put experimental bounds on the space-time and space-space noncommutative scales. For the former we get a significant improvement over previous bounds. We find that cases (a) and (b) have different experimental signatures.
National Computational Infrastructure for Lattice Gauge Theory
Reed, Daniel, A
2008-05-30T23:59:59.000Z
In this document we describe work done under the SciDAC-1 Project National Computerational Infrastructure for Lattice Gauge Theory. The objective of this project was to construct the computational infrastructure needed to study quantim chromodynamics (QCD). Nearly all high energy and nuclear physicists in the United States working on the numerical study of QCD are involved in the project, as are Brookhaven National Laboratory (BNL), Fermi National Accelerator Laboratory (FNAL), and Thomas Jefferson National Accelerator Facility (JLab). A list of the serior participants is given in Appendix A.2. The project includes the development of community software for the effective use of the terascale computers, and the research and development of commodity clusters optimized for the study of QCD. The software developed as part of this effort is pubicly available, and is being widely used by physicists in the United States and abroad. The prototype clusters built with SciDAC-1 fund have been used to test the software, and are available to lattice guage theorists in the United States on a peer reviewed basis.
Local gauge theory and coarse graining
Jose A. Zapata
2012-03-11T23:59:59.000Z
Within the discrete gauge theory which is the basis of spin foam models, the problem of macroscopically faithful coarse graining is studied. Macroscopic data is identified; it contains the holonomy evaluation along a discrete set of loops and the homotopy classes of certain maps. When two configurations share this data they are related by a local deformation. The interpretation is that such configurations differ by "microscopic details". In many cases the homotopy type of the relevant maps is trivial for every connection; two important cases in which the homotopy data is composed by a set of integer numbers are: (i) a two dimensional base manifold and structure group U(1), (ii) a four dimensional base manifold and structure group SU(2). These cases are relevant for spin foam models of two dimensional gravity and four dimensional gravity respectively. This result suggests that if spin foam models for two-dimensional and four-dimensional gravity are modified to include all the relevant macroscopic degrees of freedom -the complete collection of macroscopic variables necessary to ensure faithful coarse graining-, then they could provide appropriate effective theories at a given scale.
Rosenfeld, Daniel; Chemke, Rei; DeMott, Paul J.; Sullivan, Ryan C.; Rasmussen, R M.; McDonough, Frank; Comstock, Jennifer M.; Schmid, Beat; Tomlinson, Jason M.; Jonsson, Haf; Suski, Kaitlyn; Cazorla, Alberto; Prather, Kimberly
2013-09-05T23:59:59.000Z
The formation of highly supercooled rain was documented by aircraft observations in clouds at a wide range of conditions near the coastal region of the western United States. Several case studies are described in detail using combined cloud and aerosol measurements to document both the highly super-cooled condition and the relatively pristine aerosol conditions under which it forms. The case studies include: (1) Marine convective clouds over the coastal waters of northern California, as measured by cloud physics probes flown on a Gulfstream-1 aircraft during the CALWATER campaign in February and early March 2011. The clouds had extensive drizzle in their tops, which extended downward to the 0°C isotherm as supercooled rain. Ice multiplication was observed only in mature parts of the clouds where cloud water was already depleted. (2) Orographically triggered convective clouds in marine air mass over the foothills of the Sierra Nevada to the east of Sacramento, as measured in CALWATER. Supercooled rain was observed down to -21°C. No indications for ice multiplication were evident. (3) Orographic layer clouds over Yosemite National Park, also measured in CALWATER. The clouds had extensive drizzle at -21°C, which intensified with little freezing lower in the cloud, and (4) Supercooled drizzle drops in layer clouds near Juneau, Alaska, as measured by the Wyoming King Air as part of a FAA project to study aircraft icing in this region. Low concentrations of CCN was a common observation in all these clouds, allowing for the formation of clouds with small concentration of large drops that coalesced into supercooled drizzle and raindrops. Another common observation was the absence of ice nuclei and/or ice crystals in measurable concentrations was associated with the persistent supercooled drizzle and rain. Average ice crystal concentrations were 0.007 l-1 at the top of convective clouds at -12°C and 0.03 l-1 in the case of layer clouds at -21°C. In combination these two conditions provide ideal conditions for the formation of highly supercooled drizzle and rain. These results help explain the anomalously high incidences of aircraft icing at cold temperatures in U.S. west coast clouds (Bernstein et al., 2004) and highlight the need to include aerosol effects when simulating aircraft icing with cloud models. These case studies can also serve as benchmarks for explicit cloud microphysics models attempting to simulate the formation of precipitation in these types of pristine conditions.
The gauge algebra of double field theory and Courant brackets
Hull, Chris
We investigate the symmetry algebra of the recently proposed field theory on a doubled torus that describes closed string modes on a torus with both momentum and winding. The gauge parameters are constrained fields on the ...
Manifestly gauge-covariant representation of scalar and fermion propagators
Latosi?ski, Adam
2015-01-01T23:59:59.000Z
A new way to write the massive scalar and fermion propagators on a background of a weak gauge field is presented. They are written in a form that is manifestly gauge-covariant up to several additional terms that can be written as boundary terms in momentum space. These additional terms violate Ward-Takahashi identities and need to be renormalized by appropriate counterterms if the complete theory is to be gauge-covariant. This form makes it possible to calculate many amplitudes in a manifestly gauge-covariant way (at the same time reducing the number of Feynman diagrams). It also allows to express some counterterms in a way independent of the regularization scheme and provides an easy way to derive the anomalous term affecting the chiral current conservation.
Gauge-invariant Green function dynamics: A unified approach
Swiecicki, Sylvia D., E-mail: sswiecic@physics.utoronto.ca; Sipe, J.E., E-mail: sipe@physics.utoronto.ca
2013-11-15T23:59:59.000Z
We present a gauge-invariant description of Green function dynamics introduced by means of a generalized Peirels phase involving an arbitrary differentiable path in space–time. Two other approaches to formulating a gauge-invariant description of systems, the Green function treatment of Levanda and Fleurov [M. Levanda, V. Fleurov, J. Phys.: Condens. Matter 6 (1994) 7889] and the usual multipolar expansion for an atom, are shown to arise as special cases of our formalism. We argue that the consideration of paths in the generalized Peirels phase that do not lead to introduction of an effective gauge-invariant Hamiltonian with polarization and magnetization fields may prove useful for the treatment of the response of materials with short electron correlation lengths. -- Highlights: •Peirels phase for an arbitrary path in space–time established. •Gauge-invariant Green functions and the Power–Zienau–Wooley transformation connected. •Limitations on possible polarization and magnetization fields established.
The Higgs boson as a gauge field in extra dimensions
Marco Serone
2005-08-29T23:59:59.000Z
I review, at a general non-technical level, the main properties of models in extra dimensions where the Higgs field is identified with some internal component of a gauge field.
A gauge invariant cluster algorithm for the Ising spin glass
K. Langfeld; M. Quandt; W. Lutz; H. Reinhardt
2006-06-14T23:59:59.000Z
The frustrated Ising model in two dimensions is revisited. The frustration is quantified in terms of the number of non-trivial plaquettes which is invariant under the Nishimori gauge symmetry. The exact ground state energy is calculated using Edmond's algorithm. A novel cluster algorithm is designed which treats gauge equivalent spin glasses on equal footing and allows for efficient simulations near criticality. As a first application, the specific heat near criticality is investigated.
Cancellation of energy-divergences in Coulomb gauge QCD
A. Andraši; J. C. Taylor
2005-04-18T23:59:59.000Z
In the Coulomb gauge of nonabelian gauge theories there are in general, in individual graphs, 'energy-divergences' on integrating over the loop energy variable for fixed loop momentum. These divergences are avoided in the Hamiltonian, phase-space formulation. But, even in this formulation, energy-divergences re-appear at 2-loop order. We show in an example how these cancel between graphs as a consequence of Ward identities.
Stability, creation and annihilation of charges in gauge theories
Ilderton, Anton [School of Mathematics, Trinity College, Dublin 2 (Ireland)], E-mail: antoni@maths.tcd.ie; Lavelle, Martin [School of Computing and Mathematics, University of Plymouth, Plymouth PL48AA (United Kingdom)], E-mail: martin.lavelle@plymouth.ac.uk; McMullan, David [School of Computing and Mathematics, University of Plymouth, Plymouth PL48AA (United Kingdom)], E-mail: david.mcmullan@plymouth.ac.uk
2010-04-15T23:59:59.000Z
We show how to construct physical, minimal energy states for systems of static and moving charges. These states are manifestly gauge invariant. For charge-anticharge systems we also construct states in which the gauge fields are restricted to a finite volume around the location of the matter fields. Although this is an excited state, it is not singular, unlike all previous finite volume descriptions. We use our states to model the processes of pair creation and annihilation.
Noncommutative SU(N) gauge theory and asymptotic freedom
Latas, D.; Radovanovic, V. [Faculty of Physics, University of Belgrade, P.O. Box 368, 11001 Belgrade (Serbia); Trampetic, J. [Theoretical Physics Division, Rudjer Boskovic Institute, Zagreb (Croatia)
2007-10-15T23:59:59.000Z
In this paper we analyze a version of the SU(N) gauge theory on noncommutative space-time which is one-loop renormalizable to first order in the expansion in the noncommutativity parameter {theta}. The one-loop renormalizability is obtained through the modification of the initial 'minimal' action, with the gauge fields in the adjoint representation of SU(N), and by the renormalization of the noncommutativity parameter {theta}.
Noncommuting Electric Fields and Algebraic Consistency in Noncommutative Gauge theories
Rabin Banerjee
2003-03-20T23:59:59.000Z
We show that noncommuting electric fields occur naturally in $\\theta$-expanded noncommutative gauge theories. Using this noncommutativity, which is field dependent, and a hamiltonian generalisation of the Seiberg-Witten Map, the algebraic consistency in the lagrangian and hamiltonian formulations of these theories, is established. A comparison of results in different descriptions shows that this generalised map acts as canonical transformation in the physical subspace only. Finally, we apply the hamiltonian formulation to derive the gauge symmetries of the action.
A Maxwell's equations, Coulomb gauge analysis of two scatterers
Crowell, Kelly Jean
1990-01-01T23:59:59.000Z
A MAXWELL'S EQUATIONS, COULOMB GAUGE ANALYSIS OF TWO SCATTERERS A Thesis by KELLY JEAN CROWELL Submitted to the Office of Graduate Studies of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... May 1990 Major Subject: Electrical Engineering A MAXWELL'S EQUATIONS, COULOMB GAUGE ANALYSIS OF TWO SCATTERERS A Thesis by KELLY JEAN CROWELL Approved as to style and content by: Robert D. Nevels (Chairman of Committee) D. R. Halverson...
Load cell having strain gauges of arbitrary location
Spletzer, Barry (Albuquerque, NM)
2007-03-13T23:59:59.000Z
A load cell utilizes a plurality of strain gauges mounted upon the load cell body such that there are six independent load-strain relations. Load is determined by applying the inverse of a load-strain sensitivity matrix to a measured strain vector. The sensitivity matrix is determined by performing a multivariate regression technique on a set of known loads correlated to the resulting strains. Temperature compensation is achieved by configuring the strain gauges as co-located orthogonal pairs.
Peter Arnold; Diana Vaman
2010-10-25T23:59:59.000Z
Previous studies of high-energy jet stopping in strongly-coupled plasmas have lacked a clear gauge-theory specification of the initial state. We show how to set up a well-defined gauge theory problem to study jet stopping in pure {\\cal N}=4 super Yang Mills theory (somewhat analogous to Hofman and Maldacena's studies at zero temperature) and solve it by using gauge-gravity duality for real-time, finite-temperature 3-point correlators. Previous studies have found that the stopping distance scales with energy as E^{1/3} (with disagreement on the gauge coupling dependence). We do find that none of the jet survives beyond this scale, but we find that almost all of our jet stops at a parametrically smaller scale proportional to (E L)^{1/4}, where L is the size of the space-time region where the jet is initially created.
Low-energy U(1) x USp(2M) gauge theory from simple high-energy gauge group
Sven Bjarke Gudnason; Kenichi Konishi
2010-05-17T23:59:59.000Z
We give an explicit example of the embedding of a near BPS low-energy (U(1) x USp(2M))/Z_2 gauge theory into a high-energy theory with a simple gauge group and adjoint matter content. This system possesses degenerate monopoles arising from the high-energy symmetry breaking as well as non-Abelian vortices due to the symmetry breaking at low energies. These solitons of different codimensions are related by the exact homotopy sequences.
A new look at the problem of gauge invariance in quantum field theory
Dan Solomon
2007-06-19T23:59:59.000Z
Quantum field theory is assumed to be gauge invariant. However it is well known that when certain quantities are calculated using perturbation theory the results are not gauge invariant. The non-gauge invariant terms have to be removed in order to obtain a physically correct result. In this paper we will examine this problem and determine why a theory that is supposed to be gauge invariant produces non-gauge invariant results.
Gauge turbulence, topological defect dynamics, and condensation in Higgs models
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Gasenzer, Thomas [Universitat Heidelberg, Institut fur Theoretische Physik, Heidelberg (Germany); GSI, ExtreMe Matter Institute EMMI, Darmstadt (Germany); McLerran, Larry [Brookhaven National Laboratory, Physics Department, RIKEN BNL Research Center Upton NY (United States); China Central Normal University, Physics Department, Wuhan (China); Pawlowski, Jan M [Universitat Heidelberg, Institut fur Theoretische Physik, Heidelberg (Germany); GSI, ExtreMe Matter Institute EMMI, Darmstadt (Germany); Sexty, Denes [Universitat Heidelberg, Institut fur Theoretische Physik, Heidelberg (Germany); GSI, ExtreMe Matter Institute EMMI, Darmstadt (Germany)
2014-10-01T23:59:59.000Z
The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appearing in the gauge field are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixed point of the far-from-equilibrium dynamical evolution, signaled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of Yang–Mills fields and potential mechanisms of how confinement and condensation in non-Abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.
Noncommutative gauge theory and symmetry breaking in matrix models
Grosse, Harald; Steinacker, Harold [Department of Physics, University of Vienna, Boltzmanngasse5, A-1090 Vienna (Austria); Lizzi, Fedele [Dipartimento di Scienze Fisiche, Universita di Napoli Federico II and INFN, Sezione di Napoli, Via Cintia, 80126 Napoli (Italy); High Energy Physics Group, Departament d'Estructura i Constituents de la Materia and Institut de Ciencies del Cosmos Universitat de Barcelona Barcelona, Catalonia (Spain)
2010-04-15T23:59:59.000Z
We show how the fields and particles of the standard model can be naturally realized in noncommutative gauge theory. Starting with a Yang-Mills matrix model in more than four dimensions, an SU(n) gauge theory on a Moyal-Weyl space arises with all matter and fields in the adjoint of the gauge group. We show how this gauge symmetry can be broken spontaneously down to SU(3){sub c}xSU(2){sub L}xU(1){sub Q}[resp. SU(3){sub c}xU(1){sub Q}], which couples appropriately to all fields in the standard model. An additional U(1){sub B} gauge group arises which is anomalous at low energies, while the trace-U(1) sector is understood in terms of emergent gravity. A number of additional fields arise, which we assume to be massive, in a pattern that is reminiscent of supersymmetry. The symmetry breaking might arise via spontaneously generated fuzzy spheres, in which case the mechanism is similar to brane constructions in string theory.
Gauge turbulence, topological defect dynamics, and condensation in Higgs models
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Gasenzer, Thomas; McLerran, Larry; Pawlowski, Jan M.; Sexty, Dénes
2014-10-01T23:59:59.000Z
The real-time dynamics of topological defects and turbulent configurations of gauge fields for electric and magnetic confinement are studied numerically within a 2+1D Abelian Higgs model. It is shown that confinement is appearing in such systems equilibrating after a strong initial quench such as the overpopulation of the infrared modes. While the final equilibrium state does not support confinement, metastable vortex defect configurations appearing in the gauge field are found to be closely related to the appearance of physically observable confined electric and magnetic charges. These phenomena are seen to be intimately related to the approach of a non-thermal fixedmore »point of the far-from-equilibrium dynamical evolution, signaled by universal scaling in the gauge-invariant correlation function of the Higgs field. Even when the parameters of the Higgs action do not support condensate formation in the vacuum, during this approach, transient Higgs condensation is observed. We discuss implications of these results for the far-from-equilibrium dynamics of Yang–Mills fields and potential mechanisms of how confinement and condensation in non-Abelian gauge fields can be understood in terms of the dynamics of Higgs models. These suggest that there is an interesting new class of dynamics of strong coherent turbulent gauge fields with condensates.« less
Geometrical Hyperbolic Systems for General Relativity and Gauge Theories
A. Abrahams; A. Anderson; Y. Choquet-Bruhat; J. W. York Jr
1996-05-08T23:59:59.000Z
The evolution equations of Einstein's theory and of Maxwell's theory---the latter used as a simple model to illustrate the former--- are written in gauge covariant first order symmetric hyperbolic form with only physically natural characteristic directions and speeds for the dynamical variables. Quantities representing gauge degrees of freedom [the spatial shift vector $\\beta^{i}(t,x^{j})$ and the spatial scalar potential $\\phi(t,x^{j})$, respectively] are not among the dynamical variables: the gauge and the physical quantities in the evolution equations are effectively decoupled. For example, the gauge quantities could be obtained as functions of $(t,x^{j})$ from subsidiary equations that are not part of the evolution equations. Propagation of certain (``radiative'') dynamical variables along the physical light cone is gauge invariant while the remaining dynamical variables are dragged along the axes orthogonal to the spacelike time slices by the propagating variables. We obtain these results by $(1)$ taking a further time derivative of the equation of motion of the canonical momentum, and $(2)$ adding a covariant spatial derivative of the momentum constraints of general relativity (Lagrange multiplier $\\beta^{i}$) or of the Gauss's law constraint of electromagnetism (Lagrange multiplier $\\phi$). General relativity also requires a harmonic time slicing condition or a specific generalization of it that brings in the Hamiltonian constraint when we pass to first order symmetric form. The dynamically propagating gravity fields straightforwardly determine the ``electric'' or ``tidal'' parts of the Riemann tensor.
Gauge/Gravity Theory with Running Dilaton and Running Axion
Girma Hailu
2007-12-27T23:59:59.000Z
We present a new gauge/gravity duality construction of the Klebanov-Strassler throat which takes corrections to the anomalous mass dimension proposed in [1] into account on the gauge theory side and both the dilaton and the axion run on the gravity side. The corresponding supergravity solutions are found using equations for type IIB flows with N=1 supersymmetry obtained in [2]. We find that magnetic couplings of the axion to D7-branes filling 4-d spacetime and wrapping 4-cycles at locations of duality transitions and invisible Dirac 8-branes whose worldvolume emanates from the worldvolume of the D7-branes are the sources for the runnings of the dilaton and the axion. Our construction provides the first explicit example of a gauge/gravity duality mapping with a running dilaton or a running axion which is an important component towards finding gravity duals to gauge theories with physically more interesting renormalization group flows such as pure confining gauge theories in four dimensions. The D7-branes also serve as gravitational source for Seiberg duality transitions. The supergravity background has distinct features which could be useful for constructing cosmological models and studying possibilities for probing stringy signatures from the early universe.
