Norgren, D.U.
1982-09-23T23:59:59.000Z
A balanced braking system comprising a plurality of braking assemblies located about a member to be braked. Each of the braking assemblies consists of a spring biased piston of a first material fitted into a body of a different material which has a greater contraction upon cooling than the piston material. The piston is provided with a recessed head portion over which is positioned a diaphragm and forming a space therebetween to which is connected a pressurized fluid supply. The diaphragm is controlled by the fluid in the space to contact or withdraw from the member to be braked. A cooling means causes the body within which the piston is fitted to contract more than the piston, producing a tight shrink fit therebetween. The braking system is particularly applicable for selectively braking an arbor of an electron microscope which immobilizes, for example, a vertically adjustable low temperature specimen holder during observation. The system provides balanced braking forces which can be easily removed and re-established with minimal disturbance to arbor location.
Stevens, Samuel S. (Harriman, TN); Hodgson, Jeffrey W. (Lenoir City, TN)
2002-11-19T23:59:59.000Z
This invention relates to a force measuring system capable of measuring forces associated with vehicle braking and of evaluating braking performance. The disclosure concerns an invention which comprises a first row of linearly aligned plates, a force bearing surface extending beneath and beside the plates, vertically oriented links and horizontally oriented links connecting each plate to a force bearing surface, a force measuring device in each link, a transducer coupled to each force measuring device, and a computing device coupled to receive an output signal from the transducer indicative of measured force in each force measuring device. The present invention may be used for testing vehicle brake systems.
Combined hydraulic and regenerative braking system
Venkataperumal, Rama R. (Troy, MI); Mericle, Gerald E. (Mount Clemens, MI)
1981-06-02T23:59:59.000Z
A combined hydraulic and regenerative braking system and method for an electric vehicle, with the braking system being responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.
Speciation of Sb in airborne particulate matter, vehicle brake linings, and brake pad wear residues
Short, Daniel
Speciation of Sb in airborne particulate matter, vehicle brake linings, and brake pad wear residues: XAS XANES EXAFS Antimony Particulate matter Brake linings a b s t r a c t Insights into the speciation of Sb in samples of brake linings, brake pad wear residues, road dust, and atmospheric particulate
Hoppie, Lyle O. (Birmingham, MI)
1982-01-12T23:59:59.000Z
Disclosed are several embodiments of a regenerative braking device for an automotive vehicle. The device includes a plurality of rubber rollers (24, 26) mounted for rotation between an input shaft (14) connectable to the vehicle drivetrain and an output shaft (16) which is drivingly connected to the input shaft by a variable ratio transmission (20). When the transmission ratio is such that the input shaft rotates faster than the output shaft, the rubber rollers are torsionally stressed to accumulate energy, thereby slowing the vehicle. When the transmission ratio is such that the output shaft rotates faster than the input shaft, the rubber rollers are torsionally relaxed to deliver accumulated energy, thereby accelerating or driving the vehicle.
Variable ratio regenerative braking device
Hoppie, Lyle O. (Birmingham, MI)
1981-12-15T23:59:59.000Z
Disclosed is a regenerative braking device (10) for an automotive vehicle. The device includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (36) and an output shaft (42), clutches (38, 46) and brakes (40, 48) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. The rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft is clutched to the transmission while the brake on the output shaft is applied, and are torsionally relaxed to deliver energy to the vehicle when the output shaft is clutched to the transmission while the brake on the input shaft is applied. The transmission ratio is varied to control the rate of energy accumulation and delivery for a given rotational speed of the vehicle drivetrain.
Commercial Motor Vehicle Brake Assessment Tools
Commercial Motor Vehicle Brake Assessment Tools Commercial Motor Vehicle Roadside Technology to deceleration in g's Â Passing score: BE43.5 Â· Enforcement tool for only 3 years. Â· Based solely on brake Brake Research Â· CMVRTC research built on these enforcement tools Â Correlation Study Â Level-1 / PBBT
Brake blending strategy for a hybrid vehicle
Boberg, Evan S. (Hazel Park, MI)
2000-12-05T23:59:59.000Z
A hybrid electric powertrain system is provided including a transmission for driving a pair of wheels of a vehicle and a heat engine and an electric motor/generator coupled to the transmission. A friction brake system is provided for applying a braking torque to said vehicle. A controller unit generates control signals to the electric motor/generator and the friction brake system for controllably braking the vehicle in response to a drivers brake command. The controller unit determines and amount of regenerative torque available and compares this value to a determined amount of brake torque requested for determining the control signals to the electric motor/generator and the friction brake system.
Disturbance Control of the Hydraulic Brake in a Wind Turbine
Yang, Zhenyu
Disturbance Control of the Hydraulic Brake in a Wind Turbine Frank Jepsen, Anders SÃ¸borg brake in a wind turbine. Brake torque is determined by friction coefficient and clamp force; the latter brake is one1 of the two independent brake systems in a wind turbine. As a consequence of the gearing
Commercial Motor Vehicle Brake-Related Research
Commercial Motor Vehicle Brake-Related Research Commercial Motor Vehicle Roadside Technology Corridor Safety Technology Showcase October 14, 2010 Commercial Motor Vehicle Roadside Technology Corridor
Throttle And Brake Control Systems For Automatic Vehicle Following
Ioannou, P.; Xu, Z.
1994-01-01T23:59:59.000Z
and Brake Control Systems for Automatic Vehicle Following P.and Brake Control Systems for Automatic Vehicle Following *Transit Systems, Proceedings of 1977 Joint Automatic Control
Brake Defect Causation and Abatement Study (BDCAS)
on various lining materials for comparison study #12;Center for Transportation Analysis 2360 CherahalaBrake Defect Causation and Abatement Study (BDCAS) Oak Ridge National Laboratory managed by UT Based Brake Testers (PBBTs) part of the out-of- service criterion for commercial motor vehicles in 2007
TMV Technology Capabilities Brake Stroke Monitor
TMV Technology Capabilities Brake Stroke Monitor Brake monitoring systems are proactive maintenance This technology allows for CMV operators to have knowledge of their steer, drive, and tandem axle group weights setup is required. Current Safety/Enforcement Technologies EOBR (electronic on-board recorder) On
Contactless magnetic brake for automotive applications
Gay, Sebastien Emmanuel
2009-05-15T23:59:59.000Z
consumption due to power assistance, and requirement for anti-lock controls. To solve these problems, a contactless magnetic brake has been developed. This concept includes a novel flux-shunting structure to control the excitation flux generated by permanent...
An engine air-brake integration study
Mulchandani, Hiten
2011-01-01T23:59:59.000Z
The feasibility of operating an engine air-brake (EAB) integrated with a pylon duct bifurcation in a realistic aircraft engine environment has been analyzed. The EAB uses variable exit guide vanes downstream of a high ...
Method and apparatus for wind turbine braking
Barbu, Corneliu (Laguna Hills, CA); Teichmann, Ralph (Nishkayuna, NY); Avagliano, Aaron (Houston, TX); Kammer, Leonardo Cesar (Niskayuna, NY); Pierce, Kirk Gee (Simpsonville, SC); Pesetsky, David Samuel (Greenville, SC); Gauchel, Peter (Muenster, DE)
2009-02-10T23:59:59.000Z
A method for braking a wind turbine including at least one rotor blade coupled to a rotor. The method includes selectively controlling an angle of pitch of the at least one rotor blade with respect to a wind direction based on a design parameter of a component of the wind turbine to facilitate reducing a force induced into the wind turbine component as a result of braking.
Constraining the Braking Indices of Magnetars
Gao, Z F; Wang, N; Yuan, J P; Peng, Q H; Du, Y J
2015-01-01T23:59:59.000Z
Due to the lack of long term pulsed emission in quiescence and the strong timing noise, it is impossible to directly measure the braking index $n$ of a magnetar. Based on the estimated ages of their potentially associated supernova remnants (SNRs), we estimate the values of $n$ of nine magnetars with SNRs, and find that they cluster in a range of $1\\sim$41. Six magnetars have smaller braking indices of $13$ for other three magnetars are attributed to the decay of external braking torque, which might be caused by magnetic field decay. We estimate the possible wind luminosities for the magnetars with $13$ within the updated magneto-thermal evolution models. We point out that there could be some connections between the magnetar's anti-glitch event and its braking index, and the magnitude of $n$ should be taken into account when explaining the event. Although the constrained range of the magnetars' braking indices is tentative, our method provides an effective way to constrain the magnetars' braking indices if th...
Adaptive controller for regenerative and friction braking system
Davis, Roy I. (Ypsilanti, MI)
1990-01-01T23:59:59.000Z
A regenerative and friction braking system for a vehicle having one or more roadwheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerative brakes operatively connected with the roadwheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerative braking subsystems so that maximum brake torques sustainable by the roadwheels of the vehicle without skidding or slipping will not be exceeded.
Adaptive controller for regenerative and friction braking system
Davis, R.I.
1990-10-16T23:59:59.000Z
A regenerative and friction braking system for a vehicle having one or more road wheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerative brakes operatively connected with the road wheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerative braking subsystems so that maximum brake torques sustainable by the road wheels of the vehicle without skidding or slipping will not be exceeded. 8 figs.
A diagnostic system for air brakes in commercial vehicles
Coimbatore Subramanian, Shankar Ram
2007-09-17T23:59:59.000Z
This dissertation deals with the development of a model-based diagnostic system for air brake systems that are widely used in commercial vehicles, such as trucks, tractor-trailers, buses, etc. The performance of these brake ...
Electric vehicle regenerative antiskid braking and traction control system
Cikanek, S.R.
1995-09-12T23:59:59.000Z
An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydraulic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control. 10 figs.
Electric vehicle regenerative antiskid braking and traction control system
Cikanek, Susan R. (Wixom, MI)
1995-01-01T23:59:59.000Z
An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydrualic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control.
Nonlinear analysis of time series of vibration data from a friction brake: SSA, PCA, and MFDFA
Nikolay K. Vitanov; Norbert P. Hoffmann; Boris Wernitz
2014-10-23T23:59:59.000Z
We use the methodology of singular spectrum analysis (SSA), principal component analysis (PCA), and multi-fractal detrended fluctuation analysis (MFDFA), for investigating characteristics of vibration time series data from a friction brake. SSA and PCA are used to study the long time-scale characteristics of the time series. MFDFA is applied for investigating all time scales up to the smallest recorded one. It turns out that the majority of the long time-scale dynamics, that is presumably dominated by the structural dynamics of the brake system, is dominated by very few active dimensions only and can well be understood in terms of low dimensional chaotic attractors. The multi-fractal analysis shows that the fast dynamical processes originating in the friction interface are in turn truly multi-scale in nature.