Gauge-preheating and the end of axion inflation
Adshead, Peter; Scully, Timothy R; Sfakianakis, Evangelos I
2015-01-01T23:59:59.000Z
We study the onset of the reheating epoch at the end of axion-driven inflation where the axion is coupled to an Abelian, $U(1)$, gauge field via a Chern-Simons interaction term. We focus primarily on $m^2\\phi^2$ inflation and explore the possibility that preheating can occur for a range of coupling values consistent with recent observations and bounds on the overproduction of primordial black holes. We find that for a wide range of parameters preheating is efficient. In certain cases the inflaton is seen to transfer all its energy to the gauge fields within a few oscillations. We find that the gauge fields on sub-horizon scales end in an unpolarized state, due to the existence of strong rescattering between the inflaton and gauge modes. We also present a preliminary study of an axion monodromy model coupled to $U(1)$ gauge fields, seeing a similarly efficient preheating behavior as well as indications that the coupling strength has an effect on the creation of oscillons.
Gauge Theory of the Gravitational-Electromagnetic Field
Robert D. Bock
2015-05-26T23:59:59.000Z
We develop a gauge theory of the combined gravitational-electromagnetic field by expanding the Poincar\\'e group to include clock synchronization transformations. We show that the electromagnetic field can be interpreted as a local gauge theory of the synchrony group. According to this interpretation, the electromagnetic field equations possess nonlinear terms and electromagnetic gauge transformations acquire a space-time interpretation as local synchrony transformations. The free Lagrangian for the fields leads to the usual Einstein-Maxwell field equations with additional gravitational-electromagnetic coupling terms. The connection between the electromagnetic field and the invariance properties of the Lagrangian under clock synchronization transformations provides a strong theoretical argument in favor of the thesis of the conventionality of simultaneity. This suggests that clock synchronization invariance (or equivalently, invariance under transformations of the one-way speed of light) is a fundamental invariance principle of physics.
Remote high-temperature insulatorless heat-flux gauge
Noel, Bruce W. (Espanola, NM)
1993-01-01T23:59:59.000Z
A remote optical heat-flux gauge for use in extremely high temperature environments is described. This application is possible because of the use of thermographic phosphors as the sensing media, and the omission of the need for an intervening layer of insulator between phosphor layers. The gauge has no electrical leads, but is interrogated with ultraviolet or laser light. The luminescence emitted by the two phosphor layers, which is indicative of the temperature of the layers, is collected and analyzed in order to determine the heat flux incident on the surface being investigated. The two layers of thermographic phosphor must be of different materials to assure that the spectral lines collected will be distinguishable. Spatial heat-flux measurements can be made by scanning the light across the surface of the gauge.
Matrix product states for Hamiltonian lattice gauge theories
Boye Buyens; Karel Van Acoleyen; Jutho Haegeman; Frank Verstraete
2014-10-31T23:59:59.000Z
Over the last decade tensor network states (TNS) have emerged as a powerful tool for the study of quantum many body systems. The matrix product states (MPS) are one particular case of TNS and are used for the simulation of 1+1 dimensional systems. In [1] we considered the MPS formalism for the simulation of the Hamiltonian lattice gauge formulation of 1+1 dimensional one flavor quantum electrodynamics, also known as the massive Schwinger model. We deduced the ground state and lowest lying excitations. Furthermore, we performed a full quantum real-time simulation for a quench with a uniform background electric field. In this proceeding we continue our work on the Schwinger model. We demonstrate the advantage of working with gauge invariant MPS by comparing with MPS simulations on the full Hilbert space, that includes numerous non-physical gauge variant states. Furthermore, we compute the chiral condensate and recover the predicted UV-divergent behavior.
Hall viscosity from elastic gauge fields in Dirac crystals
Cortijo, Alberto; Landsteiner, Karl; Vozmediano, María A H
2015-01-01T23:59:59.000Z
The combination of Dirac physics and elasticity has been explored at length in graphene where the so--called "elastic gauge fields" have given rise to an entire new field of research and applications: Straintronics. The fact that these elastic fields couple to fermions as the electromagnetic field, implies that many electromagnetic responses will have elastic counterparts not explored before. In this work we will first show that the presence of elastic gauge fields will be the rule rather than the exception in most of the topologically non--trivial materials in two and three dimensions. In particular we will extract the elastic gauge fields associated to the recently observed Weyl semimetals, the "three dimensional graphene". As it is known, quantum electrodynamics suffers from the chiral anomaly whose consequences have been recently explored in matter systems. We will show that, associated to the physics of the anomalies, and as a counterpart of the Hall conductivity, elastic materials will have a Hall visco...
New ways to leptogenesis with gauged B-L symmetry
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Babu, K.S.; Meng, Yanzhi; Tavartkiladze, Zurab
2009-10-01T23:59:59.000Z
We show that in supersymmetric models with gauged B-L symmetry, there is a new source for cosmological lepton asymmetry. The Higgs bosons responsible for B-L gauge symmetry breaking decay dominantly into right-handed sneutrinos N~ and N~* producing an asymmetry in N~ over N~*. This can be fully converted into ordinary lepton asymmetry in the decays of N~. In simple models with gauged B-L symmetry we show that resonant/soft leptogenesis is naturally realized. Supersymmetry guarantees quasi-degenerate scalar states, while soft breaking of SUSY provides the needed CP violation. Acceptable values of baryon asymmetry are obtained without causing serious problems with gravitinomore »abundance.« less
Remote high-temperature insulatorless heat-flux gauge
Noel, B.W.
1993-12-28T23:59:59.000Z
A remote optical heat-flux gauge for use in extremely high temperature environments is described. This application is possible because of the use of thermographic phosphors as the sensing media, and the omission of the need for an intervening layer of insulator between phosphor layers. The gauge has no electrical leads, but is interrogated with ultraviolet or laser light. The luminescence emitted by the two phosphor layers, which is indicative of the temperature of the layers, is collected and analyzed in order to determine the heat flux incident on the surface being investigated. The two layers of thermographic phosphor must be of different materials to assure that the spectral lines collected will be distinguishable. Spatial heat-flux measurements can be made by scanning the light across the surface of the gauge. 3 figures.
Highly Effective Action from Large N Gauge Fields
Hyun Seok Yang
2014-09-25T23:59:59.000Z
Recently John H. Schwarz put forward a conjecture that the world-volume action of a probe D3-brane in an AdS5 x S5 background of type IIB superstring theory can be reinterpreted as the highly effective action (HEA) of four-dimensional N=4 superconformal field theory on the Coulomb branch. We argue that the HEA can be derived from the noncommutative (NC) field theory representation of the AdS/CFT correspondence and the Seiberg-Witten (SW) map defining a spacetime field redefinition between ordinary and NC gauge fields. It is based only on the well-known facts that the master fields of large N matrices are higher-dimensional NC U(1) gauge fields and the SW map is a local coordinate transformation eliminating U(1) gauge fields known as the Darboux theorem in symplectic geometry.
A. A. Reshetnyak
2003-05-21T23:59:59.000Z
The basic theorem of the Lagrangian formulation for general superfield theory of fields (GSTF) is proved. The gauge transformations of general type (GTGT) and gauge algebra of generators of GTGT (GGTGT) as the consequences of the above theorem are studied. It is established the gauge algebra of GGTGT contains the one of generators of gauge transformations of special type (GGTST) as one's subalgebra. In the framework of Lagrangian formulation for GSTF the nontrivial superfield model generalizing the model of Quantum Electrodynamics and belonging to the class of gauge theory of general type (GThGT) with Abelian gauge algebra of GGTGT is constructed.
Janis-Newman algorithm: simplifications and gauge field transformation
Harold Erbin
2015-02-16T23:59:59.000Z
The Janis-Newman algorithm is an old but very powerful tool to generate rotating solutions from static ones through a set of complex coordinate transformations. Several solutions have been derived in this way, including solutions with gauge fields. However, the transformation of the latter was so far always postulated as an ad hoc result. In this paper we propose a generalization of the procedure, extending it to the transformation of the gauge field. We also present a simplification of the algorithm due to G. Giampieri. We illustrate our prescription on the Kerr-Newman solution.
A note on Gauge Theories Coupled to Gravity
Tom Banks; Matt Johnson; Assaf Shomer
2006-06-29T23:59:59.000Z
We analyze the bound on gauge couplings $e\\geq m/m_p$, suggested by Arkani-Hamed et.al. We show this bound can be derived from simple semi-classical considerations and holds in spacetime dimensions greater than or equal to four. Non abelian gauge symmetries seem to satisfy the bound in a trivial manner. We comment on the case of discrete symmetries and close by performing some checks for the bound in higher dimensions in the context of string theory.
Muon g-2 Anomaly and Dark Leptonic Gauge Boson
Lee, Hye-Sung [W& M
2014-11-01T23:59:59.000Z
One of the major motivations to search for a dark gauge boson of MeV-GeV scale is the long-standing muon g-2 anomaly. Because of active searches such as fixed target experiments and rare meson decays, the muon g-2 favored parameter region has been rapidly reduced. With the most recent data, it is practically excluded now in the popular dark photon model. We overview the issue and investigate a potentially alternative model based on the gauged lepton number or U(1)_L, which is under different experimental constraints.
N=2 supersymmetric gauge theories and quantum integrable systems
Yuan Luo; Meng-Chwan Tan; Junya Yagi
2014-04-01T23:59:59.000Z
We study N=2 supersymmetric gauge theories on the product of a two-sphere and a cylinder. We show that the low-energy dynamics of a BPS sector of such a theory is described by a quantum integrable system, with the Planck constant set by the inverse of the radius of the sphere. If the sphere is replaced with a hemisphere, then our system reduces to an integrable system of the type studied by Nekrasov and Shatashvili. In this case we establish a correspondence between the effective prepotential of the gauge theory and the Yang-Yang function of the integrable system.
Maps for currents and anomalies in noncommutative gauge theories
Banerjee, Rabin; Kumar, Kuldeep [S.N. Bose National Centre for Basic Sciences, JD Block, Sector 3, Salt Lake, Kolkata 700098 (India)
2005-02-15T23:59:59.000Z
We derive maps relating currents and their divergences in non-Abelian U(N) noncommutative gauge theory with the corresponding expressions in the ordinary (commutative) description. For the U(1) theory, in the slowly-varying-field approximation, these maps are also seen to connect the star-gauge-covariant anomaly in the noncommutative theory with the standard Adler-Bell-Jackiw anomaly in the commutative version. For arbitrary fields, derivative corrections to the maps are explicitly computed up to O({theta}{sup 2})
A Maxwell's equations, Coulomb gauge analysis of two scatterers
Crowell, Kelly Jean
1990-01-01T23:59:59.000Z
for Wedges (P, g 180') Page 31 36 vn LIST OF FIGURES Figure 1. 2. 3. 5. 6. 7. 8. 9 - 10. Geometry for a scatterer in the presence of a wedge of angle Po Straight wire segmentation scheme Segmentation scheme for scatterer in wedge geometry...'s method. In the Lorentz gauge this procedure is well documented[21], therefore our discussion below will exclusively describe a, method for obtaining the Coulomb gauge vector and scalar potentials. To determine A" we introduce the Green's dyadic Gz...
Preserving Local Gauge Invariance with t-Channel Regge Exchange
Haberzettl, Helmut; He, Jun
2015-01-01T23:59:59.000Z
Considering single-meson photo- and electroproduction off a baryon, it is shown how to restore local gauge invariance that was broken by replacing standard Feynman-type meson exchange in the t-channel by exchange of a Regge trajectory. This is achieved by constructing a contact current whose four-divergence cancels the gauge-invariance-violating contributions resulting from all states above the base state on the Regge trajectory. To illustrate the procedure, modifications necessary for the process $\\gamma +p \\to K^+ + \\Sigma^{*0}$ are discussed in some detail. We also provide the general expression for the contact current for an arbitrary reaction.
Gauge and Higgs Boson Masses from an Extra Dimension
Graham Moir; Peter Dziennik; Nikos Irges; Francesco Knechtli; Kyoko Yoneyama
2014-11-03T23:59:59.000Z
We present novel calculations of the mass hierarchy of the $SU(2)$ pure gauge theory on a space-time lattice with an orbifolded fifth dimension. This theory has three parameters; the gauge coupling $\\beta$, the anisotropy $\\gamma$, which is a measure of the ratio of the lattice spacing in the four dimensions to that in the fifth dimension, and the extent of the extra dimension $N_{5}$. Using a large basis of scalar and vector operators we explore in detail the spectrum along the $\\gamma = 1$ line, and for the first time we investigate the spectrum for $\\gamma \
Gauge Invariant Effective Stress-Energy Tensors for Gravitational Waves
Paul R. Anderson
1996-09-09T23:59:59.000Z
It is shown that if a generalized definition of gauge invariance is used, gauge invariant effective stress-energy tensors for gravitational waves and other gravitational perturbations can be defined in a much larger variety of circumstances than has previously been possible. In particular it is no longer necessary to average the stress-energy tensor over a region of spacetime which is larger in scale than the wavelengths of the waves and it is no longer necessary to restrict attention to high frequency gravitational waves.
Harmon, J.M.; Franklin, J.F.
1995-04-01T23:59:59.000Z
The authors compared the composition and density of the on-site vegetation, seed bank, and seed rain of three geomorphic and successional surfaces along third- and fifth- order streams on the western slope of the Cascade Range in Oregon. The on-site vegetation generally was dominated by tree species, the seed bank by herb species, and the seed rain by tree and herb species. Seed rain density generally correspond to the successional stage of the geomorphic surface and frequency of site disturbance, with the youngest and least vegetatively stable geomorphic surfaces having the highest density of trapped viable seeds. The highest density and greatest species richness of seed germinants were found on the intermediate-aged geomorphic surfaces, which had moderate levels of disturbance.
Fuzzy bags, Polyakov loop and gauge/string duality
Fen Zuo
2014-09-10T23:59:59.000Z
Confinement in SU($N$) gauge theory is due to the linear potential between colored objects. At short distances, the linear contribution could be considered as the quadratic correction to the leading Coulomb term. Recent lattice data show that such quadratic corrections also appear in the deconfined phase, in both the thermal quantities and the Polyakov loop. These contributions are studied systematically employing the gauge/string duality. "Confinement" in ${\\mathcal N}=4$ SU($N$) Super Yang-Mills (SYM) theory could be achieved kinematically when the theory is defined on a compact space manifold. In the large-$N$ limit, deconfinement of ${\\mathcal N}=4$ SYM on $\\mathbb{S}^3$ at strong coupling is dual to the Hawking-Page phase transition in the global Anti-de Sitter spacetime. Meantime, all the thermal quantities and the Polyakov loop achieve significant quadratic contributions. Similar results can also be obtained at weak coupling. However, when confinement is induced dynamically through the local dilaton field in the gravity-dilaton system, these contributions can not be generated consistently. This is in accordance with the fact that there is no dimension-2 gauge-invariant operator in the boundary gauge theory. Based on these results, we suspect that quadratic corrections, and also confinement, should be due to global or non-local effects in the bulk spacetime.
Towards a Unified Theory of Gauge and Yukawa Interactions
Roepstorff, G; Vehns, Ch.
2000-01-01T23:59:59.000Z
It is suggested to combine gauge and Yukawa interactions into one expression involving the generalized Dirac operator associated with a superconnection $D+L$, $L$ being linked to the Higgs field (one doublet). We advocate a version of the Minimal Standard Model where the Higgs field gives masses to the neutrinos and a CKM matrix to the leptons.
Towards a unified theory of gauge and Yukawa interactions
G. Roepstorff; Ch. Vehns
2001-10-12T23:59:59.000Z
It is suggested to combine gauge and Yukawa interactions into one expression involving the generalized Dirac operator associated with a superconnection $D+L$, $L$ being linked to the Higgs field (one doublet). We advocate a version of the Minimal Standard Model where the Higgs field gives masses to the neutrinos and a CKM matrix to the leptons.
A note on large gauge transformations in double field theory
Usman Naseer
2015-04-22T23:59:59.000Z
We give a detailed proof of the conjecture by Hohm and Zwiebach in double field theory. This result implies that their proposal for large gauge transformations in terms of the Jacobian matrix for coordinate transformations is, as required, equivalent to the standard exponential map associated with the generalized Lie derivative along a suitable parameter.
Force measurements in magnetic bearings using fiber optic strain gauges
Raymer, Stephen Geoffrey
2000-01-01T23:59:59.000Z
The research presented here develops a new method for measuring forces in magnetic bearings. Fiber-optic strain gauges (FOSGs) mounted to the side of the magnet poles are used to detect the small levels of strain that the metal experiences...
Generalized Chern-Simons action and maximally supersymmetric gauge theories
M. V. Movshev; A. Schwarz
2013-04-28T23:59:59.000Z
We study observables and deformations of generalized Chern-Simons action and show how to apply these results to maximally supersymmetric gauge theories. We describe a construction of large class of deformations based on some results on the cohomology of super Lie algebras proved in the Appendix.
Coulomb gauge approach for charmonium meson and hybrid radiative transitions
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Gou, Peng; Yépez-Martínez, Tochtli; Szczepaniak, Adam P
2015-01-22T23:59:59.000Z
We consider the lowest order interaction of the Foldy-Wouthuysen QED and QCD Hamiltonian in the Coulomb gauge approach, to describe radiative transitions between conventional and hybrids charmonium mesons. The results are compared to potential quark models and lattices calculations.
Finiteness of the Coulomb gauge QCD perturbative effective action
A. Andrasi; J. C. Taylor
2015-04-16T23:59:59.000Z
At 2-loop order in the Coulomb gauge, individual Feynman graphs contributing to the effective action have energy divergences. It is proved that these cancel in suitable combinations of graphs. This has previously been shown only for transverse external fields. The calculation results in a generalization of the Christ-Lee term which was inserted into the Hamiltonian.
Gauge invariance and classical dynamics of noncommutative particle theory
Gitman, D. M.; Kupriyanov, V. G. [Instituto de Fisica, Universidade de Sao Paulo, 05508-090 (Brazil)
2010-02-15T23:59:59.000Z
We consider a model of classical noncommutative particle in an external electromagnetic field. For this model, we prove the existence of generalized gauge transformations. Classical dynamics in Hamiltonian and Lagrangian form is discussed; in particular, the motion in the constant magnetic field is studied in detail.
Entanglement entropy in SU(N) gauge theory
Alexander Velytsky
2008-09-25T23:59:59.000Z
The entanglement entropy of SU(N) lattice gauge theory is studied exactly in 1+1 space-time dimensions and in Migdal-Kadanoff approximation in higher dimensional space. The existence of a non-analytical behavior reminiscent of a phase transition for a characteristic size of the entangled region is demonstrated for higher dimensional theories.
Three-loop free energy for pure gauge QCD
Arnold, P.; Zhai, C. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States))
1994-12-15T23:59:59.000Z
We compute the free energy density for pure non-Abelian gauge theory at high temperature and zero chemical potential. The three-loop result to [ital O]([ital g][sup 4]) is [ital F]=[ital d][sub [ital A
Hamilton approach to Yang-Mills theory in Coulomb gauge
Reinhardt, H; Epple, D; Feuchter, C
2007-01-01T23:59:59.000Z
The vacuum wave functional of Coulomb gauge Yang-Mills theory is determined within the variational principle and used to calculate various Green functions and observables. The results show that heavy quarks are confined by a linearly rising potential and gluons cannot propagate over large distances. The 't Hooft loop shows a perimeter law and thus also indicates confinement.