The effect of friction on drum brakes
Huang, Y.M.; Shyr, J.S. [National Taiwan Univ. (China)
1995-12-31T23:59:59.000Z
The boundary element method (BEM) has been developed for a long period of time. Cruse and Wilson developed an isoparametric quadratic element. Rizzo, Cruse, Rizzo and Shippy, and Swedlow and cruse applied the method to various problems. It shows that the BEM can provide a very good analytical result in the linear problem and it can reduce time in preparation of numerical data. Watson and Newcomb pointed out that the pressure distribution on the contact surface of the brake drum and the lining plate do not vary significantly along the axis. The deflection can be reduced by an appropriate design of the web; therefore, two dimensional analysis with the BEM is used in this analysis. Based on the authors` knowledge, this is the first paper to analyze the drum brake by using the BEM. The assumptions are the brake drum to be a rigid body, perfect interface contact between the drum and the shoe, the constant friction coefficient of the friction material and the thermal effect to be neglected. The two dimensional equations are derived based on the Somigliana`s identity. Since there is no shape function and no need of the Jacobin for the coordinate transform, to integrate numerically is easier and to write a computer code is simpler for the constant value element than the second order element. The linear element is inappropriate to treat the comer problem. Using the linear elements or second order elements creates discontinuous phenomena along the irregular boundary. The common nodal point has different normal vector and boundary conditions. It is necessary to have an extra equation to provide a unique solution for the final linear equation. Using the constant value element can get rid of this problem. The effect of the friction on the pressure distribution at the friction interface is studied. The calculated results of the pressure distribution are compared with the available data. The mathematical model can be used as a design tool to predict the performance of drum brakes.
A diagnostic system for air brakes in commercial vehicles
Coimbatore Subramanian, Shankar Ram
2007-09-17T23:59:59.000Z
]. It is appropriate to point out that, in an appraisal of the future needs of the trucking industry [16], the authors, who represent a broad spectrum of the trucking industry, call for the development of improved methods of brake inspections. 6 B. Objectives... States railway industry, air brake systems were initially introduced during the nineteenth century. Before the introduction of the air brake system, railway cars were retarded mainly by mechanical means (for example, by levers, chains and other linkages...
Design, Modeling And Control Of Steering And Braking For An Urban Electric Vehicle
Maciua, Dragos
1996-01-01T23:59:59.000Z
Design, Modeling and Control of Steering and Braking for anDesign, Modeling and Control of Steering and Braking for anDesign, Modeling and Control of Steering and Braking for an
Measurement and control of brake pedal feel quality in automobile manufacturing
Cerilles, Jeffrey T. (Jeffrey Thomas)
2005-01-01T23:59:59.000Z
Customer perception of brake pedal feel quality, as related to the perception of the brake pedal feeling soft or mushy, depends on both the customer's subjective judgment of quality and the actual build quality of the brake ...
Pneumatic brake control for precision stopping of heavy-duty vehicles
Bu, Fanping; Tan, Han-Shue
2007-01-01T23:59:59.000Z
desirable that the automatic brake control system uses thesystems,” IEEE Transactions on Automatic Control, vol. 41,enables automatic control of the pneumatic brake system and
Pulsar Braking Index and Mass Accretion
P. D. Morley
1993-11-15T23:59:59.000Z
I show that the braking index, $N$, a fundamental pulsar experimental quantity, naturally differs from the canonical value of 3 by terms which involve mass accretion. Using the measured values of $N$ for PSR1509-58 and PSR0531+21, I determine that for constant density neutron stars their present mass accretion rates are $(3.10\\pm.51)\\times10^{-5}$ M year$^{-1}$ and $(9.946\\pm.089)\\times10^{-5}$ M year$^{-1}$ respectively, where M is the mass of each pulsar. Finally, I demonstrate that mass accretion removes the outstanding problem of the origin of the big glitches of the Vela Pulsar.
Do Si stars undergo any magnetic braking?
P. North
1998-02-23T23:59:59.000Z
The old question of rotational braking of Ap Si stars is revisited on the empirical side, taking advantage of the recent Hipparcos results. Field stars with various evolutionary states are considered, and it is shown that the loose correlation between their rotational period and their surface gravity is entirely compatible with conservation of angular momentum. No evidence is found for any loss of angular momentum on the Main Sequence, which confirms earlier results based on less reliable estimates of surface gravity. The importance of reliable, fundamental Teff determinations of Bp and Ap stars is emphasized.
Development of Diagnostic Algorithms for Air Brakes in Trucks
Dhar, Sandeep
2011-10-21T23:59:59.000Z
causes a reduction in the steady-state pressure in the brake chamber and an increase in the lag of the braking pressure response thereby increasing the stopping distance of the vehicle. Currently a presence of leak in the system is detected...
Braking system for use with an arbor of a microscope
Norgren, Duane U. (Orinda, CA)
1984-01-01T23:59:59.000Z
A balanced braking system comprising a plurality of braking assemblies located about a member to be braked. Each of the braking assemblies consists of a spring biased piston of a first material fitted into a body of a different material which has a greater contraction upon cooling than the piston material. The piston is provided with a recessed head portion over which is positioned a diaphragm and forming a space therebetween to which is connected a pressurized fluid supply. The diaphragm is controlled by the fluid in the space to contact or withdraw from the member to be braked. A cooling device causes the body within which the piston is fitted to contract more than the piston, producing a tight shrink fit therebetween. The braking system is particularly applicable for selectively braking an arbor of an electron microscope which immobilizes, for example, a vertically adjustable low temperature specimen holder during observation. The system provides balanced braking forces which can be easily removed and re-established with minimal disturbance to arbor location.
New Phase-coherent Measurements of Pulsar Braking Indices
Margaret A. Livingstone; Victoria M. Kaspi; Fotis P. Gavriil; Richard N. Manchester; E. V. Gotthelf; Lucien Kuiper
2007-02-07T23:59:59.000Z
Pulsar braking indices offer insight into the physics that underlies pulsar spin-down. Only five braking indices have been measured via phase-coherent timing; all measured values are less than 3, the value expected from magnetic dipole radiation. Here we present new measurements for three of the five pulsar braking indices, obtained with phase-coherent timing for PSRs J1846-0258 (n=2.65+/-0.01), B1509-58 (n=2.839+/-0.001) and B0540-69 (n=2.140+/-0.009). We discuss the implications of these results and possible physical explanations for them.