Observational constraints on gauge field production in axion inflation
Meerburg, P.D. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08540 (United States); Pajer, E., E-mail: meerburg@princeton.edu, E-mail: enrico.pajer@gmail.com [Department of Physics, Princeton University, Princeton, NJ 08544 (United States)
2013-02-01T23:59:59.000Z
Models of axion inflation are particularly interesting since they provide a natural justification for the flatness of the potential over a super-Planckian distance, namely the approximate shift-symmetry of the inflaton. In addition, most of the observational consequences are directly related to this symmetry and hence are correlated. Large tensor modes can be accompanied by the observable effects of a the shift-symmetric coupling ?F F-tilde to a gauge field. During inflation this coupling leads to a copious production of gauge quanta and consequently a very distinct modification of the primordial curvature perturbations. In this work we compare these predictions with observations. We find that the leading constraint on the model comes from the CMB power spectrum when considering both WMAP 7-year and ACT data. The bispectrum generated by the non-Gaussian inverse-decay of the gauge field leads to a comparable but slightly weaker constraint. There is also a constraint from ?-distortion using TRIS plus COBE/FIRAS data, but it is much weaker. Finally we comment on a generalization of the model to massive gauge fields. When the mass is generated by some light Higgs field, observably large local non-Gaussianity can be produced.
Gauge cooling in complex Langevin for QCD with heavy quarks
Erhard Seiler; Dénes Sexty; Ion-Olimpiu Stamatescu
2012-11-20T23:59:59.000Z
We employ a new method, "gauge cooling", to stabilize complex Langevin simulations of QCD with heavy quarks. The results are checked against results obtained with reweigthing; we find agreement within the estimated errors. The method allows us to go to previously unaccessible high densities.
Open superstring field theory I: gauge fixing, ghost structure, and propagator
Kroyter, Michael
The WZW form of open superstring field theory has linearized gauge invariances associated with the BRST operator Q and the zero mode ? [subscript 0] of the picture minus-one fermionic superconformal ghost. We discuss gauge ...
Non-AbelianSU(2)gauge fields through density wave order and strain...
Office of Scientific and Technical Information (OSTI)
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Using leverages for objective analysis of PSMSL tide gauges in Arctic Ocean sea level reconstruction
applied to the tide gauges, using the Peltier ICE-5G model (Peltier, 2004). For this preliminary analysis
Automorphisms in Gauge Theories and the Definition of CP and P
W. Grimus; M. N. Rebelo
1995-06-08T23:59:59.000Z
We study the possibilities to define CP and parity in general gauge theories by utilizing the intimate connection of these discrete symmetries with the group of automorphisms of the gauge Lie algebra. Special emphasis is put on the scalar gauge interactions and the CP invariance of the Yukawa couplings.
ESTIMATION OF SNOW ACCUMULATION IN ANTARCTICA USING AUTOMATED ACOUSTIC DEPTH GAUGE MEASUREMENTS
Wisconsin at Madison, University of
ESTIMATION OF SNOW ACCUMULATION IN ANTARCTICA USING AUTOMATED ACOUSTIC DEPTH GAUGE MEASUREMENTS microwave sounders, snow gauges, or radar are not feasible or not available in Antarctica at the present precipitation, remains largely unknown. Acoustic depth gauges (ADG) provide the only concrete real
STRATEGIC GEOGRAPHIC POSITIONING OF SEA LEVEL GAUGES TO AID IN EARLY DETECTION OF TSUNAMIS IN THE
Meyers, Steven D.
for coastal sea level gauges intended to serve as elements of a regional tsunami warning system. The goal gauges will assist in developing a tsunami warning system (TWS) for the IAS by the National OceanicSTRATEGIC GEOGRAPHIC POSITIONING OF SEA LEVEL GAUGES TO AID IN EARLY DETECTION OF TSUNAMIS
Transient Nature of Generalized Coulomb Gauge A Mathematical Key to Color Confinement and Mass-Gap
Transient Nature of Generalized Coulomb Gauge Â A Mathematical Key to Color Confinement and Mass to avoid non-locality of the action when generalized Coulomb gauge is imposed, the implementation of the non-abelian Gauss law for infinitesimal time-period over the space of gauge potentials in path
Environmental radiological monitoring of air, rain, and snow on and near the Hanford Site, 1945-1957
Hanf, R.W.; Thiede, M.E.
1994-03-01T23:59:59.000Z
This report is a result of the Hanford Environmental Dose Reconstruction (HEDR) Project. The goal of the HEDR Project is to estimate the radiation dose that individuals could have received from emissions since 1944 at the Hanford Site near Richland, Washington. Members of the HEDR Project`s Environmental Monitoring Data Task have developed databases of historical environmental measurements of such emissions. Hanford documents were searched for information on the radiological monitoring of air, rain, and snow at and near the Hanford Site in Richland, Washington. The monitoring information was reviewed and summarized. The end product is a yearly overview of air, rain, and snow samples as well as ambient radiation levels in the air that were measured from 1945 through 1957. The following information is provided in each annual summary: the media sampled, the constituents (radionuclides) measured/reported, the sampling locations, the sampling frequencies, the sampling methods, and the document references. For some years a notes category is included that contains additional useful information. For the years 1948 through 1957, tables summarizing the sampling locations for the various sample media are also included in the appendix. A large number of documents were reviewed to obtain the information in this report. A reference list is attached to the end of each annual summary. All of the information summarized here was obtained from reports originating at Hanford. These reports are all publicly available and can be found in the Richland Operations Office (RL) public reading room. The information in this report has been compiled without analysis and should only be used as a guide to the original documents.
Lovley, Derek
Microbial Fuel Cells - Solar Times http://solar.rain-barrel.net/microbial-fuel-cells/ 1 of 3 6/28/2006 11:32 AM Microbial Fuel Cells Posted in Alternative Energy by admin. The other end of solar energy? As the search for fuel cells goes on, many environmentalists give all their attention to solar energy
Polz, Martin
PROBLEM Rainwater harvesting systems that collect and convey rain- water from roofs to storage-yearrecord Rigorous analysis of rainwater harvesting system design can improve reliability and water quality CEE-yield of the rainwater harvesting systems, defining reliability as days per year on which the community's water de- mand
Cartan gravity, matter fields, and the gauge principle
Westman, Hans F., E-mail: hwestman74@gmail.com [Imperial College Theoretical Physics, Huxley Building, London, SW7 2AZ (United Kingdom); Zlosnik, Tom G., E-mail: t.zlosnik@imperial.ac.uk [Instituto de Física Fundamental, CSIC, Serrano 113-B, 28006 Madrid (Spain)
2013-07-15T23:59:59.000Z
Gravity is commonly thought of as one of the four force fields in nature. However, in standard formulations its mathematical structure is rather different from the Yang–Mills fields of particle physics that govern the electromagnetic, weak, and strong interactions. This paper explores this dissonance with particular focus on how gravity couples to matter from the perspective of the Cartan-geometric formulation of gravity. There the gravitational field is represented by a pair of variables: (1) a ‘contact vector’ V{sup A} which is geometrically visualized as the contact point between the spacetime manifold and a model spacetime being ‘rolled’ on top of it, and (2) a gauge connection A{sub ?}{sup AB}, here taken to be valued in the Lie algebra of SO(2,3) or SO(1,4), which mathematically determines how much the model spacetime is rotated when rolled. By insisting on two principles, the gauge principle and polynomial simplicity, we shall show how one can reformulate matter field actions in a way that is harmonious with Cartan’s geometric construction. This yields a formulation of all matter fields in terms of first order partial differential equations. We show in detail how the standard second order formulation can be recovered. In particular, the Hodge dual, which characterizes the structure of bosonic field equations, pops up automatically. Furthermore, the energy–momentum and spin-density three-forms are naturally combined into a single object here denoted the spin-energy–momentum three-form. Finally, we highlight a peculiarity in the mathematical structure of our first-order formulation of Yang–Mills fields. This suggests a way to unify a U(1) gauge field with gravity into a SO(1,5)-valued gauge field using a natural generalization of Cartan geometry in which the larger symmetry group is spontaneously broken down to SO(1,3)×U(1). The coupling of this unified theory to matter fields and possible extensions to non-Abelian gauge fields are left as open questions. -- Highlights: •Develops Cartan gravity to include matter fields. •Coupling to gravity is done using the standard gauge prescription. •Matter actions are manifestly polynomial in all field variables. •Standard equations recovered on-shell for scalar, spinor and Yang–Mills fields. •Unification of a U(1) field with gravity based on the orthogonal group SO(1,5)
A proposal for a manifestly gauge invariant and universal calculus in Yang-Mills theory
Arnone, S; Morris, T R; Arnone, Stefano; Gatti, Antonio; Morris, Tim R.
2003-01-01T23:59:59.000Z
We uncover a method of calculation that proceeds at every step without fixing the gauge or specifying details of the regularisation scheme. Results are obtained by iterated use of integration by parts and gauge invariance identities. The initial stages can even be computed diagrammatically. The method is formulated within the framework of an exact renormalization group for SU(N) Yang-Mills gauge theory, incorporating an effective cutoff through a manifest spontaneously broken SU(N|N) gauge invariance. We demonstrate the technique with a compact calculation of the one-loop beta function, achieving a manifestly universal result, and without gauge fixing, for the first time at finite N.
A proposal for a manifestly gauge invariant and universal calculus in Yang-Mills theory
Stefano Arnone; Antonio Gatti; Tim R. Morris
2002-09-20T23:59:59.000Z
We uncover a method of calculation that proceeds at every step without fixing the gauge or specifying details of the regularisation scheme. Results are obtained by iterated use of integration by parts and gauge invariance identities. The initial stages can even be computed diagrammatically. The method is formulated within the framework of an exact renormalization group for SU(N) Yang-Mills gauge theory, incorporating an effective cutoff through a manifest spontaneously broken SU(N|N) gauge invariance. We demonstrate the technique with a compact calculation of the one-loop beta function, achieving a manifestly universal result, and without gauge fixing, for the first time at finite N.
All-order Finiteness of the Higgs Boson Mass in the Dynamical Gauge-Higgs Unification
Yutaka Hosotani
2006-07-06T23:59:59.000Z
In the dynamical gauge-Higgs unification, it is shown that the mass of the Higgs boson (4D scalar field) in U(1) gauge theory in $M^4 \\times T^n$ ($n=1,2,3,...$) is finite to all order in perturbation theory as a consequence of the large gauge invariance. It is conjectured that the Higgs boson mass is finite in non-Abelian gauge theory in $M^4 \\times S^1$, $M^4 \\times (S^1/Z_2)$ and the Randall-Sundrum warped spacetime to all order in the rearranged perturbation theory where the large gauge invariance is maintained.
Gauge invariant regularisation via SU(N|N)
Stefano Arnone; Yuri A. Kubyshin; Tim R. Morris; John F. Tighe
2001-11-25T23:59:59.000Z
We construct a gauge invariant regularisation scheme for pure SU(N) Yang-Mills theory in fixed dimension four or less (for N = infinity in all dimensions), with a physical cutoff scale Lambda, by using covariant higher derivatives and spontaneously broken SU(N|N) supergauge invariance. Providing their powers are within certain ranges, the covariant higher derivatives cure the superficial divergence of all but a set of one-loop graphs. The finiteness of these latter graphs is ensured by properties of the supergroup and gauge invariance. In the limit Lambda tends to infinity, all the regulator fields decouple and unitarity is recovered in the renormalized pure SU(N) Yang-Mills theory. By demonstrating these properties, we prove that the regularisation works to all orders in perturbation theory.
The Electromagnetic Field as a Synchrony Gauge Field
Bock, Robert D
2015-01-01T23:59:59.000Z
Building on our previous work, we investigate the identification of the electromagnetic field as a local gauge field of a restricted group of synchrony transformations. We begin by arguing that the inability to measure the one-way speed of light independent of a synchronization scheme necessitates that physical laws must be reformulated without distant simultaneity. As a result, we are forced to introduce a new operational definition of time which leads to a fundamental space-time invariance principle that is related to a subset of the synchrony group. We identify the gauge field associated with this new invariance principle with the electromagnetic field. Consequently, the electromagnetic field acquires a space-time interpretation, as suggested in our previous work. In addition, we investigate the static, spherically symmetric solution of the resulting field equations. Also, we discuss implications of the present work for understanding the tension between classical and quantum theory.
Gauge field, strings, solitons, anomalies and the speed of life
Niemi, Antti J
2014-01-01T23:59:59.000Z
It's been said that "mathematics is biology's next microscope, only better; biology is mathematics' next physics, only better". Here we aim for something even better. We try to combine mathematical physics and biology into a picoscope of life. For this we merge techniques which have been introduced and developed in modern mathematical physics, largely by Ludvig Faddeev to describe objects such as solitons and Higgs and to explain phenomena such as anomalies in gauge fields. We propose a synthesis that can help to resolve the protein folding problem, one of the most important conundrums in all of science. We apply the concept of gauge invariance to scrutinize the extrinsic geometry of strings in three dimensional space. We evoke general principles of symmetry in combination with Wilsonian universality and derive an essentially unique Landau-Ginzburg energy that describes the dynamics of a generic string-like configuration in the far infrared. We observe that the energy supports topological solitons, that perta...
Electromagnetic gauge invariance of chiral hybrid quark models
Koepf, W.; Henley, E.M. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States))
1994-04-01T23:59:59.000Z
In this work, we investigate the question whether the conventional analysis of the electromagnetic form factors of the nucleon, evaluated in the framework of the cloudy bag model (CBM) or other chirally invariant hybrid quark models utilizing the same philosophy, is gauge invariant In order to address that point, we first formulate the CBM in a style that resembles the technique of loop integrals. Evaluating the self-energy and the electromagnetic form factors of the nucleon in that manner, and comparing with the standard analysis where nonrelativistic perturbation theory is used, allows us to show that our approach is appropriate and to point out what approximations are made in the standard derivation of the model. From the form of those loop integrals, we then show that additional diagrams are needed to preserve electromagnetic gauge invariance and we assess the corresponding corrections.
Tensor networks for Lattice Gauge Theories and Atomic Quantum Simulation
E. Rico; T. Pichler; M. Dalmonte; P. Zoller; S. Montangero
2014-06-07T23:59:59.000Z
We show that gauge invariant quantum link models, Abelian and non-Abelian, can be exactly described in terms of tensor networks states. Quantum link models represent an ideal bridge between high-energy to cold atom physics, as they can be used in cold-atoms in optical lattices to study lattice gauge theories. In this framework, we characterize the phase diagram of a (1+1)-d quantum link version of the Schwinger model in an external classical background electric field: the quantum phase transition from a charge and parity ordered phase with non-zero electric flux to a disordered one with a net zero electric flux configuration is described by the Ising universality class.
LHC constraints on gauge boson couplings to dark matter
Crivellin, Andreas; Hibbs, Anthony
2015-01-01T23:59:59.000Z
Collider searches for energetic particles recoiling against missing transverse energy allow to place strong bounds on the interactions between dark matter (DM) and standard model particles. In this article we update and extend LHC constraints on effective dimension-7 operators involving DM and electroweak gauge bosons. A concise comparison of the sensitivity of the mono-photon, mono-W, mono-Z, mono-W/Z, invisible Higgs-boson decays in the vector boson fusion mode and the mono-jet channel is presented. Depending on the parameter choices, either the mono-photon or the mono-jet data provide the most stringent bounds at the moment. We furthermore explore the potential of improving the current 8 TeV limits at 14 TeV. Future strategies capable of disentangling the effects of the different effective operators involving electroweak gauge bosons are discussed as well.
Chiral symmetry of graphene and strong coupling lattice gauge theory
Yasufumi Araki; Tetsuo Hatsuda
2010-10-28T23:59:59.000Z
We model the electrons on a monolayer graphene in terms of the compact and non-compact U(1) lattice gauge theories. The system is analyzed by the strong coupling expansion and is shown to be an insulator due to dynamical gap formation in/around the strong coupling limit. This is similar to the spontaneous chiral symmetry breaking in strong coupling gauge theories. The results from the compact and non-compact formulations are compared up to the next-to-leading order of the strong coupling expansion. Excitonic modes and their dispersion relations in the insulating phase are also investigated: it is found that there arises a pseudo-Nambu--Goldstone mode obeying the Gell-Mann--Oakes--Renner type formula.
Thermodynamics of SU(3) gauge theory at fixed lattice spacing
T. Umeda; S. Ejiri; S. Aoki; T. Hatsuda; K. Kanaya; Y. Maezawa; H. Ohno
2008-10-09T23:59:59.000Z
We study thermodynamics of SU(3) gauge theory at fixed scales on the lattice, where we vary temperature by changing the temporal lattice size N_t=(Ta_t)^{-1}. In the fixed scale approach, finite temperature simulations are performed on common lattice spacings and spatial volumes. Consequently, we can isolate thermal effects in observables from other uncertainties, such as lattice artifact, renormalization factor, and spatial volume effect. Furthermore, in the EOS calculations, the fixed scale approach is able to reduce computational costs for zero temperature subtraction and parameter search to find lines of constant physics, which are demanding in full QCD simulations. As a test of the approach, we study the thermodynamics of the SU(3) gauge theory on isotropic and anisotropic lattices. In addition to the equation of state, we calculate the critical temperature and the static quark free energy at a fixed scale.
Axion inflation with gauge field production and primordial black holes
Edgar Bugaev; Peter Klimai
2014-10-19T23:59:59.000Z
We study the process of primordial black hole (PBH) formation at the beginning of radiation era for the cosmological scenario in which the inflaton is a pseudo-Nambu-Goldstone boson (axion) and there is a coupling of the inflaton with some gauge field. In this model inflation is accompanied by the gauge quanta production and a strong rise of the curvature power spectrum amplitude at small scales (along with non-Gaussianity) is predicted. We show that data on PBH searches can be used for a derivation of essential constraints on the model parameters in such an axion inflation scenario. We compare our numerical results with the similar results published earlier, in the work by Linde et al.
On the geometry of quiver gauge theories (Stacking exceptional collections)
Christopher P. Herzog; Robert L. Karp
2008-02-03T23:59:59.000Z
In this paper we advance the program of using exceptional collections to understand the gauge theory description of a D-brane probing a Calabi-Yau singularity. To this end, we strengthen the connection between strong exceptional collections and fractional branes. To demonstrate our ideas, we derive a strong exceptional collection for every Y^{p,q} singularity, and also prove that this collection is simple.
Gauged Nambu-Jona-Lasinio model and axionic QCD string
Chi Xiong
2014-12-30T23:59:59.000Z
We propose an axionic QCD string scenario based on the original flux-tube model by Kogut and Susskind, and then incorporate it into a gauged Nambu-Jona-Lasinio (NJL) model. Axial anomaly is studied by a new topological coupling from the string side, and by the 't Hooft vortex from the NJL side, respectively. The nontrivial phase distribution of the quark condensate plays an important role in this scenario.