Regenerative braking on bicycles to power LED safety flashers
Collier, Ian M
2005-01-01T23:59:59.000Z
This work develops a method for capturing some of the kinetic energy ordinarily lost during braking on bicycles to power LED safety flashers. The system is designed to eliminate: (a) battery changing in popular LED flashers, ...
automotive drum brakes: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
well-known phenomena of acoustics of friction as the squealing disc brake and the singing wine glass. Oleg N. Kirillov 2007-08-07 130 The Ultra-High Energy Cosmic Ray Spectrum...
Adaptive Rollover Prevention for Automotive Vehicles with Differential Braking
Duffy, Ken
Adaptive Rollover Prevention for Automotive Vehicles with Differential Braking Selim Solmaz, switching, and tuning (MMST) paradigm [13, 14, 15] for preventing untripped rollover in automotive vehicles performance than its fixed robust counterpart. Keywords: Automotive control; Multiple models; Parameter
Investigation of aerodynamic braking devices for wind turbine applications
Griffin, D.A. [R. Lynette & Associates, Seattle, WA (United States)
1997-04-01T23:59:59.000Z
This report documents the selection and preliminary design of a new aerodynamic braking system for use on the stall-regulated AWT-26/27 wind turbines. The goal was to identify and design a configuration that offered improvements over the existing tip brake used by Advanced Wind Turbines, Inc. (AWT). Although the design objectives and approach of this report are specific to aerodynamic braking of AWT-26/27 turbines, many of the issues addressed in this work are applicable to a wider class of turbines. The performance trends and design choices presented in this report should be of general use to wind turbine designers who are considering alternative aerodynamic braking methods. A literature search was combined with preliminary work on device sizing, loads and mechanical design. Candidate configurations were assessed on their potential for benefits in the areas of cost, weight, aerodynamic noise, reliability and performance under icing conditions. As a result, two configurations were identified for further study: the {open_quotes}spoiler-flap{close_quotes} and the {open_quotes}flip-tip.{close_quotes} Wind tunnel experiments were conducted at Wichita State University to evaluate the performance of the candidate aerodynamic brakes on an airfoil section representative of the AWT-26/27 blades. The wind tunnel data were used to predict the braking effectiveness and deployment characteristics of the candidate devices for a wide range of design parameters. The evaluation was iterative, with mechanical design and structural analysis being conducted in parallel with the braking performance studies. The preliminary estimate of the spoiler-flap system cost was $150 less than the production AWT-26/27 tip vanes. This represents a reduction of approximately 5 % in the cost of the aerodynamic braking system. In view of the preliminary nature of the design, it would be prudent to plan for contingencies in both cost and weight.
Asbestos-free brake-lining materials for hydrogenerators
Lalonde, S.; Lanteigne, J. [Hydro-Quebec, Varennes, Quebec (Canada)
1995-11-01T23:59:59.000Z
Three different asbestos-free materials currently considered as new lining materials for hydrogenerator brakes were tested and compared to the original asbestos lining. Results show that these substitutes not only vary greatly from the original material in terms of mechanical properties and physical characteristics but also exhibit significantly different performances in braking tests. Consequently, these new materials are not entirely suitable for the intended application.
Magnetic braking of T Tauri stars
P. J. Armitage; C. J. Clarke
1995-12-05T23:59:59.000Z
We construct models for the rotation rates of T Tauri stars whose spin is regulated by magnetic linkage between the star and a surrounding accretion disc. Our models utilise a time-dependent disc code to follow the accretion process and include the effects of pre-main-sequence stellar evolution. We find that the initial disc mass controls the evolution of the star-disc system. For sufficiently massive discs, a stellar field of $\\sim$ 1 kG is able to regulate the spin rate to the observed values during the classical T Tauri phase. The field then acts to expel the disc and the star spins up at constant angular momentum as a weak-line system. Lower mass discs are ejected at an early epoch and fail to brake the star significantly. We extend the model to close binary systems, and find that the removal of angular momentum from the disc by the secondary significantly prolongs the inner disc lifetime. Such systems should therefore be relatively slow rotators. We also discuss the implications of our model for the spectral energy distributions and variability of T Tauri stars.
Oleg N. Kirillov
2007-08-22T23:59:59.000Z
We consider a gyroscopic system under the action of small dissipative and non-conservative positional forces, which has its origin in the models of rotating bodies of revolution being in frictional contact. The spectrum of the unperturbed gyroscopic system forms a "spectral mesh" in the plane "frequency -gyroscopic parameter" with double semi-simple purely imaginary eigenvalues at zero value of the gyroscopic parameter. It is shown that dissipative forces lead to the splitting of the semi-simple eigenvalue with the creation of the so-called "bubble of instability" - a ring in the three-dimensional space of the gyroscopic parameter and real and imaginary parts of eigenvalues, which corresponds to complex eigenvalues. In case of full dissipation with a positive-definite damping matrix the eigenvalues of the ring have negative real parts making the bubble a latent source of instability because it can "emerge" to the region of eigenvalues with positive real parts due to action of both indefinite damping and non-conservative positional forces. In the paper, the instability mechanism is analytically described with the use of the perturbation theory of multiple eigenvalues. As an example stability of a rotating circular string constrained by a stationary load system is studied in detail. The theory developed seems to give a first clear explanation of the mechanism of self-excited vibrations in the rotating structures in frictional contact, that is responsible for such well-known phenomena of acoustics of friction as the squealing disc brake and the singing wine glass.