Light quark spectrum with improved gauge and fermion actions
MILC Collaboration; Claude Bernard; Tom DeGrand; Carleton DeTar; Steven Gottlieb; Urs M. Heller; Jim Hetrick; Craig McNeile; Kari Rummukainen; Bob Sugar; Doug Toussaint; Matthew Wingate
1997-11-08T23:59:59.000Z
We report on a study of the light quark spectrum using an improved gauge action and both Kogut-Susskind and Naik quark actions. We have studied six different lattice spacings, corresponding to plaquette couplings ranging from 6.8 to 7.9, with five to six quark masses per coupling. We compare the two quark actions in terms of the spectrum and restoration of flavor symmetry. We also compare these results with those from the conventional action.
Self-avoiding effective strings in lattice gauge theories
M. Caselle; F. Gliozzi
1991-11-28T23:59:59.000Z
It is shown that the effective string recently introduced to describe the long distance dynamics of 3D gauge systems in the confining phase has an intriguing description in terms of models of 2D self-avoiding walks in the dense phase. The deconfinement point, where the effective string becomes N=2 supersymmetric, may then be interpreted as the tricritical Theta point where the polymer chain undergoes a collapse transition. As a consequence, a universal value of the deconfinement temperature is predicted.
Reaction rates from pressure-gauge measurements in reacting explosives
Ginsberg, M.J.; Anderson, A.B.; Wackerle, J.
1981-01-01T23:59:59.000Z
The proper hydrodynamic data and an equation of state are sufficient to describe quantitatively the reaction rates of explosives during the shock-to-detonation transition. Manganin pressure gauges embedded in the reacting explosive have provided these data for the explosives PETN, PBX 9404, TATB, and TNT. Once a pressure-field history has been assembled from individual pressure histories at different depths in the explosive, the conservation equations can be applied in a Lagrangian analysis of the data. The combination of a reactant-product equation of state with this analysis then allows the calculation of the extent of reaction and reaction rate. Successful correlation of the calculated reaction rate values with other thermodynamic variables, such as pressure or temperature, allows formulation of a rate law and the prediction of initiation behavior under circumstances quite different from the experiments that led to the rate law. The best dynamic piezoresistive pressure gauge for most applications would have a substantial output voltage and present negligible disturbance to the flow. In explosives, however, requirements for survival in the extreme temperature and pressure environment encountered by the gauge dictate compromise. Low electrical resistance (approx. 20 m..cap omega..) helps to minimize shunt conductivity failures, but this drastically reduces output and demands that much attention be given to reducingnoise. Although relatively thick insulation perturbs the flow to some extent, survivability requirements dictate its use. Pressure measurements in reactive flow can now be made routinely with gauges that successfully produce data leading to a description of the flow and a powerful predictive capability.
Continuum Thermodynamics of the SU(N) Gauge Theory
Saumen Datta; Sourendu Gupta
2010-12-30T23:59:59.000Z
The thermodynamics of the deconfined phase of the SU(N) gauge theory is studied. Careful study is made of the approach to the continuum limit. The latent heat of the deconfinement transition is studied, for the theories with 3, 4 and 6 colors. Continuum estimates of various thermodynamic quantities are studied, and the approach to conformality investigated. The bulk thermodynamic quantities at different N are compared, to investigate the validity of 't Hooft scaling at these values of N.
Testing numerical relativity with the shifted gauge wave
Maria C. Babiuc; Bela Szilagyi; Jeffrey Winicour
2006-02-17T23:59:59.000Z
Computational methods are essential to provide waveforms from coalescing black holes, which are expected to produce strong signals for the gravitational wave observatories being developed. Although partial simulations of the coalescence have been reported, scientifically useful waveforms have so far not been delivered. The goal of the AppleswithApples (AwA) Alliance is to design, coordinate and document standardized code tests for comparing numerical relativity codes. The first round of AwA tests have now being completed and the results are being analyzed. These initial tests are based upon periodic boundary conditions designed to isolate performance of the main evolution code. Here we describe and carry out an additional test with periodic boundary conditions which deals with an essential feature of the black hole excision problem, namely a non-vanishing shift. The test is a shifted version of the existing AwA gauge wave test. We show how a shift introduces an exponentially growing instability which violates the constraints of a standard harmonic formulation of Einstein's equations. We analyze the Cauchy problem in a harmonic gauge and discuss particular options for suppressing instabilities in the gauge wave tests. We implement these techniques in a finite difference evolution algorithm and present test results. Although our application here is limited to a model problem, the techniques should benefit the simulation of black holes using harmonic evolution codes.
M5-branes, toric diagrams and gauge theory duality
Ling Bao; Elli Pomoni; Masato Taki; Futoshi Yagi
2012-02-03T23:59:59.000Z
In this article we explore the duality between the low energy effective theory of five-dimensional N=1 SU(N)^{M-1} and SU(M)^{N-1} linear quiver gauge theories compactified on S^1. The theories we study are the five-dimensional uplifts of four-dimensional superconformal linear quivers. We study this duality by comparing the Seiberg-Witten curves and the Nekrasov partition functions of the two dual theories. The Seiberg-Witten curves are obtained by minimizing the worldvolume of an M5-brane with nontrivial geometry. Nekrasov partition functions are computed using topological string theory. The result of our study is a map between the gauge theory parameters, i.e., Coulomb moduli, masses and UV coupling constants, of the two dual theories. Apart from the obvious physical interest, this duality also leads to compelling mathematical identities. Through the AGTW conjecture these five-dimentional gauge theories are related to q-deformed Liouville and Toda SCFTs in two-dimensions. The duality we study implies the relations between Liouville and Toda correlation functions through the map we derive.
Hall viscosity from elastic gauge fields in Dirac crystals
Alberto Cortijo; Yago Ferreirós; Karl Landsteiner; María A. H. Vozmediano
2015-06-16T23:59:59.000Z
The combination of Dirac physics and elasticity has been explored at length in graphene where the so--called "elastic gauge fields" have given rise to an entire new field of research and applications: Straintronics. The fact that these elastic fields couple to fermions as the electromagnetic field, implies that many electromagnetic responses will have elastic counterparts not explored before. In this work we will first show that the presence of elastic gauge fields will be the rule rather than the exception in most of the topologically non--trivial materials in two and three dimensions. In particular we will extract the elastic gauge fields associated to the recently observed Weyl semimetals, the "three dimensional graphene". As it is known, quantum electrodynamics suffers from the chiral anomaly whose consequences have been recently explored in matter systems. We will show that, associated to the physics of the anomalies, and as a counterpart of the Hall conductivity, elastic materials will have a Hall viscosity in two and three dimensions with a coefficient orders of magnitude bigger than the previously studied response. The magnitude and generality of the new effect will greatly improve the chances for the experimental observation of this topological, non dissipative response.
Non-linear power spectra in the synchronous gauge
Jai-chan Hwang; Hyerim Noh; Donghui Jeong; Jinn-Ouk Gong; Sang Gyu Biern
2014-08-20T23:59:59.000Z
We study the non-linear corrections to the matter and velocity power spectra in the synchronous gauge (SG). We consider the perturbations up to third order in a zero-pressure fluid in flat cosmological background, which is relevant for the non-linear growth of cosmic structure. As a result, we point out that the SG is an inappropriate coordinate choice when handling the non-linear growth of the large-scale structure. Although the equations in the SG happen to coincide with those in the comoving gauge (CG) to linear order, they differ from second order. In particular, the second order hydrodynamic equations in the the SG are apparently in the Lagrangian form, whereas those in the CG are in the Eulerian form. Thus, the non-linear power spectra naively presented in the original SG show strange behavior quite different from the result of the Newtonian theory even on sub-horizon scales. The power spectra in the SG show regularized behaviors only after we introduce convective terms in the second order so that the equations in two gauges coincide to the second order.
Supersymmetric black holes and attractors in gauged supergravity with hypermultiplets
Samuele Chimento; Dietmar Klemm; Nicolò Petri
2015-04-13T23:59:59.000Z
We consider four-dimensional $N=2$ supergravity coupled to vector- and hypermultiplets, where abelian isometries of the quaternionic K\\"ahler hypermultiplet scalar manifold are gauged. Using the recipe given by Meessen and Ort\\'{\\i}n in arXiv:1204.0493, we analytically construct a supersymmetric black hole solution for the case of just one vector multiplet with prepotential ${\\cal F}=-i\\chi^0\\chi^1$, and the universal hypermultiplet. This solution has a running dilaton, and it interpolates between $\\text{AdS}_2\\times\\text{H}^2$ at the horizon and a hyperscaling-violating type geometry at infinity, conformal to $\\text{AdS}_2\\times\\text{H}^2$. It carries two magnetic charges that are completely fixed in terms of the parameters that appear in the Killing vector used for the gauging. In the second part of the paper, we extend the work of Bellucci et al. on black hole attractors in gauged supergravity to the case where also hypermultiplets are present. The attractors are shown to be governed by an effective potential $V_{\\text{eff}}$, which is extremized on the horizon by all the scalar fields of the theory. Moreover, the entropy is given by the critical value of $V_{\\text{eff}}$. In the limit of vanishing scalar potential, $V_{\\text{eff}}$ reduces (up to a prefactor) to the usual black hole potential.
Supersymmetric black holes and attractors in gauged supergravity with hypermultiplets
Chimento, Samuele; Petri, Nicolò
2015-01-01T23:59:59.000Z
We consider four-dimensional $N=2$ supergravity coupled to vector- and hypermultiplets, where abelian isometries of the quaternionic K\\"ahler hypermultiplet scalar manifold are gauged. Using the recipe given by Meessen and Ort\\'{\\i}n in arXiv:1204.0493, we analytically construct a supersymmetric black hole solution for the case of just one vector multiplet with prepotential ${\\cal F}=-i\\chi^0\\chi^1$, and the universal hypermultiplet. This solution has a running dilaton, and it interpolates between $\\text{AdS}_2\\times\\text{H}^2$ at the horizon and a hyperscaling-violating type geometry at infinity, conformal to $\\text{AdS}_2\\times\\text{H}^2$. It carries two magnetic charges that are completely fixed in terms of the parameters that appear in the Killing vector used for the gauging. In the second part of the paper, we extend the work of Bellucci et al. on black hole attractors in gauged supergravity to the case where also hypermultiplets are present. The attractors are shown to be governed by an effective potent...
Anomaly of Tensionless String in Light-cone Gauge
Kenta Murase
2015-03-04T23:59:59.000Z
The classical tensionless string theory has the spacetime conformal symmetry. We expect and require that the quantum tensionless string theory has it too. In the BRST quantization method, the theory has no spacetime conformal anomaly in two dimensions. On the other hand, in the light-cone gauge quantization without the mode expansion, the theory in $D>3$ has the spacetime conformal anomaly in the traceless part of $[\\mathcal{J}^{-I}, \\mathcal{K}^{J}]$ in some operator order. In this paper, we consider a tensionless closed bosonic string in the light-cone gauge and investigate the spacetime conformal anomaly in the theory with the mode expansion. The appearance of the spacetime conformal anomaly in the light-cone gauge is different between the case of $D>3$ and the case of $D=3$ and depends on the choice of the operator order. Therefore we must consider dangerous commutators in the spacetime conformal symmetry of $D>3$ and $D=3$ in each operator order separately. Specifically we calculate dangerous commutators, $[\\mathcal{J}^{-I},\\mathcal{K}^{K}]$ in $D>3$ and $\\tilde{\\mathcal{K}}^{-}\\equiv -i[\\mathcal{J}^{-}, \\tilde{\\mathcal{K}}^{-}]$ and $[\\mathcal{J}^{-}, \\tilde{\\mathcal{K}}^{-}]$ in $D=3$, in two types of the operator order.
Anomaly of Tensionless String in Light-cone Gauge
Murase, Kenta
2015-01-01T23:59:59.000Z
The classical tensionless string theory has the spacetime conformal symmetry. We expect and require that the quantum tensionless string theory has it too. In the BRST quantization method, the theory has no spacetime conformal anomaly in two dimensions. On the other hand, in the light-cone gauge quantization without the mode expansion, the theory in $D>3$ has the spacetime conformal anomaly in the traceless part of $[\\mathcal{J}^{-I}, \\mathcal{K}^{J}]$ in some operator order. In this paper, we consider a tensionless closed bosonic string in the light-cone gauge and investigate the spacetime conformal anomaly in the theory with the mode expansion. The appearance of the spacetime conformal anomaly in the light-cone gauge is different between the case of $D>3$ and the case of $D=3$ and depends on the choice of the operator order. Therefore we must consider dangerous commutators in the spacetime conformal symmetry of $D>3$ and $D=3$ in each operator order separately. Specifically we calculate dangerous commutators...
Gauge theories in the light-cone representation
Nakawaki, Yuji [Division of Physics and Mathematics, Faculty of Engineering, Setsunan University, Osaka 572-8508 (Japan); McCartor, Gary [Department of Physics, SMU, Dallas, Texas 75275 (United States)
1999-11-22T23:59:59.000Z
We attempt in McCartor and Robertson's framework to formulate a perturbation theory of light-cone axial gauge QED in which zero-mode fields play roles as regulator fields yielding well-defined Mandelstam-Leibbrandt form of gauge field propagator. We find that zero-mode fields make up for degrees of freedom of A{sub +} and its canonical conjugate in the light-cone temporal gauge formulation and that they are retained in the interaction term j{sup +}A{sub +} through A{sub +}, if and only if the integral {integral}{sub -{infinity}}{sup {infinity}}dx{sup -}j{sub -} does not vanish. It is pointed out that from the boundary surface contributions T{sub ++}(x{sup -}={+-}{infinity}), which are added to obtain P{sub +} identical to those in ordinary coordinates, an infinite number of noncovariant interaction terms might be obtained so as to cancel corresponding infinite number of noncovariant diagrams yielded by the contact term of the Fermion propagator.
Observation of the Chern-Simons gauge anomaly
Sunil Mittal; Sriram Ganeshan; Jingyun Fan; Abolhassan Vaezi; Mohammad Hafezi
2015-04-22T23:59:59.000Z
Topological Quantum Field Theories (TQFTs) are powerful tools to describe universal features of topological orders. A hallmark example of a TQFT is the 2+1 D Chern-Simons (CS) theory which describes topological properties of both integer and fractional quantum Hall effects. The gauge invariant form of the CS theory with boundaries, encompassing both edge and bulk terms, provides an unambiguous way to relate bulk topological invariants to the edge dynamics. This bulk-edge correspondence is manifested as a gauge anomaly of the chiral dynamics at the edge, and provides a direct insight into the bulk topological order. Such an anomaly has never been directly observed in an experiment. In this work, we experimentally implement the integer quantum Hall model in a photonic system, described by the corresponding CS theory. By selectively manipulating and probing the edge, we exploit the gauge anomaly of the CS theory, for the first time. The associated spectral edge flow allows us to unambiguously measure topological invariants, i.e., the winding number of the edge states. This experiment provides a new approach for direct measurement of topological invariants, independent of the microscopic details, and thus could be extended to probe strongly correlated topological orders.
String Organization of Field Theories: Duality and Gauge Invariance
Y. J. Feng; C. S. Lam
1994-09-14T23:59:59.000Z
String theories should reduce to ordinary four-dimensional field theories at low energies. Yet the formulation of the two are so different that such a connection, if it exists, is not immediately obvious. With the Schwinger proper-time representation, and the spinor helicity technique, it has been shown that field theories can indeed be written in a string-like manner, thus resulting in simplifications in practical calculations, and providing novel insights into gauge and gravitational theories. This paper continues the study of string organization of field theories by focusing on the question of local duality. It is shown that a single expression for the sum of many diagrams can indeed be written for QED, thereby simulating the duality property in strings. The relation between a single diagram and the dual sum is somewhat analogous to the relation between a old- fashioned perturbation diagram and a Feynman diagram. Dual expressions are particularly significant for gauge theories because they are gauge invariant while expressions for single diagrams are not.
arXiv:1311.1056v1[hep-lat]5Nov2013 Adaptive gauge cooling for complex Langevin
Aarts, Gert
that makes progress possible [4Â6]. 2. Gauge cooling In nonabelian gauge theories, complex Langevin dynamicsarXiv:1311.1056v1[hep-lat]5Nov2013 Adaptive gauge cooling for complex Langevin dynamics Lorenzo configuration space during a complex Langevin process requires the use of SL(N,C) gauge cooling, in order
The Static Quark Potential from the Gauge Independent Abelian Decomposition
Nigel Cundy; Y. M. Cho; Weonjong Lee
2015-03-24T23:59:59.000Z
We investigate the relationship between colour confinement and the gauge independent Cho-Duan-Ge Abelian decomposition. The decomposition is defined in terms of a colour field $n$; the principle novelty of our study is that we have defined this field in terms of the eigenvectors of the Wilson Loop. This establishes an equivalence between the path ordered integral of the non-Abelian gauge fields with an integral over an Abelian restricted gauge field which is tractable both theoretically and numerically in lattice QCD. We circumvent path ordering without needing an additional path integral. By using Stokes' theorem, we can compute the Wilson Loop in terms of a surface integral over a restricted field strength, and show that the restricted field strength may be dominated by certain structures, which occur when one of the quantities parametrising the colour field $n$ winds itself around a non-analyticity in the colour field. If they exist, these structures will lead to a area law scaling for the Wilson Loop and provide a mechanism for quark confinement. We search for these structures in quenched lattice QCD. We perform the Abelian decomposition, and compare the electric and magnetic fields with the patterns expected theoretically. We find that the restricted field strength is dominated by objects which may be peaks a single lattice spacing in size or extended string-like lines of electromagnetic flux. The objects are not isolated monopoles, as they generate electric fields in addition to magnetic fields, and the fields are not spherically symmetric, but may be either caused by a monopole/anti-monopole condensate, some other types of topological objects or a combination of these. Removing these peaks removes the area law scaling of the string tension, suggesting that they are responsible for confinement.
Gauge-Invariant Perturbations in Hybrid Quantum Cosmology
Laura Castelló Gomar; Mercedes Martín-Benito; Guillermo A. Mena Marugán
2015-03-12T23:59:59.000Z
We consider cosmological perturbations around homogeneous and isotropic spacetimes minimally coupled to a scalar field and present a formulation which is designed to preserve covariance. We truncate the action at quadratic perturbative order and particularize our analysis to flat compact spatial sections and a field potential given by a mass term, although the formalism can be extended to other topologies and potentials. The perturbations are described in terms of Mukhanov-Sasaki gauge invariants, linear perturbative constraints, and variables canonically conjugate to them. This set is completed into a canonical one for the entire system, including the homogeneous degrees of freedom. We find the global Hamiltonian constraint of the model, in which the contribution of the homogeneous sector is corrected with a term quadratic in the perturbations, that can be identified as the Mukhanov-Sasaki Hamiltonian in our formulation. We then adopt a hybrid approach to quantize the model, combining a quantum representation of the homogeneous sector with a more standard field quantization of the perturbations. Covariance is guaranteed in this approach inasmuch as no gauge fixing is adopted. Next, we adopt a Born-Oppenheimer ansatz for physical states and show how to obtain a Schr\\"odinger-like equation for the quantum evolution of the perturbations. This evolution is governed by the Mukhanov-Sasaki Hamiltonian, with the dependence on the homogeneous geometry evaluated at quantum expectation values, and with a time parameter defined also in terms of suitable expectation values on that geometry. Finally, we derive effective equations for the dynamics of the Mukhanov-Sasaki gauge invariants, that include quantum contributions, but have the same ultraviolet limit as the classical equations. They provide the master equation to extract predictions about the power spectrum of primordial scalar perturbations.