Fuzzy logic electric vehicle regenerative antiskid braking and traction control system
Cikanek, S.R.
1994-10-25T23:59:59.000Z
An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control. 123 figs.
Paris-Sud XI, UniversitÃ© de
, residual friction, noise, vibrations, a new brake has been designed according to a modular principle which describes a new intelligent braking system for motor vehicles. A mechatronic approach helped to avoid some
Evaluation of driver braking performance to an unexpected object in the roadway
Picha, Dale Louis
1994-01-01T23:59:59.000Z
components, specifically whether the equation accurately reflects driver and vehicle behaviors during a braking maneuver. This research evaluated the two components of the SSD equation. Four field studies were conducted that evaluated driver braking...
Fuzzy logic electric vehicle regenerative antiskid braking and traction control system
Cikanek, Susan R. (Wixom, MI)
1994-01-01T23:59:59.000Z
An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control.
Evaluation of driver braking performance to an unexpected object in the roadway
Picha, Dale Louis
1994-01-01T23:59:59.000Z
components, specifically whether the equation accurately reflects driver and vehicle behaviors during a braking maneuver. This research evaluated the two components of the SSD equation. Four field studies were conducted that evaluated driver braking...
Regenerative braking device with rotationally mounted energy storage means
Hoppie, Lyle O. (Birmingham, MI)
1982-03-16T23:59:59.000Z
A regenerative braking device for an automotive vehicle includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (30) and an output shaft (32), clutches (50, 56) and brakes (52, 58) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. In a second embodiment the clutches and brakes are dispensed with and the variable ratio transmission is connected directly across the input and output shafts. In both embodiments the rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft rotates faster or relative to the output shaft and are torsionally relaxed to deliver energy to the vehicle when the output shaft rotates faster or relative to the input shaft.
Evaluation of Corrosion Failure in Tractor-Trailer Brake System
Wilson, DF
2002-10-22T23:59:59.000Z
As reported to ORNL, concomitant with the introduction of different deicing and anti-icing compounds, there was an increase in the brake failure rate of tractor-trailer trucks. A forensic evaluation of a failed brake system was performed. Optical and scanning electron microscopic evaluation showed corrosion to be mostly confined to the brake table/lining interface. The corrosion is non-uniform as is to be expected for plain carbon steel in chloride environments. This initial analysis found no evidence for the chlorides of calcium and magnesium, which are the newly introduced deicing and antiicing compounds and are less soluble in water than the identified chlorides of sodium and potassium, in the scale. The result could be as a result of non-exposure of the examined brake table to calcium and magnesium chloride. The mechanisms for the increased failure rate are postulated as being an increased rate of corrosion due to positive shifts in the corrosion potential, and an increased amount of corrosion due to an increased ''time of wetness'' that results from the presence of hygroscopic salts. Laboratory scale evaluation of the corrosion of plain carbon steel in simulated deicing and anti-icing solutions need to be performed to determine corrosion rates and morphological development of corrosion product, to compare laboratory data to in-service data, and to rank economically feasible replacement materials for low carbon steel. In addition, the mechanical behavior of the lining attached to the brake shoe table needs to be assessed. It is opined that an appropriate adjustment of materials could easily allow for a doubling of a brake table/lining lifetime. Suggestions for additional work, to clarify the mechanisms of rust jacking and to develop possible solutions, are described.
Calibration, Information, and Control Strategies for Braking to Avoid a Collision
effect. A new model is introduced according to which braking is controlled by keeping the perceived idealCalibration, Information, and Control Strategies for Braking to Avoid a Collision Brett R. Fajen Rensselaer Polytechnic Institute This study explored visual control strategies for braking to avoid collision
Airbus A320 Braking as Predicate-Action Peter B. Ladkin
Ladkin, Peter B.
Airbus A320 Braking as Predicate-Action Diagrams Peter B. Ladkin Universit¨at Bielefeld, Technische of the Airbus A320 braking systems contained in the Flight Crew Operating Manual. This helps identify to interest us and others in the design of the A320 braking system [FI.93a, FI.93b, FI.93c]. This paper
Oxygen-Diffused Titanium as a Candidate Brake Rotor Material
Qu, Jun [ORNL; Blau, Peter Julian [ORNL; Jolly, Brian C [ORNL
2009-01-01T23:59:59.000Z
Titanium alloys are one of several candidate materials for the next generation of truck disk brake rotors. Despite their advantages of lightweight relative to cast iron and good strength and corrosion resistance, titanium alloys are unlikely to be satisfactory brake rotor materials unless their friction and wear behavior can be significantly improved. In this study, a surface engineering process oxygen diffusion was applied to titanium rotors and has shown very encouraging results. The oxygen diffused Ti-6Al-4V (OD-Ti) was tested on a sub-scale brake tester against a flat block of commercial brake lining material and benchmarked against several other Ti-based materials, including untreated Ti-6Al-4V, ceramic particle-reinforced Ti composites (MMCs), and a thermal-spray-coated Ti alloy. With respect to friction, the OD-Ti outperformed all other candidate materials under the imposed test conditions with the friction coefficient remaining within a desirable range of 0.35-0.50, even under the harshest conditions when the disk surface temperature reached nearly 600 ?C. In addition, the OD-Ti showed significantly improved wear-resistance over the non-treated one and was even better than the Ti-based composite materials.
automotive brake materials: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
brake materials First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Multidisciplinary design optimization...
aircraft brake materials: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
brake materials First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 26 REDUCTION OF CADMTUM PLATING ON...