A Bicycle Built for Two: The Galilean and U(1) Gauge Invariance of the Schrödinger Field
V. Colussi; S. Wickramasekara
2008-03-04T23:59:59.000Z
This paper undertakes a study of the nature of the force associated with the local U (1) gauge symmetry of a non-relativistic quantum particle. To ensure invariance under local U (1) symmetry, a matter field must couple to a gauge field. We show that such a gauge field necessarily satisfies the Maxwell equations, whether the matter field coupled to it is relativistic or non-relativistic. This result suggests that the structure of the Maxwell equations is determined by gauge symmetry rather than the symmetry transformation properties of space-time. In order to assess the validity of this notion, we examine the transformation properties of the coupled matter and gauge fields under Galilean transformations. Our main technical result is the Galilean invariance of the full equations of motion of the U (1) gauge field.
Chaotic Hybrid Inflation with a Gauged B - L
Linda M. Carpenter; Stuart Raby
2014-09-03T23:59:59.000Z
In this paper we present a novel formulation of chaotic hybrid inflation in supergravity. The model includes a waterfall field which spontaneously breaks a gauged $U_1(B-L)$ at a GUT scale. This allows for the possibility of future model building which includes the standard formulation of baryogenesis via leptogenesis with the waterfall field decaying into right-handed neutrinos. We have not considered the following issues in this short paper, i.e. supersymmetry breaking, dark matter or the gravitino or moduli problems. Our focus is on showing the compatibility of the present model with Planck, WMAP and Bicep2 data.
Aspects of the confinement mechanism in Landau gauge QCD
Kai Schwenzer
2008-11-21T23:59:59.000Z
I analyze the IR fixed point structure of Landau gauge QCD. Precisely the fixed point with a strong kinematic singularity of the quark-gluon vertex that proved crucial for the recently proposed confinement mechanism in the quenched approximation is absent in dynamical QCD. Therefore, the IR singularities do not induce asymptotic quark confinement but the long-range interaction is screened by unquenching loops at scales of the order of the quark mass. This provides the prerequisite for a microscopic description of deconfinement and string breaking. The fixed points determine the qualitative form of the heavy quark potential and may be relevant for hot and dense matter.
Instanton Operators in Five-Dimensional Gauge Theories
N. Lambert; C. Papageorgakis; M. Schmidt-Sommerfeld
2015-06-04T23:59:59.000Z
We discuss instanton operators in five-dimensional gauge theories. These are defined as disorder operators which create a non-vanishing second Chern class on a four-sphere surrounding their insertion point. As such they may be thought of as higher-dimensional analogues of three-dimensional monopole (or `t Hooft) operators. We argue that they play an important role in the enhancement of the Lorentz symmetry for maximally supersymmetric Yang-Mills to SO(1,5) at strong coupling.
Lattice Gauge Theory and the Origin of Mass
Kronfeld, Andreas S.
2013-08-01T23:59:59.000Z
Most of the mass of everyday objects resides in atomic nuclei/ the total of the electrons' mass adds up to less than one part in a thousand. The nuclei are composed of nucleons---protons and neutrons---whose nuclear binding energy, though tremendous on a human scale, is small compared to their rest energy. The nucleons are, in turn, composites of massless gluons and nearly massless quarks. It is the energy of these confined objects, via $M=E/c^2$, that is responsible for everyday mass. This article discusses the physics of this mechanism and the role of lattice gauge theory in establishing its connection to quantum chromodynamics.
Graviton propagators in supergravity and noncommutative gauge theory
Kitazawa, Yoshihisa [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan); Department of Particle and Nuclear Physics, Graduate University for Advanced Studies, Tsukuba, Ibaraki 305-0801 (Japan); Nagaoka, Satoshi [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan)
2007-02-15T23:59:59.000Z
We investigate the graviton propagator in the type IIB supergravity background which is dual to 4 dimensional noncommutative gauge theory. We assume that the boundary is located not at the infinity but at the noncommutative scale where the string frame metric exhibits the maximum. We argue that the Neumann boundary condition is the appropriate boundary condition to be adopted at the boundary. We find that the graviton propagator behaves just as that of the 4 dimensional massless graviton. On the other hand, the nonanalytic behaviors of the other Kaluza-Klein modes are not significantly affected by the Neumann boundary condition.
U(1) gauge invariant noncommutative Schroedinger theory and gravity
Muthukumar, B. [Saha Institute of Nuclear Physics, 1/AF, Bidhan nagar, Kolkata-700 064 (India)
2005-05-15T23:59:59.000Z
We consider the complex, massive Klein-Gordon field living in the noncommutative space, and coupled to noncommutative electromagnetic fields. After employing the Seiberg-Witten map to first order, we analyze the noncommutative Klein-Gordon theory as c, which corresponds to the velocity of light, goes to infinity. We show that the theory exhibits a regular 'magnetic' limit only for certain forms of magnetic fields. The resulting theory is nothing but the Schroedinger theory in a gravitational background generated by the gauge fields.
Gauge theories from D7-branes over vanishing 4-cycles
Franco, Sebastian; /Santa Barbara, KITP; Torroba, Gonzalo; /SLAC /Stanford U., Phys. Dept.
2010-12-16T23:59:59.000Z
We study quiver gauge theories on D7-branes wrapped over vanishing holomorphic 4-cycles. We investigate how to incorporate O7-planes and/or flavor D7-branes, which are necessary to cancel anomalies. These theories are chiral, preserve four supercharges and exhibit very rich infrared dynamics. Geometric transitions and duality in the presence of O-planes are analyzed. We study the Higgs branch of these quiver theories, showing the emergence of fuzzy internal dimensions. This branch is related to noncommutative instantons on the divisor wrapped by the seven-branes. Our results have a natural application to the recently introduced F(uzz) limit of F-theory.
Lorentz covariance and gauge invariance in the proton spin problem
S. C. Tiwari
2014-09-01T23:59:59.000Z
In this brief note insightful remarks are made on the controversy on the decomposition of the proton spin into the spin and orbital angular momenta of quarks and gluons. It is argued that the difference in the perception on the nature of the problem is the main reason for the persistent disputes. There is no decomposition that simultaneously satisfies the twin principles of manifest Lorentz covariance and gauge invariance, and partial considerations hide likely inconsistencies. It is suggested that field equations and matter (i. e. electron in QED and quarks in QCD) equations must be analyzed afresh rather than beginning with the expressions of total angular momentum; canonical or otherwise.
Emergent gravity/Non-linear U(1) gauge theory correspondence
Supriya Kar; K. Priyabrat Pandey; Abhishek K. Singh; Sunita Singh
2010-02-21T23:59:59.000Z
Kaluza-Klein gravity is revisted, with renewed interest, in a type IIB string theory on $S^1\\times K3$. The irreducible curvature tensors are worked out in the, T-dual, emergent gravity in 4D to yield a non-linear U(1) gauge theory. Interestingly, the T-duality may be seen to describe an open/closed string duality at a self-dual string coupling. The obtained deformation in $AdS_5$ black hole is analyzed to introduce the notion of temperature in the emergent gravity underlying the recent idea of entropic force.
U(1) Gauge Theory with Villain Action on Spherical Lattices
C. B. Lang; P. Petreczky
1996-07-19T23:59:59.000Z
We have studied the U(1) gauge field theory with Villain (periodic Gaussian) action on spherelike lattices. The effective size of the systems studied ranges from 6 to 16. We do not observe any 2-state signal in the distribution function of the plaquette expectation value at the deconfining phase transition. The observed finite-size scaling behavior is consistent with a second order phase transition. The obtained value of the critical exponent is nu =0.366(12) and thus neither Gaussian (nu = 0.5) nor discontinuous (nu=0.25) type, indicating a nontrivial continuum limit.
Finite Temperature Sum Rules in Lattice Gauge Theory
Harvey B. Meyer
2007-11-05T23:59:59.000Z
We derive non-perturbative sum rules in SU($N$) lattice gauge theory at finite temperature. They relate the susceptibilities of the trace anomaly and energy-momentum tensor to temperature derivatives of the thermodynamic potentials. Two of them have been derived previously in the continuum and one is new. In all cases, at finite latttice spacing there are important corrections to the continuum sum rules that are only suppressed by the bare coupling $g_0^2$. We also show how the discretization errors affecting the thermodynamic potentials can be controlled by computing these susceptibilities.
Hamiltonian lattice gauge theory: wavefunctions on large lattices
J. B. Bronzan
1992-11-10T23:59:59.000Z
We discuss an algorithm for the approximate solution of Schrodinger's equation for lattice gauge theory, using lattice SU(3) as an example. A basis is generated by repeatedly applying an effective Hamiltonian to a ``starting state.'' The resulting basis has a cluster decomposition and long-range correlations. One such basis has about 10^4 states on a 10X10X10 lattice. The Hamiltonian matrix on the basis is sparse, and the elements can be calculated rapidly. The lowest eigenstates of the system are readily calculable.
Chiral Imprint of a Cosmic Gauge Field on Primordial Gravitational Waves
Jannis Bielefeld; Robert R. Caldwell
2014-12-18T23:59:59.000Z
A cosmological gauge field with isotropic stress-energy introduces parity violation into the behavior of gravitational waves. We show that a primordial spectrum of inflationary gravitational waves develops a preferred handedness, left- or right-circularly polarized, depending on the abundance and coupling of the gauge field during the radiation era. A modest abundance of the gauge field would induce parity-violating correlations of the cosmic microwave background temperature and polarization patterns that could be detected by current and future experiments.
G. DiCecio; A. Hart; R. W. Haymaker
1997-09-22T23:59:59.000Z
We derive an Ehrenfest theorem for SU(2) lattice gauge theory which, after Abelian projection, relates the Abelian field strength and a dynamical electric current and defines these operators for finite lattice spacing. Preliminary results from the ongoing numerical test of the relation are presented, including the contributions from gauge fixing and the Faddeev-Popov determinant (the ghost fields) in the maximally Abelian gauge.
National Computational Infrastructure for Lattice Gauge Theory SciDAC-2 Closeout Report
Mackenzie, Paul [Fermilab] [Fermilab; Brower, Richard [Boston University] [Boston University; Karsch, Frithjof [Brookhaven National Laboratory] [Brookhaven National Laboratory; Christ, Norman [Columbia University] [Columbia University; Gottlieb, Steven [Indiana University] [Indiana University; Negele, John [MIT] [MIT; Richards, David [Jefferson National Laboratory] [Jefferson National Laboratory; Toussaint, Doug [Univ. of Arizona] [Univ. of Arizona; Sugar, Robert [Univ. of California at Santa Barbara] [Univ. of California at Santa Barbara; DeTar, Carleton [Univ. of Utah] [Univ. of Utah; Sharpe, Stephen [Univ. of Washington] [Univ. of Washington; DiPierro, Massimo [DePaul University] [DePaul University; Sun, Xian-He [illinois institute of Technology] [illinois institute of Technology; Fowler, Rob [University of North Carolina] [University of North Carolina; Dubey, Abhishek [Vanderbilt University] [Vanderbilt University
2013-07-19T23:59:59.000Z
Under its SciDAC-1 and SciDAC-2 grants, the USQCD Collaboration developed software and algorithmic infrastructure for the numerical study of lattice gauge theories.
$S$-duality in Vafa-Witten theory for non-simply laced gauge groups
Siye Wu
2008-02-14T23:59:59.000Z
Vafa-Witten theory is a twisted N=4 supersymmetric gauge theory whose partition functions are the generating functions of the Euler number of instanton moduli spaces. In this paper, we recall quantum gauge theory with discrete electric and magnetic fluxes and review the main results of Vafa-Witten theory when the gauge group is simply laced. Based on the transformations of theta functions and their appearance in the blow-up formulae, we propose explicit transformations of the partition functions under the Hecke group when the gauge group is non-simply laced. We provide various evidences and consistency checks.
Numerical test of the Gribov-Zwanziger scenario in Landau gauge
Attilio Cucchieri; Tereza Mendes
2010-01-14T23:59:59.000Z
We review the status of lattice simulations of gluon and ghost propagators in Landau gauge, testing predictions of the Gribov-Zwanziger confinement scenario.
The M-theory origin of global properties of gauge theories
Antonio Amariti; Claudius Klare; Domenico Orlando; Susanne Reffert
2015-07-16T23:59:59.000Z
We show that global properties of gauge groups can be understood as geometric properties in M-theory. Different wrappings of a system of N M5-branes on a torus reduce to four-dimensional theories with $A_{N-1}$ gauge algebra and different unitary groups. The classical properties of the wrappings determine the global properties of the gauge theories without the need to impose any quantum conditions. We count the inequivalent wrappings as they fall into orbits of the modular group of the torus, which correspond to the S-duality orbits of the gauge theories.
Effect of the scalar condensate on the linear gauge field response in the Abelian Higgs model
Jakovác, A; Szép, Z; Szep, Zs.
2001-01-01T23:59:59.000Z
The effective equations of motion for low-frequency mean gauge fields in the Abelian Higgs model are investigated in the presence of a scalar condensate, near the high temperature equilibrium. We determine the current induced by an inhomogeneous background gauge field in the linear response approximation up to order $e^4$, assuming adiabatic variation of the scalar fields. The physical degrees of freedom are found and a physical gauge choice for the numerical study of the combined Higgs+gauge evolution is proposed.
Screening in (2+1)D pure gauge theory at high temperatures
E. Laermann; C. Legeland; B. Petersson
1995-01-23T23:59:59.000Z
We compute heavy quark potentials in pure gauge $SU(3)$ at high temperatures in $2+1$ dimensions and confront them with expectations emerging from perturbative calculations.
Jet quenching in hot strongly coupled gauge theories simplified
Peter Arnold; Diana Vaman
2011-01-13T23:59:59.000Z
Theoretical studies of jet stopping in strongly-coupled QCD-like plasmas have used gauge-gravity duality to find that the maximum stopping distance scales like E^{1/3} for large jet energies E. In recent work studying jets that are created by finite-size sources in the gauge theory, we found an additional scale: the typical (as opposed to maximum) jet stopping distance scales like (EL)^{1/4}, where L is the size of the space-time region where the jet is created. In this paper, we show that the results of our previous, somewhat involved computation in the gravity dual, and the (EL)^{1/4} scale in particular, can be very easily reproduced and understood in terms of the distance that high-energy particles travel in AdS_5-Schwarzschild space before falling into the black brane. We also investigate how stopping distances depend on the conformal dimension of the source operator used to create the jet.
Gauge/String-Gravity Duality and Froissart Bound
Kyungsik Kang
2004-10-16T23:59:59.000Z
The gauge/string-gravity duality correspondence opened renewed hope and possibility to address some of the fundamental and non-perturbative QCD problems in particle physics, such as hadron spectrum and Regge behavior of the scattering amplitude at high energies. One of the most fundamental and long-standing problem is the high energy behavior of total cross-sections. According to a series of exhaustive tests by the COMPETE group, (1). total cross-sections have a universal Heisenberg behavior in energy corresponding to the maximal energy behavior allowed by the Froissart bound, i.e., $A + B ln^2 (s/s_0)$ with $B \\sim 0.32 mb$ and $s_0 \\sim 34.41 GeV^2$ for all reactions, and (2). the factorization relation among $\\sigma_{pp, even}, \\sigma_{\\gamma p}, and \\sigma_{\\gamma \\gamma}$ is well satisfied by experiments. I discuss the recent interesting application of the gauge/string-gravity duality of $AdS/CFT$ correspondence with a deformed background metric so as to break the conformal symmetry that can lead to the Heisenberg behavior of rising total cross-sections, and present some preliminary results on the high energy QCD from Planckian scattering in $AdS$ and black-hole production.
Study of the thermal abelian monopoles with proper gauge fixing
V. G. Bornyakov; V. V. Braguta
2011-10-28T23:59:59.000Z
The properties of the thermal abelian monopoles are studied in the deconfinement phase of the SU(2) gluodynamics. To remove effects of Gribov copies the simulated annealing algorithm is applied to fix the maximally abelian gauge. Computing the density of the thermal abelian monopoles in the temperature range between 1.5T_c and 6.9T_c we show, by comparison with earlier results, that the Gribov copies effects might be as high as 20% making proper gauge fixing mandatory. We find that in the infinite temperature limit the monopole density converges to its value in 3-dimensional theory. To study the interaction between monopoles we calculate the monopole-monopole and monopole-antimonopole correlators at different temperatures in the region (1.5T_c, 6.9T_c). Using the result of this study we determine the screening mass, monopole-monopole coupling constant, monopole size and monopole mass. In addition we check the continuum limit of our results.
Gauge field, strings, solitons, anomalies and the speed of life
Antti J. Niemi
2014-07-05T23:59:59.000Z
It's been said that "mathematics is biology's next microscope, only better; biology is mathematics' next physics, only better". Here we aim for something even better. We try to combine mathematical physics and biology into a picoscope of life. For this we merge techniques which have been introduced and developed in modern mathematical physics, largely by Ludvig Faddeev to describe objects such as solitons and Higgs and to explain phenomena such as anomalies in gauge fields. We propose a synthesis that can help to resolve the protein folding problem, one of the most important conundrums in all of science. We apply the concept of gauge invariance to scrutinize the extrinsic geometry of strings in three dimensional space. We evoke general principles of symmetry in combination with Wilsonian universality and derive an essentially unique Landau-Ginzburg energy that describes the dynamics of a generic string-like configuration in the far infrared. We observe that the energy supports topological solitons, that pertain to an anomaly in the manner how a string is framed around its inflection points. We explain how the solitons operate as modular building blocks from which folded proteins are composed. We describe crystallographic protein structures by multi-solitons with experimental precision, and investigate the non-equilibrium dynamics of proteins under varying temperature. We simulate the folding process of a protein at in vivo speed and with close to pico-scale accuracy using a standard laptop computer: With pico-biology as mathematical physics' next pursuit, things can only get better.
Quiver Gauge Models in F-Theory on Local Tetrahedron
Lalla Btissam Drissi; Leila Medari; El Hassan Saidi
2009-08-03T23:59:59.000Z
We study a class of 4D $\\mathcal{N}=1$ supersymmetric GUT- type models in the framework of the Beasley-Heckman-Vafa theory. We first review general results on MSSM and supersymmetric GUT; and we describe useful tools on 4D quiver gauge theories in F- theory set up. Then we study the effective supersymmetric gauge theory in the 7-brane wrapping 4-cycles in F-theory on local elliptic CY4s based on a complex tetrahedral surface $\\mathcal{T}$ and its blown ups $\\mathcal{T}_{n}$. The complex 2d geometries $\\mathcal{T}$ and $\\mathcal{T}_{n}$ are \\emph{non planar} projective surfaces that extend the projective plane $\\mathbb{P}^{2}$ and the del Pezzos. Using the power of toric geometry encoding the toric data of the base of the local CY4, we build a class of \\emph{4D} $\\mathcal{N}=1$ non minimal GUT- type models based on $\\mathcal{T}$ and $\\mathcal{T}_{n}$. An explicit construction is given for the SU$(5) $ GUT-type model.
2015-01-01T23:59:59.000Z
application of water (irrigation or rain) tends to breakrain or irrigation) stops because gravitational waterof rain gauges in monitoring the volumes of water delivered
Vortex free energies in SO(3) and SU(2) lattice gauge theory
Philippe de Forcrand; Oliver Jahn
2002-09-04T23:59:59.000Z
Lattice gauge theories with gauge groups SO(3) and SU(2) are compared. The free energy of electric twist, an order parameter for the confinement-deconfinement transition which does not rely on centre-symmetry breaking, is measured in both theories. The results are used to calibrate the scale in SO(3).