Brake Wear and Performance Test Final December 2009
Brake Wear and Performance Test Final Report December 2009 #12;FOREWORD This study focuses on using with assisting the State of Tennessee in identifying suitable PBBT machines, procuring a PBBT machine, installing the PBBT machine to be used in this research, and training Tennessee Department of Safety (TDOS) Staff
Many applications require brakes, for instance to decelerate or to
an error occurs in the process of a robotic arm. The energy consumption and actuation force of these brakes is very high. A team of TU Delft scientists developed a method to reduce the energy consumption. The energy consumption is high because an actuator has to generate a normal force between two friction
Braking index of isolated pulsars: open questions and ways forward
Hamil, Oliver
2015-01-01T23:59:59.000Z
Isolated pulsars are rotating neutron stars with accurately measured angular velocities $\\Omega$, and their time derivatives which show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a question of debate, the commonly accepted view is that it arises either through emission of magnetic dipole radiation (MDR) from a rotating magnetized body, through emission of a relativistic particle wind, or via higher order magnetic multipole or gravitational quadrupole radiation. The calculated energy loss by a rotating pulsar is model dependent and leads to the power law $\\dot{\\Omega}$ = -K $\\Omega^{\\rm n}$ where $n$ is called the braking index. The theoretical value for braking index is $n = 1, 3, 5$ for wind, MDR, quadrupole radiation respectively. The accepted view is that pulsar braking is strongly dominated by MDR. Highly precise observations of isolated pulsars yield braking index values in the range $1 < n < 2.8$ which are consistently less than the value pred...
TOWARDS GLOBAL CHASSIS CONTROL BY INTEGRATING THE BRAKE AND
Paris-Sud XI, UniversitÃ© de
. SzabÂ´o*, J. Bokor*, C. Poussot-Vassal**, O. Sename**, L. Dugard** *Computer and Automation Research active suspensions and an active brake is proposed to improve the safety of vehicles. The design is based of the method is demonstrated through a complex simulation example containing vehicle maneuvers. Keywords: LPV
Heavy and Overweight Vehicle Brake Testing: Five-Axle Combination Tractor-Flatbed Final Report
Lascurain, Mary Beth [ORNL; Capps, Gary J [ORNL; Franzese, Oscar [ORNL
2013-10-01T23:59:59.000Z
The Federal Motor Carrier Safety Administration, in coordination with the Federal Highway Administration, sponsored the Heavy and Overweight Vehicle Brake Testing (HOVBT) program in order to provide information about the effect of gross vehicle weight (GVW) on braking performance. Because the Federal Motor Carrier Safety Regulations limit the number of braking system defects that may exist for a vehicle to be allowed to operate on the roadways, the examination of the effect of brake defects on brake performance for increased loads is also relevant. The HOVBT program seeks to provide relevant information to policy makers responsible for establishing load limits, beginning with providing test data for a combination tractor/trailer. This testing was conducted on a five-axle combination vehicle with tractor brakes meeting the Reduced Stopping Distance requirement rulemaking. This report provides a summary of the testing activities, the results of various analyses of the data, and recommendations for future research. Following a complete brake rebuild, instrumentation, and brake burnish, stopping tests were performed from 20 and 40 mph with various brake application pressures (15 psi, 25 psi, 35 psi, 45 psi, 55 psi, and full system pressure). These tests were conducted for various brake conditions at the following GVWs: 60,000, 80,000, 91,000, 97,000, 106,000, and 116,000 lb. The 80,000-lb GVWs included both balanced and unbalanced loads. The condition of the braking system was also varied. To introduce these defects, brakes (none, forward drive axle, or rear trailer axle) were made inoperative. In addition to the stopping tests, performance-based brake tests were conducted for the various loading and brake conditions. Analysis of the stopping test data showed the stopping distance to increase with load (as expected) and also showed that more braking force was generated by the drive axle brakes than the trailer axle brakes. The constant-pressure stopping test data revealed a linear relationship between brake application pressure and was used to develop an algorithm to normalize stopping data for weight and initial speed.
Development of Diagnostic Algorithms for Air Brakes in Trucks
Dhar, Sandeep
2011-10-21T23:59:59.000Z
and the rear brake chamber using the predicted primary circuit pressure : : : : : : : : : : : : : : : : : : : : 54 33 Simulated response of the hybrid system : : : : : : : : : : : : : : : : 64 34 Steady-state estimate of z1 of the pneumatic hybrid system... with massless piston : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 67 xii FIGURE Page 35 Steady-state estimates of z1 and z2 of the pneumatic hybrid system : 70 36 (a) Mechanical hybrid system, (b) non-hybrid counterpart : : : : : : 70 37...
Energy Efficiency in Heavy Vehicle Tires, Drivetrains, and Braking Systems
Peter J. Blau
2000-04-26T23:59:59.000Z
This document was prepared to support the primary goals of the Department of Energy, Office of Heavy Vehicle Technologies. These were recently stated as follows: ''Develop by 2004 the enabling technologies for a class 7-8 truck with a fuel efficiency of 10 mpg (at 65 mph) which will meet prevailing emission standards. For Class 3-6 trucks operating on an urban driving cycle, develop by 2004 commercially viable vehicles that achieve at least double the fuel economy of comparable current vehicles (1999), and as a research goal, reduce criteria pollutants to 30% below EPA standards. Develop by 2004 the diesel engine enabling technologies to support large-scale industry dieselization of Class 1 and 2 trucks, achieving a 35 % fuel efficiency improvement over comparable gasoline-fueled trucks, while meeting applicable emissions standards.'' The enabling technologies for improving the fuel efficiency of trucks, include not only engine technologies but also technologies involved with lowering the rolling resistance of tires, reducing vehicle aerodynamic drag, improving thermal management, and reducing parasitic frictional losses in drive train components. Opportunities also exist for making better use of the energy that might ordinarily be dissipated during vehicle braking. Braking systems must be included in this evaluation since safety in truck operations is vital, and braking requirements are greater for vehicles having lowered resistance to rolling. The Office of Heavy Vehicle Technologies has initiated a program to improve the aerodynamics of heavy vehicles through wind tunnel testing, computational modeling, and on-road evaluations. That activity is described in a separate multi-year plan; therefore, emphasis in this document will be on tires, drive trains, and braking systems. Recent, dramatic fluctuations in diesel fuel prices have emphasized the importance of effecting savings in truck fuel economy by implementing new component designs and materials.