Free energy for parameterized Polyakov loops in SU(2) and SU(3) lattice gauge theory
Rossak, Wilhelm R.
Free energy for parameterized Polyakov loops in SU(2) and SU(3) lattice gauge theory [arXiv:1205 by analyzing the free energy of static quarks in pure SU(2) and SU(3) lattice gauge theory. The Polyakov loop P is introduced as a parameterized source for the quarks. Calculation of the free energy F as a function
Realization of the Noncommutative Seiberg-Witten Gauge Theory by Fields in Phase Space
R. G. G. Amorim; F. C. Khanna; A. P. C. Malbouisson; J. M. C. Malbouisson; A. E. Santana
2014-02-06T23:59:59.000Z
Representations of the Poincar\\'{e} symmetry are studied by using a Hilbert space with a phase space content. The states are described by wave functions ( quasi amplitudes of probability) associated with Wigner functions (quasi probability density). The gauge symmetry analysis provides a realization of the Seiberg-Witten gauge theory for noncommutative fields.
Exact solution to the Seiberg-Witten equation of noncommutative gauge theory
Okawa, Yuji; Ooguri, Hirosi
2001-08-15T23:59:59.000Z
We derive an exact expression for the Seiberg-Witten map of noncommutative gauge theory. It is found by studying the coupling of the gauge field to the Ramond-Ramond potentials in string theory. Our result also proves the earlier conjecture by Liu.
A new formulation of higher parallel transport in higher gauge theory
Emanuele Soncini; Roberto Zucchini
2014-10-03T23:59:59.000Z
In this technical paper, we present a new formulation of higher parallel transport in strict higher gauge theory required for the rigorous construction of Wilson lines and surfaces. Our approach is based on an original notion of Lie crossed module cocycle and cocycle 1- and 2-gauge transformation with a non standard double category theoretic interpretation. We show its equivalence to earlier formulations.
Acceptance Test Report for the 241-AN-107 Enraf Advanced Technology Gauges
Dowell, J.L.; Enderlin, V.R.
1995-06-01T23:59:59.000Z
This Acceptance Test Report covers the results of the execution of the Acceptance Test Procedure for the 241-AN-107 Enraf Advanced Technology Gauges. The test verified the proper operation of the gauges to measure waste density and level in the 241-AN-107 tank.
Gauge-Invariant Perturbations in Hybrid Quantum Cosmology
Gomar, Laura Castelló; Marugán, Guillermo A Mena
2015-01-01T23:59:59.000Z
We consider cosmological perturbations around homogeneous and isotropic spacetimes minimally coupled to a scalar field and present a formulation which is designed to preserve covariance. We truncate the action at quadratic perturbative order and particularize our analysis to flat compact spatial sections and a field potential given by a mass term, although the formalism can be extended to other topologies and potentials. The perturbations are described in terms of Mukhanov-Sasaki gauge invariants, linear perturbative constraints, and variables canonically conjugate to them. This set is completed into a canonical one for the entire system, including the homogeneous degrees of freedom. We find the global Hamiltonian constraint of the model, in which the contribution of the homogeneous sector is corrected with a term quadratic in the perturbations, that can be identified as the Mukhanov-Sasaki Hamiltonian in our formulation. We then adopt a hybrid approach to quantize the model, combining a quantum representatio...
M-Theory and Maximally Supersymmetric Gauge Theories
Neil Lambert
2012-05-21T23:59:59.000Z
In this informal review for non-specalists we discuss the construction of maximally supersymmetric gauge theories that arise on the worldvolumes branes in String Theory and M-Theory. Particular focus is made on the relatively recent construction of M2-brane worldvolume theories. In a formal sense, the existence of these quantum field theories can be viewed as predictions of M-Theory. Their construction is therefore a reinforcement of the ideas underlying String Theory and M-Theory. We also briefly discuss the six-dimensional conformal field theory that is expected to arise on M5-branes. The construction of this theory is not only an important open problem for M-Theory but also a significant challenge to our current understanding of quantum field theory more generally.
Testing Topology Conserving Gauge Actions for Lattice QCD
K. -i. Nagai; K. Jansen; W. Bietenholz; L. Scorzato; S. Necco; S. Shcheredin
2005-09-29T23:59:59.000Z
We explore gauge actions for lattice QCD, which are constructed such that the occurrence of small plaquette values is strongly suppressed. Such actions originate from the admissibility condition in order to conserve the topological charge. The suppression of small plaquette values is expected to be advantageous for numerical studies in the $\\epsilon$-regime and also for simulations with dynamical quarks. Performing simulations at a lattice spacing of about 0.1 fm, we present numerical results for the static potential, the physical scale $r_0$, the stability of the topological charge history, the condition number of the kernel of the overlap operator and the acceptance rate against the step size in the local HMC algorithm.
Noncommutative SO(2,3) gauge theory and noncommutative gravity
Marija Dimitrijevic; Voja Radovanovic
2014-07-30T23:59:59.000Z
In this paper noncommutative gravity is constructed as a gauge theory of the noncommutative SO(2,3) group, while the noncommutativity is canonical (constant). The Seiberg-Witten map is used to express noncommutative fields in terms of the corresponding commutative fields. The commutative limit of the model is the Einstein-Hilbert action with the cosmological constant term and the topological Gauss-Bonnet term. We calculate the second order correction to this model and obtain terms that are of zeroth to fourth power in the curvature tensor and torsion. Trying to relate our results with $f(R)$ and $f(T)$ models, we analyze different limits of our model. In the limit of big cosmological constant and vanishing torsion we obtain a $x$-dependent correction to the cosmological constant, i.e. noncommutativity leads to a $x$-dependent cosmological constant. We also discuss the limit of small cosmological constant and vanishing torsion and the teleparallel limit.
A nanocrystal strain gauge for luminescence detection of mechanical forces
Choi, Charina; Koski, Kristie; Olson, Andrew; Alivisatos, Paul
2010-07-26T23:59:59.000Z
Local microscale stresses play a crucial role in inhomogeneous mechanical processes from cell motility to material failure. However, it remains difficult to spatially resolve stress at these small length scales. While contact-probe and non-contact based techniques have been used to quantify local mechanical behavior in specific systems with high stiffness or stress and spatial resolution, these methods cannot be used to study a majority of micromechanical systems due to spectroscopic and geometrical constraints. We present here the design and implementation of a luminescent nanocrystal strain gauge, the CdSe/CdS core/shell tetrapod. The tetrapod can be incorporated into many materials, yielding a local stress measurement through optical fluorescence spectroscopy of the electronically confined CdSe core states. The stress response of the tetrapod is calibrated and utilized to study mechanical behavior in single polymer fibers. We expect that tetrapods can be used to investigate local stresses in many other mechanical systems.
SU(N) Gauge Theories Near $T_c$
B. Lucini; M. Teper; U. Wenger
2003-09-02T23:59:59.000Z
We study the deconfinement phase transition in SU(N) gauge theories for $N$=2,3,4,6,8. The transition is first order for $N \\ge 3$, with the strength increasing as $N$ increases. We extrapolate $T_c/\\sqrt{\\sigma}$ to the continuum limit for each $N$, and observe a rapid approach to the large $N$ limit. As $N$ increases the phase transition becomes clear-cut on smaller spatial volumes, indicating the absence of (non-singular) finite volume corrections at $N=\\infty$ -- reminiscent of large $N$ reduction. The observed rapid increase of the inter-phase surface tension with $N$ may indicate that for $N=\\infty$ the deconfinement transition cannot, in practise, occur.
Glueball Wave Functions in U(1) Lattice Gauge Theory
Mushtaq Loan; Yi Ying
2006-06-26T23:59:59.000Z
Standard Monte Carlo simulations have been performed for 3-dimensional U(1) lattice gauge model on improved lattices to measure the wavefunction and size of the scalar and the tensor glueballs. Our results show the radii of ~ 0.60 and ~ 1.12 in the units of string tension, or ~0.28 and ~0.52 fm, for the scalar and tensor glueballs, respectively. At finite temperature we see clear evidence of the deconfined phase, and the transition appears to be similar to that of the two-dimensional XY model as expected from universality arguments. Preliminary results show no significant changes in the glueball wave functions and the masses in the deconfined phase.
On jet quenching parameters in strongly coupled non-conformal gauge theories
Alex Buchel
2006-08-02T23:59:59.000Z
Recently Liu, Rajagopal and Wiedemann (LRW) [hep-ph/0605178] proposed a first principle, nonperturbative quantum field theoretic definition of ``jet quenching parameter'' \\hat{q} used in models of medium-induced radiative parton energy loss in nucleus-nucleus collisions at RHIC. Relating \\hat{q} to a short-distance behavior of a certain light-like Wilson loop, they used gauge theory-string theory correspondence to evaluate \\hat{q} for the strongly coupled N=4 SU(N_c) gauge theory plasma. We generalize analysis of LRW to strongly coupled non-conformal gauge theory plasma. We find that a jet quenching parameter is gauge theory specific (not universal). Furthermore, it appears it's value increases as the number of effective adjoint degrees of freedom of a gauge theory plasma increases.
Towards a manifestly gauge invariant and universal calculus for Yang-Mills theory
Arnone, S; Morris, T R; Arnone, Stefano; Gatti, Antonio; Morris, Tim R.
2002-01-01T23:59:59.000Z
A manifestly gauge invariant exact renormalization group for pure SU(N) Yang-Mills theory is proposed, along with the necessary gauge invariant regularisation which implements the effective cutoff. The latter is naturally incorporated by embedding the theory into a spontaneously broken SU(N|N) super-gauge theory, which guarantees finiteness to all orders in perturbation theory. The effective action, from which one extracts the physics, can be computed whilst manifestly preserving gauge invariance at each and every step. As an example, we give an elegant computation of the one-loop SU(N) Yang-Mills beta function, for the first time at finite N without any gauge fixing or ghosts. It is also completely independent of the details put in by hand, e.g. the choice of covariantisation and the cutoff profile, and, therefore, guides us to a procedure for streamlined calculations.
Towards a manifestly gauge invariant and universal calculus for Yang-Mills theory
Stefano Arnone; Antonio Gatti; Tim R. Morris
2002-09-16T23:59:59.000Z
A manifestly gauge invariant exact renormalization group for pure SU(N) Yang-Mills theory is proposed, along with the necessary gauge invariant regularisation which implements the effective cutoff. The latter is naturally incorporated by embedding the theory into a spontaneously broken SU(N|N) super-gauge theory, which guarantees finiteness to all orders in perturbation theory. The effective action, from which one extracts the physics, can be computed whilst manifestly preserving gauge invariance at each and every step. As an example, we give an elegant computation of the one-loop SU(N) Yang-Mills beta function, for the first time at finite N without any gauge fixing or ghosts. It is also completely independent of the details put in by hand, e.g. the choice of covariantisation and the cutoff profile, and, therefore, guides us to a procedure for streamlined calculations.
Six-dimensional (1,0) superconformal models and higher gauge theory
Palmer, Sam; Sämann, Christian [Maxwell Institute for Mathematical Sciences, Department of Mathematics, Heriot-Watt University, Colin Maclaurin Building, Riccarton, Edinburgh EH14 4AS (United Kingdom)] [Maxwell Institute for Mathematical Sciences, Department of Mathematics, Heriot-Watt University, Colin Maclaurin Building, Riccarton, Edinburgh EH14 4AS (United Kingdom)
2013-11-15T23:59:59.000Z
We analyze the gauge structure of a recently proposed superconformal field theory in six dimensions. We find that this structure amounts to a weak Courant-Dorfman algebra, which, in turn, can be interpreted as a strong homotopy Lie algebra. This suggests that the superconformal field theory is closely related to higher gauge theory, describing the parallel transport of extended objects. Indeed we find that, under certain restrictions, the field content and gauge transformations reduce to those of higher gauge theory. We also present a number of interesting examples of admissible gauge structures such as the structure Lie 2-algebra of an abelian gerbe, differential crossed modules, the 3-algebras of M2-brane models, and string Lie 2-algebras.
PRODUCTION PROCESS MONITORING OF MULTILAYERED MATERIALS USING TIME-DOMAIN TERAHERTZ GAUGES
Zimdars, David; Duling, Irl; Fichter, Greg; White, Jeffrey [Picometrix LLC, 2925 Boardwalk Dr., Ann Arbor, MI 48104 (United States)
2010-02-22T23:59:59.000Z
The results of both a laboratory and factory trial of a time-domain terahertz (TD-THz) multi-layer gauge for on-line process monitoring are presented. The TD-THz gauge is demonstrated on a two layer laminated plastic insulation material. The TD-THz gauge simultaneously measured the total and the individual layer thicknesses. Measurements were made while transversely scanning across a 12 foot wide sheet extruded at high speed in a factory environment. The results were analyzed for precision, accuracy, and repeatability; and demonstrated that the TD-THz gauge performed in an equivalent or superior manner to existing ionizing radiation gauges (which measure only one layer). Many dielectric materials (e.g., plastic, rubber, paper, paint) are transparent to THz pulses, and the measurement of a wide range of samples is possible.
Wen, Xiao-Gang
The standard model is a chiral gauge theory where the gauge fields couple to the right-hand and the left-hand fermions differently. The standard model is defined perturbatively and describes all elementary particles (except ...
ARM - Campaign Instrument - rain
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article) | SciTech Connect JournalgovInstrumentsgustprobe-airbudapest Comments? We would love togovInstrumentsradon Comments?
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article) | SciTech Connect JournalgovInstrumentsgustprobe-airbudapesttotdn
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article) | SciTechDatastreamsmpl Documentation Data QualityDatastreamsncepgfssfcDatastreamspgs
Fay, James A.
1983-01-01T23:59:59.000Z
High concentrations of sulfuric and nitric acid in raTn fn the northeastern USA are caused by the large scale combustion of fossil fuels within this region. Average precipitation acidity is pH 4.2, but spatial and temporal ...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article) |govInstrumentsmfrirt Documentation ARM Data Discovery Browse DatagovInstrumentspgs DocumentationgovInstrumentsrain
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5(Million Cubic Feet) Oregon (Including Vehicle Fuel) (Million CubicRefinersUpcoming ReleaseSheldon Wolff, 1973 TheHowAminoMechanical engineers work
Supercinski, Danielle
2006-01-01T23:59:59.000Z
used in the early 1900s, is becoming one such option. The Texas Water Resources Institute (TWRI) and Texas Cooperative Extension, working with several partners, are planning and constructing rainwater harvesting demonstrations in West Texas... to educate the public about its potential as an alternative and inexpensive source of high-quality water. Most rainwater harvesting systems in the past were for personal use, but some businesses, industries and public institutions are beginning to use...
Columbia University
Volume 116B, number 4 PHYSICSLETTERS 14 October 1982 CHARGE DEFINITION IN NON-ABEL[AN GAUGE THEORIES ~ L.F. ABBOTT and S. DESER Brandeis University, Waltham, MA 02254, USA Received 9 June 1982 Conserved gauge-invariant electric and magnetic charges are defined for non-abelian gauge theories in terms
Damiano Anselmi
2015-01-28T23:59:59.000Z
We prove the Adler-Bardeen theorem in a large class of general gauge theories, including nonrenormalizable ones. We assume that the gauge symmetries are general covariance, local Lorentz symmetry and Abelian and non-Abelian Yang-Mills symmetries, and that the local functionals of vanishing ghost number satisfy a variant of the Kluberg-Stern--Zuber conjecture. We show that if the gauge anomalies are trivial at one loop, for every truncation of the theory there exists a subtraction scheme where they manifestly vanish to all orders, within the truncation. Outside the truncation the cancellation of gauge anomalies can be enforced by fine-tuning local counterterms. The framework of the proof is worked out by combining a recently formulated chiral dimensional regularization with a gauge invariant higher-derivative regularization. If the higher-derivative regularizing terms are placed well beyond the truncation, and the energy scale $\\Lambda$ associated with them is kept fixed, the theory is super-renormalizable and has the property that, once the gauge anomalies are cancelled at one loop, they manifestly vanish from two loops onwards by simple power counting. When the $\\Lambda$ divergences are subtracted away and $\\Lambda$ is sent to infinity, the anomaly cancellation survives in a manifest form within the truncation and in a nonmanifest form outside. The standard model coupled to quantum gravity satisfies all the assumptions, so it is free of gauge anomalies to all orders.
Justification of the complex Langevin method with the gauge cooling procedure
Keitaro Nagata; Jun Nishimura; Shinji Shimasaki
2015-09-18T23:59:59.000Z
Recently there has been remarkable progress in the complex Langevin method, which aims at solving the complex action problem by complexifying the dynamical variables in the original path integral. In particular, a new technique called the gauge cooling was introduced and the full QCD simulation at finite density has been made possible in the high temperature (deconfined) phase or with heavy quarks. Here we provide a rigorous justification of the complex Langevin method including the gauge cooling procedure. We first show that the gauge cooling can be formulated as an extra term in the complex Langevin equation involving a gauge transformation parameter, which is chosen appropriately as a function of the configuration before cooling. The probability distribution of the complexified dynamical variables is modified by this extra term. However, this modification is shown not to affect the Fokker-Planck equation for the corresponding complex weight as far as observables are restricted to gauge invariant ones. Thus we demonstrate explicitly that the gauge cooling can be used as a viable technique to satisfy the convergence conditions for the complex Langevin method. We also discuss the "gauge cooling" in 0-dimensional systems such as vector models or matrix models.
The cost of gauge coupling unification in the SU(5) model at three loops
L. Mihaila
2013-05-14T23:59:59.000Z
The non-supersymmetric SU(5) model can accommodate heavy neutrinos and gauge coupling unification when augmented with an adjoint fermionic multiplet 24_F. Among the most important phenomenological implications of the model is the prediction of light fermions and scalars, charged under the SU(2) gauge group, in the reach of the Large Hadron Collider (LHC). In this talk, we report on the recent calculation of the correlation function between the mass scale of the new electroweak multiplets and the gauge coupling unification scale at three loop accuracy.
Asymptotic safety and the gauged SU(N) nonlinear {sigma} model
Fabbrichesi, M. [INFN, Sezione di Trieste (Italy); Percacci, R.; Tonero, A.; Zanusso, O. [Scuola Internazionale Superiore di Studi Avanzati via Bonomea 265, 34136 Trieste (Italy); INFN, Sezione di Trieste (Italy)
2011-01-15T23:59:59.000Z
We study the beta functions of the leading, two-derivative terms of the left-gauged SU(N) nonlinear {sigma} model in d dimensions. In d>2, we find the usual Gaussian ultraviolet fixed point for the gauge coupling and an attractive non-Gaussian fixed point for the Goldstone boson coupling. The position of the latter fixed point controls the chiral expansion, unitarity and the strength of the tree-level Goldstone boson scattering amplitudes. For large N the model is weakly coupled, unitary at all energies and well described by the lowest order of chiral perturbation theory. Attention is paid to the gauge and scheme dependence of the results.
Quantum Space-Time and Noncommutative Gauge Field Theories
Sami Saxell
2009-09-17T23:59:59.000Z
The three original publications in this thesis encompass various aspects in the still developing area of noncommutative quantum field theory, ranging from fundamental concepts to model building. One of the key features of noncommutative space-time is the apparent loss of Lorentz invariance that has been addressed in different ways in the literature. One recently developed approach is to eliminate the Lorentz violating effects by integrating over the parameter of noncommutativity. Fundamental properties of such theories are investigated in this thesis. Another issue addressed is model building, which is difficult in the noncommutative setting due to severe restrictions on the possible gauge symmetries imposed by the noncommutativity of the space-time. Possible ways to relieve these restrictions are investigated and applied and a noncommutative version of the Minimal Supersymmetric Standard Model is presented. While putting the results obtained in the three original publications into their proper context, the introductory part of this thesis aims to provide an overview of the present situation in the field.
Hairy black holes in N=2 gauged supergravity
Faedo, Federico; Nozawa, Masato
2015-01-01T23:59:59.000Z
We construct black holes with scalar hair in a wide class of four-dimensional N=2 Fayet-Iliopoulos gauged supergravity theories that are characterized by a prepotential containing one free parameter. Considering the truncated model in which only a single real scalar survives, the theory is reduced to an Einstein-scalar system with a potential, which admits at most two AdS critical points and is expressed in terms of a real superpotential. Our solution is static, admits maximally symmetric horizons, asymptotically tends to AdS space corresponding to an extremum of the superpotential, but is disconnected from the Schwarzschild-AdS family. The condition under which the spacetime admits an event horizon is addressed for each horizon topology. It turns out that for hyperbolic horizons the black holes can be extremal. In this case, the near-horizon geometry is AdS_2 x H^2, where the scalar goes to the other, non-supersymmetric, critical point of the potential. Our solution displays fall-off behaviours different fro...
Thermodynamics of SU(3) Gauge Theory in 2 + 1 Dimensions
P. Bialas; L. Daniel; A. Morel; B. Petersson
2008-07-21T23:59:59.000Z
The pressure, and the energy and entropy densities are determined for the SU(3) gauge theory in $2 + 1$ dimensions from lattice Monte Carlo calculations in the interval $0.6 \\leq T/T_c \\leq 15$. The finite temperature lattices simulated have temporal extent $N_\\tau = 2, 4, 6$ and 8, and spatial volumes $N_S^2$ such that the aspect ratio is $N_S/N_\\tau = 8$. To obtain the thermodynamical quantities, we calculate the averages of the temporal plaquettes $P_\\tau$ and the spatial plaquettes $P_S$ on these lattices. We also need the zero temperature averages of the plaquettes $P_0$, calculated on symmetric lattices with $N_\\tau = N_S$. We discuss in detail the finite size ($N_S$-dependent) effects. These disappear exponentially. For the zero temperature lattices we find that the coefficient of $N_S$ in the exponent is of the order of the glueball mass. On the finite temperature lattices it lies between the two lowest screening masses. For the aspect ratio equal to eight, the systematic errors coming from the finite size effects are much smaller than our statistical errors. We argue that in the continuum limit, at high enough temperature, the pressure can be parametrized by the very simple formula $p=a-bT_c/T$ where $a$ and $b$ are two constants. Using the thermodynamical identities for a large homogeneous system, this parametrization then determines the other thermodynamical variables in the same temperature range.
CERN Winter School on Supergravity, Strings, and Gauge Theory 2010
None
2011-10-06T23:59:59.000Z
The CERN Winter School on Supergravity, Strings, and Gauge Theory is the analytic continuation of the yearly training school of the former EC-RTN string network "Constituents, Fundamental Forces and Symmetries of the Universe". The 2010 edition of the school is supported and organized by the CERN Theory Divison, and will take place from Monday January 25 to Friday January 29, at CERN. As its predecessors, this school is meant primarily for training of doctoral students and young postdoctoral researchers in recent developments in theoretical high-energy physics and string theory. The programme of the school will consist of five series of pedagogical lectures, complemented by tutorial discussion sessions in the afternoons. Previous schools in this series were organized in 2005 at SISSA in Trieste, and in 2006, 2007, 2008, and 2009 at CERN, Geneva. Other similar schools have been organized in the past by the former related RTN network "The Quantum Structure of Spacetime and the Geometric Nature of Fundamental Interactions". This edition of the school is not funded by the European Union. The school is funded by the CERN Theory Division, and the Arnold Sommerfeld Center at Ludwig-Maximilians University of Munich. Scientific committee: M. Gaberdiel, D. Luest, A. Sevrin, J. Simon, K. Stelle, S. Theisen, A. Uranga, A. Van Proeyen, E. Verlinde Local organizers: A. Uranga, J. Walcher
Gauge independence of the bubble nucleation rate in theories with radiative symmetry breaking
Metaxas, D.; Weinberg, E.J. [Department of Physics, Columbia University, New York, New York 10027 (United States)] [Department of Physics, Columbia University, New York, New York 10027 (United States)
1996-01-01T23:59:59.000Z
In field theories where a metastable false vacuum state arises as a result of radiative corrections, the calculation of the rate of false vacuum decay by bubble nucleation depends on the effective potential and the other functions that appear in the derivative expansion of the effective action. Beginning with the Nielsen identity, we derive a series of identities that govern the gauge dependence of these functions. Using these, we show, to leading nontrivial order, that, even though these functions are individually gauge dependent, one obtains a gauge-independent result for the bubble nucleation rate. Our formal arguments are complemented by explicit calculations for scalar electrodynamics in a class of {ital R}{sub {xi}} gauges. {copyright} {ital 1996 The American Physical Society.}
Interacting gauge fields and the zero-energy eigenstates in two dimensions
Tsunehiro Kobayashi
2005-03-07T23:59:59.000Z
Gauge fields are formulated in terms of the zero-energy eigenstates of 2-dimensional Schr$\\ddot {\\rm o}$dinger equations with central potentials $V_a(\\rho)=-a^2g_a\\rho^{2(a-1)}$ ($a\
Kaizen events implementation for cycle time reduction in gauge production line
Liu, Ren, M. Eng. Massachusetts Institute of Technology
2010-01-01T23:59:59.000Z
This thesis describes the implementation of three Kaizen events designed to improve efficiency on a gauge production line which consists of both semiconductor and mechanical equipment for manufacturing complex products ...
July 20, 2001; rev. August 16, 2001 General Covariance, Gauge Theories and the Kretschmann
1 July 20, 2001; rev. August 16, 2001 General Covariance, Gauge Theories and the Kretschmann of Parma, June 21-23, 2001, organized by Massimo Pauri. #12;2 1. Introduction Two views... When Einstein
Supersymmetric N=1 Spin(10) Gauge Theory with Two Spinors via a-Maximization
Teruhiko Kawano; Futoshi Yagi
2007-05-28T23:59:59.000Z
We give a detailed analysis of the superconformal fixed points of four-dimensional N=1 supersymmetric Spin(10) gauge theory with two spinors and vectors by using a-maximization procedure.
Building Technologies Program: Tax Deduction Qualified Software- EnergyGauge Summit version 3.11
Broader source: Energy.gov [DOE]
Provides required documentation that EnergyGauge Summit version 3.11 meets Internal Revenue Code §179D, Notice 2006-52, dated June 2, 2006, for calculating commercial building energy and power cost savings.
Building Technologies Program: Tax Deduction Qualified Software- EnergyGauge Summit version 3.13
Broader source: Energy.gov [DOE]
Provides required documentation that EnergyGauge Summit version 3.13 meets Internal Revenue Code §179D, Notice 2006-52, dated June 2, 2006, for calculating commercial building energy and power cost savings.
Building Technologies Program: Tax Deduction Qualified Software- EnergyGauge Summit version 3.14
Broader source: Energy.gov [DOE]
Provides required documentation that EnergyGauge Summit version 3.14 meets Internal Revenue Code §179D, Notice 2006-52, dated June 2, 2006, for calculating commercial building energy and power cost savings.
Testing volume independence of large N gauge theories on the lattice
Antonio Gonzalez-Arroyo; Masanori Okawa
2014-11-12T23:59:59.000Z
For a pure SU(N) gauge theory on the lattice we test if the expectation values of small Wilson loops become volume independent in the large N limit.
Gauging the twisted Poincare symmetry as a noncommutative theory of gravitation
Chaichian, M.; Tureanu, A. [Department of Physics, University of Helsinki, P.O. Box 64, FIN-00014 Helsinki (Finland); Helsinki Institute of Physics, P.O. Box 64, FIN-00014 Helsinki (Finland); Oksanen, M. [Department of Physics, University of Helsinki, P.O. Box 64, FIN-00014 Helsinki (Finland); Zet, G. [Department of Physics, 'Gh. Asachi' Technical University, Bd. D. Mangeron 67, 700050 Iasi (Romania)
2009-02-15T23:59:59.000Z
Einstein's theory of general relativity was formulated as a gauge theory of Lorentz symmetry by Utiyama in 1956, while the Einstein-Cartan gravitational theory was formulated by Kibble in 1961 as the gauge theory of Poincare transformations. In this framework, we propose a formulation of the gravitational theory on canonical noncommutative space-time by covariantly gauging the twisted Poincare symmetry, in order to fulfil the requirement of covariance under the general coordinate transformations, an essential ingredient of the theory of general relativity. It appears that the twisted Poincare symmetry cannot be gauged by generalizing the Abelian twist to a covariant non-Abelian twist, nor by introducing a more general covariant twist element. The advantages of such a formulation as well as the related problems are discussed and possible ways out are outlined.
The Effective String of 3D Gauge Systems at the Deconfining Transition
M. Caselle; F. Gliozzi
1991-10-01T23:59:59.000Z
It is argued that the effective string of whatever 3D gauge system at the deconfining transition is universally described by the minimal $N=2$ extended superconformal theory at $c=1$. A universal value of the critical temperature is predicted.
Zutavern, Zachary Scott
2004-09-30T23:59:59.000Z
Historical attempts to measure forces in magnetic bearings have been unsuccessful as a result of relatively high uncertainties. Recent advances in the strain-gauge technology have provided a new method for measuring ...
Electric/magnetic duality for chiral gauge theories with anomaly cancellation
Jan De Rydt; Torsten T. Schmidt; Mario Trigiante; Antoine Van Proeyen; Marco Zagermann
2009-02-07T23:59:59.000Z
We show that 4D gauge theories with Green-Schwarz anomaly cancellation and possible generalized Chern-Simons terms admit a formulation that is manifestly covariant with respect to electric/magnetic duality transformations. This generalizes previous work on the symplectically covariant formulation of anomaly-free gauge theories as they typically occur in extended supergravity, and now also includes general theories with (pseudo-)anomalous gauge interactions as they may occur in global or local N=1 supersymmetry. This generalization is achieved by relaxing the linear constraint on the embedding tensor so as to allow for a symmetric 3-tensor related to electric and/or magnetic quantum anomalies in these theories. Apart from electric and magnetic gauge fields, the resulting Lagrangians also feature two-form fields and can accommodate various unusual duality frames as they often appear, e.g., in string compactifications with background fluxes.
T. P. Shestakova
2008-01-30T23:59:59.000Z
In "extended phase space" approach to quantum geometrodynamics numerical solutions to Schrodinger equation corresponding to various choice of gauge conditions are obtained for the simplest isotropic model. The "extended phase space" approach belongs to those appeared in the last decade in which, as a result of fixing a reference frame, the Wheeler - DeWitt static picture of the world is replaced by evolutionary quantum geometrodynamics. Some aspects of this approach were discussed at two previous PIRT meetings. We are interested in the part of the wave function depending on physical degrees of freedom. Three gauge conditions having a clear physical meaning are considered. They are the conformal time gauge, the gauge producing the appearance of Lambda-term in the Einstein equations, and the one covering the two previous cases as asymptotic limits. The interpretation and discussion of the obtained solutions is given.
EnergyGauge USA: A Residential Building Energy Simulation Design Tool
Fairey, P.; Vieira, R. K.; Parker, D. S.; Hanson, B.; Broman, P. A.; Grant, J. B.; Fuehrlein, B.; Gu, L.
2002-01-01T23:59:59.000Z
software have used simplified methods for calculation of residential building energy performance due to limitations on computing speed. However, EnergyGauge USA, takes advantage of current generation personal computers that perform an hourly annual computer...
EnergyGauge USA: A Residential Building Energy Simulation Design Tool
Fairey, P.; Vieira, R. K.; Parker, D. S.; Hanson, B.; Broman, P. A.; Grant, J. B.; Fuehrlein, B.; Gu, L.
2002-01-01T23:59:59.000Z
software have used simplified methods for calculation of residential building energy performance due to limitations on computing speed. However, EnergyGauge USA, takes advantage of current generation personal computers that perform an hourly annual computer...
ThePopularCrazeofSummer2014: ALSIceBucketChallenge
Hammack, Richard
of respondents actually completed the challenge despite it seeming to proliferate across everybody's Facebook is wonderful" but emphasized that "the actual dumping of ice on your head then nominating someone else to do
A Computational Analysis of Lower Bounds for Big Bucket ...
2012-02-13T23:59:59.000Z
give an extensive survey of both known and new methods, and also establish relationships between some ... These problems search for the production plan with the minimum total cost ... Dept. of Management Science, University of Strathclyde.
Fleet DNA Project Data Summary Report for Bucket Trucks
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article)41clothThe Bonneville Power AdministrationHawaiiEnergyFlorida July 9,Department of EnergyHouseFitNew Hansen 134 27 32
NASA/TM-1998-208419 Buckets: Aggregative, Intelligent Agents
Nelson, Michael L.
Space Information 7121 Standard Drive Hanover, MD 21076-1320 #12;National Aeronautics and Space Administration Standard Drive 5285 Port Royal Road Hanover, MD 21076-1320 Springfield, VA 22161-2171 (301) 621-0390 (703
A study of the troxler nuclear soil density and moisture gauges
Friedenwald, Robert Lane
1963-01-01T23:59:59.000Z
A STUDY OF THE TROXLER NUCLEAR SOIL DENSITY AND MOISTURE GAUGES A Thesis By Robert Lane Friedenwald Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE May 1963 Major Subject: Civil Engineering A STUDY OF THE TROXLER NUCLEAR SOIL DENSITY AND MOISTURE GAUGES A Thesis By Robert Lane Friedenwald Approved as to style and content by: (Chairma of Committee) (Hea of Department) May...
Running alpha(s) from Landau-gauge gluon and ghost correlations
A. Sternbeck; E. -M. Ilgenfritz; K. Maltman; M. Müller-Preussker; L. von Smekal; A. G. Williams
2007-10-16T23:59:59.000Z
We estimate the running coupling constant of the strong interactions within the nonperturbative framework of lattice QCD in Landau gauge. Our calculation is based on the ghost-gluon vertex which in the particular case of Landau gauge allows for a definition of alpha(s) in a MOM scheme solely in terms of the gluon and ghost dressing functions. As a first step we investigate the zero and two-flavour case and report here on preliminary results.
Grande Ronde Subbasin Gauging Station Operations, 2007-2008 Reporting Period.
Menton, R. Coby [Grande Ronde Model Watershed
2008-11-10T23:59:59.000Z
The Grande Ronde Basin (GRB) in Northeast Oregon is a moderately dry climate receiving between 10 and 20 inches of precipitation per year with surrounding mountains accumulating up to 100 inches. Irrigated agriculture is a major part of the economy with water being diverted or pumped from surface and ground sources from April through October. Several ESA listed species exist in the basin including Chinook, steelhead, and bulltrout. Agriculture and ESA (Endangered Species Act) listed aquatic species combined with a dry climate demonstrate the need for a network of stream gauges. The GRB covers over 5,000 square miles and includes several thousand miles of perennial flowing streams. This project is in place to operate 12 existing stream gauges in combination with USGS (4 gauges) and OWRD (one gauge) who, independent of this project, operate five additional gauges (Grande Ronde at Troy, Imnaha R. at Imnaha, Minam R. at Minam, Lookingglass Creek, and Upper Catherine Cr.) to characterizes flow in both the Grande Ronde and Imnaha subbasins. These gauges are intended to assist in irrigation water management, fisheries management, long term flow and trend analysis, TMDL and SB1010 water quality management plan effectiveness, subbasin plan implementation, and provide essential information regarding cumulative effects response to conservation in the GRB. Headwater characteristics, land management influence, and basin outlet data are all selectively collected in this network of 17 flow gauges. Prior to the 2007 water year there were three separate stream gauging programs with similar objectives, protocol, and funding sources in the GRB. Each of these programs for the past ten years has operated under separate administration consuming more time and administrative money than is necessary to accomplish stated objectives. By combining all programs into one project costs have been reduced, each funding source has one contract instead of three, and the same amount of work has been done accomplishing the same objectives. This objective has been continued and realized in the 2008 water year.
Renormalizability and Phenomenology of theta-expanded Noncommutative Gauge Field Theory
Josip Trampetic
2008-02-14T23:59:59.000Z
In this article we consider theta-expanded noncommutative gauge field theory, constructed at the first order in noncommutative parameter theta, as an effective, anomaly free theory, with one-loop renormalizable gauge sector. Related phenomenology with emphasis on the standard model forbidden decays, is discussed. Experimental possibilities of Z -> gamma gamma decay are analyzed and a firm bound to the scale of the noncommutativity parameter is set around few TeV's.
Is the $ISO(2,1)$ Gauge Gravity equivalent to the Metric Formulation?
Jin-Ho Cho; Hyuk-jae Lee
1996-08-21T23:59:59.000Z
The quantization of the gravitational Chern-Simons coefficient is investigated in the framework of $ISO(2,1)$ gauge gravity. Some paradoxes involved are cured. The resolution is largely based on the inequivalence of $ISO(2,1)$ gauge gravity and the metric formulation. Both the Lorentzian scheme and the Euclidean scheme lead to the coefficient quantization, which means that the induced spin is not quite exotic in this context.
Probing Extra Matter in Gauge Mediation Through the Lightest Higgs Boson Mass
Jason L. Evans; Masahiro Ibe; Tsutomu T. Yanagida
2011-08-17T23:59:59.000Z
We discuss the implications of the excesses in LHC Higgs boson searches on the gauge mediated supersymmetric standard model, for the mass range 120-140\\,GeV. We find that a relatively heavy lightest Higgs boson mass in this range can be reconciled with light SUSY particles, $m_{\\rm gluino}Higgs boson. We also find that the mass of this extra matter can be predicted rather precisely in gauge mediation for a given Higgs boson and gluino mass.
Coulomb and Landau Gauge Fixing in GPUs using CUDA and MILC
Cardoso, Nuno
2014-01-01T23:59:59.000Z
In this work, we present the GPU implementation of the overrelaxation and steepest descent method with Fourier acceleration methods for Laudau and Coulomb gauge fixing using CUDA for SU(N) with N>2. A multi-GPU implementation of the overrelaxation method is also presented using MPI and CUDA. The GPU performance was measured on BlueWaters and compared against the gauge fixing of the CPU MILC code.
Coulomb and Landau Gauge Fixing in GPUs using CUDA and MILC
Nuno Cardoso
2015-04-03T23:59:59.000Z
In this work, we present the GPU implementation of the overrelaxation and steepest descent method with Fourier acceleration methods for Laudau and Coulomb gauge fixing using CUDA for SU(N) with N>2. A multi-GPU implementation of the overrelaxation method is also presented using MPI and CUDA. The GPU performance was measured on BlueWaters and compared against the gauge fixing of the CPU MILC code.