A mathematical model for air brake systems in the presence of leaks
Ramaratham, Srivatsan
2008-10-10T23:59:59.000Z
of the pneumatic subsystem. . . . . . . . . . . . . . . . . . 20 16 Pressure transients at 722 kPa (90 psi) supply pressure with no leak. 22 17 Schematic of the setup for leak corroboration tests. . . . . . . . . . . 27 18 Comparison of measured and predicted mass... of detecting and locating leaks[6]. Most of the performance tests and visual based inspection tests of the air brake system indirectly correlate pressure in the brake chamber with the torque output, brake pad temperature, push rod strokes etc[7], [8]. More...
Real-Time Dynamic Brake Assessment Proof of Concept Final Report
Lascurain, Mary Beth [ORNL; Franzese, Oscar [ORNL; Capps, Gary J [ORNL
2011-11-01T23:59:59.000Z
This proof-of-concept research was performed to explore the feasibility of using real-world braking data from commercial motor vehicles to make a diagnosis of brake condition similar to that of the performance-based brake tester (PBBT). This was done by determining the relationship between pressure and brake force (P-BF), compensating for the gross vehicle weight (GVW). The nature of this P-BF relationship (e.g., low braking force for a given brake application pressure) may indicate brake system problems. In order to determine the relationship between brake force and brake application pressure, a few key parameters of duty cycle information were collected. Because braking events are often brief, spanning only a few seconds, a sample rate of 10 Hz was needed. The algorithm under development required brake application pressure and speed (from which deceleration was calculated). Accurate weight estimation was also needed to properly derive the braking force from the deceleration. In order to ensure that braking force was the predominant factor in deceleration for the segments of data used in analysis, the data was screened for grade as well. Also, the analysis needed to be based on pressures above the crack pressure. The crack pressure is the pressure below which the individual brakes are not applied due the nature of the mechanical system. This value, which may vary somewhat from one wheel end to another, is approximately 10 psi. Therefore, only pressures 15 psi and above were used in the analysis. The Department of Energy s Medium Truck Duty Cycle research has indicated that under the real-world circumstances of the test vehicle brake pressures of up to approximately 30 psi can be expected. Several different types of data were collected during the testing task of this project. Constant-pressure stopping tests were conducted at several combinations of brake application pressure (15, 20, 25, and 30 psi), load conditions (moderately and fully laden), and speeds (20 and 30 mph). Data was collected at 10 Hz. Standard and stepped-pressure performance-based brake tests with brake pressure transducers were performed for each loading condition. The stepped-pressure test included the constant-pressure intervals of brake application at 15, 20, 25, and 30 psi. The PBBT data files included 10 Hz streaming data collected during the testing of each axle. Two weeks of real-world duty cycle (driving and braking) data was also collected at 10 Hz. Initial analysis of the data revealed that the data collected in the field (i.e., day-to-day operations) provided the same information as that obtained from the controlled tests. Analysis of the data collected revealed a strong linear relationship between brake application pressure and deceleration for given GVWs. As anticipated, initial speed was not found to be a significant factor in the deceleration-pressure relationship, unlike GVW. The positive results obtained from this proof of concept test point to the need for further research to expand this concept. A second phase should include testing over a wider range of speeds and include medium brake application pressures in addition to the low pressures tested in this research. Testing on multiple vehicles would also be of value. This future phase should involve testing to determine how degradation of braking performance affects the pressure-deceleration relationship.
Integrated vehicle dynamics control via coordination of active front steering and rear braking
Paris-Sud XI, UniversitÃ© de
Integrated vehicle dynamics control via coordination of active front steering and rear brakingComputer and Automation Research Institue, Hungarian Academy of Sciences, Kende u. 13-17, H-1111, Budapest, Hungary, Email front steering and rear braking in a driver- assist system for vehicle yaw control. The proposed control
Vehicle yaw control via coordinated use of steering/braking systems
Paris-Sud XI, UniversitÃ© de
Vehicle yaw control via coordinated use of steering/braking systems M. Doumiati, O. Sename, J.sename@gipsa-lab.grenoble-inp.fr) Computer and Automation Research Institute, Hungarian Academy of Sciences, Kende u. 13-17, H-1111, Budapest with steer- ing/braking coordination task for vehicle yaw control. For steerability enhancement, only active
Modeling the pneumatic subsystem of a S-cam air brake system
Coimbatore Subramanian, Shankar
2004-09-30T23:59:59.000Z
The air brake system is one of the critical components in ensuring the safe operation of any commercial vehicle. This work is directed towards the development of a fault-free model of the pneumatic subsystem of the air brake system. This model can...