Is it possible to accommodate massive photons in the framework of a gauge-invariant electrodynamics?
M. V. S. Fonseca; A. A. Vargas-Paredes
2010-05-19T23:59:59.000Z
The construction of an alternative electromagnetic theory that preserves Lorentz and gauge symmetries, is considered. We start off by building up Maxwell electrodynamics in (3+1)D from the assumption that the associated Lagrangian is a gauge-invariant functional that depends on the electron and photon fields and their first derivatives only. In this scenario, as well-known, it is not possible to set up a Lorentz invariant gauge theory containing a massive photon. We show nevertheless that there exist two radically different electrodynamics, namely, the Chern-Simons and the Podolsky formulations, in which this problem can be overcome. The former is only valid in odd space-time dimensions, while the latter requires the presence of higher-order derivatives of the gauge field in the Lagrangian. This theory, usually known as Podolsky electrodynamics, is simultaneously gauge and Lorentz invariant; in addition, it contains a massive photon. Therefore, a massive photon, unlike the popular belief, can be adequately accommodated within the context of a gauge-invariant electrodynamics.
On the dangers of using the growth equation on large scales in the Newtonian gauge
James B. Dent; Sourish Dutta
2009-02-20T23:59:59.000Z
We examine the accuracy of the growth equation $\\ddot{\\delta} + 2H\\dot{\\delta} - 4\\pi G\\rho\\delta = 0$, which is ubiquitous in the cosmological literature, in the context of the Newtonian gauge. By comparing the growth predicted by this equation to a numerical solution of the linearized Einstein equations in the $\\Lambda$CDM scenario, we show that while this equation is a reliable approximation on small scales ($k\\gtrsim $h Mpc$^{-1}$), it can be disastrously inaccurate ($\\sim 10^4% $) on larger scales in this gauge. We propose a modified version of the growth equation for the Newtonian gauge, which while preserving the simplicity of the original equation, provides considerably more accurate results. We examine the implications of the failure of the growth equation on a few recent studies, aimed at discriminating general relativity from modified gravity, which use this equation as a starting point. We show that while the results of these studies are valid on small scales, they are not reliable on large scales or high redshifts, if one works in the Newtonian gauge. Finally, we discuss the growth equation in the synchronous gauge and show that the corrections to the Poisson equation are exactly equivalent to the difference between the overdensities in the synchronous and Newtonian gauges.
Enraf Series 854 advanced technology gauge (ATG) acceptance test procedure. Revision 2
Barnes, G.A.
1995-01-30T23:59:59.000Z
This procedure checks that the shipment of the gauge to Hanford did not cause a failure. This procedure provides acceptance testing for Enraf Series 854 level gauges used to monitor levels in Hanford Waste Storage Tanks. The test will verify that the gauge functions according to the manufacturer`s instructions and specifications and is properly setup prior to being delivered to the tank farm area. Enraf-Nonius Series 854 level gauges are certified by Factory Mutual (FM) for National Fire Protectional Association (NFPA 70) hazardous Class 1, Division 1, Groups B, C, and D Locations. Its measuring principle is based on the detection of variations in the weight of a displacer suspended in the process fluid. The displacer is connected to a wire wounded on a precision measuring drum. A level change causes a change in the weight of the displacer which will be detected by the force transducer. Electronics within the gauge cause a servo motor to adjust the position of the displacer and compute the tank level based on the new position of the displacer drum. The gauge displays the level in decimal inches. An analog output signal transmits the level data for remote data processing.
Paris-Sud XI, Université de
of precipitation depths. Indeed, meteorological radar provides spatially distributed rainfall depths information (radars, hourly and daily rain gauges, satellite data, model freezing level heights, etc with rain gauge network. First, a methodology for automated identification and treatment of radar
A search for a new gauge boson A'
Jensen, Eric L. [William and Mary College
2013-08-01T23:59:59.000Z
In the Standard Model, gauge bosons mediate the strong, weak, and electromagnetic forces. New forces could have escaped detection only if their mediators are either heavier than order(TeV) or weakly coupled to charged matter. New vector bosons with small coupling {alpha}' arise naturally from a small kinetic mixing with the photon and have received considerable attention as an explanation of various dark matter related anomalies. Such particles can be produced in electron-nucleus fixed-target scattering and then decay to e{sup +}e{sup -} pairs. New light vector bosons and their associated forces are a common feature of Standard Model extensions, but existing constraints are remarkably sparse. The APEX experiment will search for a new vector boson A' with coupling {alpha}'/{alpha}{sub fs} > 6 × 10{sup -8} to electrons in the mass range 65MeV < mass A' < 550MeV. The experiment will study e{sup +}e{sup -} production off an electron beam incident on a high-Z target in Hall A at Jefferson Lab. The e{sup -} and e{sup +} will be detected in the High Resolution Spectrometers (HRSs). The invariant mass spectrum of the e{sup +}e{sup -} pairs will be scanned for a narrow resonance corresponding to the mass of the A'. A test run for the APEX experiment was held in the summer of 2010. Using the test run data, an A' search was performed in the mass range 175-250 MeV. The search found no evidence for an A' --> e{sup +}e{sup -} reaction, and set an upper limit of {alpha}'/{alpha}{sub fs} ~ 10{sup -6}.
Hairy black holes in N=2 gauged supergravity
Federico Faedo; Dietmar Klemm; Masato Nozawa
2015-05-22T23:59:59.000Z
We construct black holes with scalar hair in a wide class of four-dimensional N=2 Fayet-Iliopoulos gauged supergravity theories that are characterized by a prepotential containing one free parameter. Considering the truncated model in which only a single real scalar survives, the theory is reduced to an Einstein-scalar system with a potential, which admits at most two AdS critical points and is expressed in terms of a real superpotential. Our solution is static, admits maximally symmetric horizons, asymptotically tends to AdS space corresponding to an extremum of the superpotential, but is disconnected from the Schwarzschild-AdS family. The condition under which the spacetime admits an event horizon is addressed for each horizon topology. It turns out that for hyperbolic horizons the black holes can be extremal. In this case, the near-horizon geometry is AdS_2 x H^2, where the scalar goes to the other, non-supersymmetric, critical point of the potential. Our solution displays fall-off behaviours different from the standard one, due to the fact that the mass parameter $m^2=-2/\\ell^2$ at the supersymmetric vacuum lies in a characteristic range $m^2_{BF}\\le m^2\\le m^2_{\\rm BF}+\\ell^{-2}$ for which the slowly decaying scalar field is also normalizable. Nevertheless, we identify a well-defined mass for our spacetime, following the prescription of Hertog and Maeda. Quite remarkably, the product of all horizon areas is not given in terms of the asymptotic cosmological constant alone, as one would expect in absence of electromagnetic charges and angular momentum. Our solution shows qualitatively the same thermodynamic behaviour as the Schwarzschild-AdS black hole, but the entropy is always smaller for a given mass and AdS curvature radius. We also find that our spherical black holes are unstable against radial perturbations.
T. P. Shestakova
2005-12-09T23:59:59.000Z
In the earlier works on quantum geometrodynamics in extended phase space it has been argued that a wave function of the Universe should satisfy a Schrodinger equation. Its form, as well as a measure in Schrodinger scalar product, depends on a gauge condition (a chosen reference frame). It is known that the geometry of an appropriate Hilbert space is determined by introducing the scalar product, so the Hilbert space structure turns out to be in a large degree depending on a chosen gauge condition. In the present work we analyse this issue from the viewpoint of the path integral approach. We consider how the gauge condition changes as a result of gauge transformations. In this respect, three kinds of gauge transformations can be singled out: Firstly, there are residual gauge transformations, which do not change the gauge condition. The second kind is the transformations whose parameters can be related by homotopy. Then the change of gauge condition could be described by smoothly changing function. In particular, in this context time dependent gauges could be discussed. We also suggest that this kind of gauge transformations leads to a smooth changing of solutions to the Schrodinger equation. The third kind of the transformations includes those whose parameters belong to different homotopy classes. They are of the most interest from the viewpoint of changing the Hilbert space structure. In this case the gauge condition and the very form of the Schrodinger equation would change in discrete steps when we pass from a spacetime region with one gauge condition to another region with another gauge condition. In conclusion we discuss the relation between quantum gravity and fundamental problems of ordinary quantum mechanics.
Salafsky, N.; Dugelby, B.L.; Terborgh, J.W.
1992-04-01T23:59:59.000Z
Extractive reserves in tropical rain forests, in which only non-timber products are harvested, have been heralded by some conservationists as a means of maintaining biodiversity while providing income for local people. The study of extraction systems in Peten, Guatemala, and in West Kalimantan, Indonesia, leads to a more tempered conclusion, for while the Peten program was quite successful, the Kalimantan program was not. The study finds the success of an extractive reserve to be contingent on: (1) ecological conditions, and (2) socioeconomic and political factors. Although the study focuses on market-oriented extractive reserves, many of the issues discussed apply as well to other land uses such as the collection of non-timber forest products for household consumption or small-scale timber extraction.
Reimann, K.J.
1991-06-01T23:59:59.000Z
In a long-term program that began in 1984, limestone and marble briquettes have been exposed to both anthropogenic acid deposition and natural weathering of four field sites in the eastern United States. Similar tests began at an Ohio site in 1986. Effects of exposure on the briquettes and other materials at the sites are evaluated periodically by several federal agencies cooperating in the National Acid Precipitation Assessment Program (NAPAP). A primary contribution of Argonne National Laboratory to the NAPAP has been chemical analysis to determine changes in the samples caused by exposure to the environment. Wet chemical analysis was used to detect sulfates, nitrates, fluorides, chlorides, and a series of metal cations in sequential layers of stone removed from the briquettes after field exposure. Results from the first four years of the program indicate that rinsing by rain keeps skyward-facing stone relatively clean of reaction products, especially sulfate, the most abundant product. On groundward-facing samples, sulfate concentrations increased linearly with exposure time, and values were proportional to atmospheric SO{sub 2} concentrations at the site. Sulfate concentrations in groundward samples were much higher in limestone than in marble, because of the greater porosity of the limestone. A steep sulfate gradient was seen in both sample types from the surface to the interior. On skyward surfaces, material losses per rain event due to complete dissolution of accumulated sulfates were approximately equal to concentrations measured in runoff. Preexposed limestone samples had sulfate accumulations deep in their interiors, while fresh, unexposed limestone did not. No substantial changes in cation accumulations wee detected in either limestone or marble.
A Bicycle Built for Two: The Galilean and U(1) Gauge Invariance of the Schr\\"odinger Field
Colussi, V
2008-01-01T23:59:59.000Z
This paper undertakes a study of the nature of the force associated with the local U (1) gauge symmetry of a non-relativistic quantum particle. To ensure invariance under local U (1) symmetry, a matter field must couple to a gauge field. We show that such a gauge field necessarily satisfies the Maxwell equations, whether the matter field coupled to it is relativistic or non-relativistic. This result suggests that the structure of the Maxwell equations is determined by gauge symmetry rather than the symmetry transformation properties of space-time. In order to assess the validity of this notion, we examine the transformation properties of the coupled matter and gauge fields under Galilean transformations. Our main technical result is the Galilean invariance of the full equations of motion of the U (1) gauge field.
ENVIRONMETRICS Environmetrics (in press)
Li, Bo
) radar-reflectivity data and the corresponding rain gauge measurements. Simulation experiments with hydrological models. Since rain gauges physically measure the depth of rainfall at the points of measurement simulating large river basins. Compared to rain gauges, weather radars such as the Next generation weather
Boyer, Edmond
distributed rainfall depths that are potentially more informative than traditional ground rain gauge networks (radars, hourly and daily rain gauges, satellite data, model freezing level heights, ...) to obtain combination of radar data with hourly and daily rain gauge network. First, methodology for automated
L. D Lantsman
2012-05-01T23:59:59.000Z
The goal of this note is to give a description of Dirac variables in Abelian as well as non-Abelian gauge models in terms of gauge-invariant and Poincare-covariant states sweeping a Hilbert space ${\\cal H}_{\\rm vac}$. The next our conjecture concerns the spontaneous breakdown of the Abelian U(1) symmetry in the 'discrete' $U(1)\\to {\\bf Z}$ wise. We suppose that gauge charges are preserved in this case.
Quantum Simulations of Lattice Gauge Theories using Ultracold Atoms in Optical Lattices
Erez Zohar; J. Ignacio Cirac; Benni Reznik
2015-03-08T23:59:59.000Z
Can high energy physics can be simulated by low-energy, nonrelativistic, many-body systems, such as ultracold atoms? Such ultracold atomic systems lack the type of symmetries and dynamical properties of high energy physics models: in particular, they manifest neither local gauge invariance nor Lorentz invariance, which are crucial properties of the quantum field theories which are the building blocks of the standard model of elementary particles. However, it turns out, surprisingly, that there are ways to configure atomic system to manifest both local gauge invariance and Lorentz invariance. In particular, local gauge invariance can arise either as an effective, low energy, symmetry, or as an "exact" symmetry, following from the conservation laws in atomic interactions. Hence, one could hope that such quantum simulators may lead to new type of (table-top) experiments, that shall be used to study various QCD phenomena, as the con?nement of dynamical quarks, phase transitions, and other effects, which are inaccessible using the currently known computational methods. In this report, we review the Hamiltonian formulation of lattice gauge theories, and then describe our recent progress in constructing quantum simulation of Abelian and non-Abelian lattice gauge theories in 1 + 1 and 2 + 1 dimensions using ultracold atoms in optical lattices.
On Gauge Enhancement and Singular Limits in $G_2$ Compactifications of M-theory
Halverson, James
2015-01-01T23:59:59.000Z
We study the physics of singular limits of $G_2$ compactifications of M-theory, which are necessary to obtain a compactification with non-abelian gauge symmetry or massless charged particles. This is more difficult than for Calabi-Yau compactifications, due to the absence of calibrated two-cycles that would have allowed for direct control of W-boson masses as a function of moduli. Instead, we study the relationship between gauge enhancement and singular limits in $G_2$ moduli space where an associative or coassociative submanifold shrinks to zero size; this involves the physics of topological defects and sometimes gives indirect control over particle masses, even though they are not BPS. We show how a lemma of Joyce associates the class of a three-cycle to any $U(1)$ gauge theory in a smooth $G_2$ compactification. If there is an appropriate associative submanifold in this class then in the limit of nonabelian gauge symmetry it may be interpreted as a gauge theory worldvolume and provides the location of the ...
Finding the effective Polyakov line action for SU(3) gauge theories at finite chemical potential
Jeff Greensite; Kurt Langfeld
2014-05-22T23:59:59.000Z
Motivated by the sign problem, we calculate the effective Polyakov line action corresponding to certain SU(3) lattice gauge theories on a ${16^3 \\times 6}$ lattice via the "relative weights" method introduced in our previous articles. The calculation is carried out at $\\beta=5.6,5.7$ for the pure gauge theory, and at $\\beta=5.6$ for the gauge field coupled to a relatively light scalar particle. In the latter example we determine the effective theory also at finite chemical potential, and show how observables relevant to phase structure can be computed in the effective theory via mean field methods. In all cases a comparison of Polyakov line correlators in the effective theory and the underlying lattice gauge theory, computed numerically at zero chemical potential, shows accurate agreement down to correlator magnitudes of order $10^{-5}$. We also derive the effective Polyakov line action corresponding to a gauge theory with heavy quarks and large chemical potential, and apply mean field methods to extract observables.
H. B. Thacker
2010-01-24T23:59:59.000Z
Lattice Monte Carlo studies in SU(3) gauge theory have shown that the topological charge distribution in the vacuum is dominated by thin coherent membranes of codimension one arranged in a layered, alternating-sign sandwich. A similar lamination of topological charge occurs in the 2D $CP^{N-1}$ model. In holographic QCD, the observed topological charge sheets are naturally interpreted as $D6$ branes wrapped around an $S_4$.. With this interpretation, the laminated array of topological charge membranes observed on the lattice can be identified as a "tachyonic crystal", a regular, alternating-sign array of $D6$ and $\\bar{D6}$ branes that arises as the final state of the decay of a non-BPS $D7$ brane via the tachyonic mode of the attached string. In the gauge theory, the homogeneous, space-filling $D7$ brane represents the perturbative gauge vacuum, which is unstable toward lamination associated with a marginal tachyonic boundary perturbation $\\propto \\cos(X/\\sqrt{2\\alpha'})$. For the $CP^{N-1}$ model, the cutoff field theory can be cast as the low energy limit of an open string theory in background gauge and tachyon fields $A_{\\mu}(x)$ and $\\lambda(x)$. This allows a detailed comparison with large $N$ field theory results and provides strong support for the tachyonic crystal interpretation of the gauge theory vacuum.
Jürgen Struckmeier
2013-03-26T23:59:59.000Z
The Lagrangians and Hamiltonians of classical field theory require to comprise gauge fields in order to be form-invariant under local gauge transformations. These gauge fields have turned out to correctly describe pertaining elementary particle interactions. In this paper, this principle is extended to require additionly the form-invariance of a classical field theory Hamiltonian under variations of the space-time curvature emerging from the gauge fields. This approach is devised on the basis of the extended canonical transformation formalism of classical field theory which allows for transformations of the space-time metric in addition to transformations of the fields. Working out the Hamiltonian that is form-invariant under extended local gauge transformations, we can dismiss the conventional requirement for gauge bosons to be massless in order for them to preserve the local gauge invariance.The emerging equation of motion for the curvature scalar turns out to be compatible with the Einstein equation in the case of a static gauge field. The emerging equation of motion for the curvature scalar R turns out to be compatible with that from a Proca system in the case of a static gauge field.
A Superconnection for Riemannian Gravity as Spontaneously Broken SL(4,R) Gauge Theory
Yuval Ne'eman
1997-08-10T23:59:59.000Z
A superconnection is a supermatrix whose even part contains the gauge-potential one-forms of a local gauge group, while the odd parts contain the (0-form) Higgs fields; the combined grading is thus odd everywhere. We demonstrate that the simple supergroup ${\\bar P}(4,R)$ (rank=3) in Kac' classification (even subgroup $\\bar {SL}(4,R)$) prverline {SL}(4,R)$) provides for the most economical spontaneous breaking of $\\bar{SL}(4,R)$ as gauge group, leaving just local $\\bar{SO}(1,3)$ unbroken. As a result, post-Riemannian SKY gravity yields Einstein's theory as a low-energy (longer range) effective theory. The theory is renormalizable and may be unitary.
A Superconnection for Riemannian Gravity as Spontaneously Broken SL(4,R) Gauge Theory
Ne'eman, Yuval
1998-01-01T23:59:59.000Z
A superconnection is a supermatrix whose even part contains the gauge-potential one-forms of a local gauge group, while the odd parts contain the (0-form) Higgs fields; the combined grading is thus odd everywhere. We demonstrate that the simple supergroup ${\\bar P}(4,R)$ (rank=3) in Kac' classification (even subgroup $\\bar {SL}(4,R)$) prverline {SL}(4,R)$) provides for the most economical spontaneous breaking of $\\bar{SL}(4,R)$ as gauge group, leaving just local $\\bar{SO}(1,3)$ unbroken. As a result, post-Riemannian SKY gravity yields Einstein's theory as a low-energy (longer range) effective theory. The theory is renormalizable and may be unitary.