Modeling the pneumatic relay valve of an s-cam air brake
Vilayannur Natarajan, Shankar
2005-08-29T23:59:59.000Z
by the driver, when there are no faults or defects in the brake system. This thesis is aimed at modeling and experimentally corroborating a subsystem of an air brake system, namely the pneumatic relay valve. The pneumatic relay valve takes a input signal from...
Fault tolerant control of automatically controlled vehicles in response to brake system failures
Hsien, Li-Wei
1998-01-01T23:59:59.000Z
in the brake system is vital. In this thesis, nonlinear failure detection filters are used for fault detection of sensors and actuators in a class of nonlinear systems. In this thesis, the effects of brake system failures in an AHS where the vehicle steering...
Fault tolerant control of automatically controlled vehicles in response to brake system failures
Hsien, Li-Wei
1998-01-01T23:59:59.000Z
in the brake system is vital. In this thesis, nonlinear failure detection filters are used for fault detection of sensors and actuators in a class of nonlinear systems. In this thesis, the effects of brake system failures in an AHS where the vehicle steering...
Emission Factor for Antimony in Brake Abrasion Dusts as One of the
Short, Daniel
originating from automobiles. Abrasion dusts from commercially available brake pads (nonasbestos organic type factors originating from automobiles were approximately 32 Âµg Sb/braking/car for PM10 and 22 Âµg Sb of automobiles to the atmospheric Sb concen- tration. The emission factors of pollutants from automobiles have
Wind turbine trailing-edge aerodynamic brake design
Quandt, G.
1996-01-01T23:59:59.000Z
This report describes the design of a centrifugally actuated aerodynamic-overspeed device for a horizontal-axis wind turbine. The device will meet the following criteria; (1) It will be effective for airfoil angles of attack 0{degrees} to 45{degrees}. (2) It will be stowed inside the blade profile prior to deployment. (3) It will be capable of offsetting the positive torque produced by the overall blade. (4) Hinge moments will be minimized to lower actuator loads and cost. (5) It will be evaluated as a potential power modulating active rotor-control system. A literature review of aerodynamic braking devices was conducted. Information from the literature review was used to conceptualize the most effective devices for subsequent testing and design. Wind-tunnel test data for several braking devices are presented in this report. Using the data for the most promising configuration, a preliminary design was developed for a MICON 65/13 wind turbine with Phoenix 7.9-m rotor blades.
Cooper, T.C.; McGlothlin, J.D.; Godbey, F.W.; Sheehy, J.W.; O'Brien, D.M.
1986-05-01T23:59:59.000Z
A walk-through survey of control technology for reducing asbestos exposure during maintenance and repair of vehicular brakes was conducted at Northwest Local School District, Cincinnati, Ohio in January, 1986. The primary method for controlling and collecting dust during brake servicing was a wet-washing technique and good work practices, ensuring that exposure to hazardous physical or chemical agents was reduced or eliminated. Also available was an enclosed-type brake assembly cleaner designed to be connected to the shop air and a vacuum system. The brake assembly cleaner did not have a viewing port to examine the area being cleaned. The operator had to remove the unit to inspect the cleaned area potentially exposing himself to any dust remaining on the brake shoes or hub. The unit itself was a potential dust source as it was designed to fit 16-inch wheels and did not form a tight seal on the smaller 15-inch wheels of the newer buses. The authors conclude that the wet wash technique is an excellent method for controlling asbestos emissions during brake maintenance. The vacuum brake-assembly cleaner is inadequate and potentially hazardous. An in-depth survey of the wet technique is recommended.
Braking index of isolated uniformly rotating magnetized pulsars
Hamil, Oliver; Urbanec, Martin; Urbancova, Gabriela
2015-01-01T23:59:59.000Z
Isolated pulsars are rotating neutron stars with accurately measured angular velocities $\\Omega$, and their time derivatives which show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a question of debate in detail, the commonly accepted view is that it arises through emission of magnetic dipole radiation (MDR) from a rotating magnetized body. Other processes, including the emission of gravitational radiation, and of relativistic particles (pulsar wind), are also being considered. The calculated energy loss by a rotating pulsar with a constant moment of inertia is assumed proportional to a model dependent power of $\\Omega$. This relation leads to the power law $\\dot{\\Omega}$ = -K $\\Omega^{\\rm n}$ where $n$ is called the braking index. The MDR model predicts $n$ exactly equal to 3. Selected observations of isolated pulsars provide rather precise values of $n$, individually accurate to a few percent or better, in the range 1$ <$ n $ < $ 2.8, which is consi...
Van Wagenen, H.D.
1987-03-01T23:59:59.000Z
Exposure to asbestos during the servicing of brakes on state-owned vehicles at the Bureau of Vehicle Management Maintenance Division, Harrisburg, Pennsylvania, was investigated as part of a study of control technologies. Brakes had been serviced at this garage facility for the previous year using a BCE-1000 Clayton brake-cleaning unit, sized for cars, vans, and pickups. The brake-cleaning unit consisted of a transparent enclosure hood and a HEPA vacuum filter dust collector, designed to contain and collect all brake-lining dust during vehicular brake maintenance and replacement. The authors conclude that the Clayton BCE-1000 dust-control unit appeared to be effective in containing and collecting brake dust during all vehicular brake maintenance and replacement jobs in this situation.
Vaziri, Ashkan
energy storage system and subsequently used for the propulsion, significantly reducing the vehicle the brake of a vehicle [1]. The total energy dissipated through braking during a typical urban area drive
On The Use of Eddy Current Brakes as Tunable, Fast Turn-On Viscous Dampers For Haptic Rendering
Hayward, Vincent
On The Use of Eddy Current Brakes as Tunable, Fast Turn-On Viscous Dampers For Haptic Rendering, linear dampers for haptic rendering using a prototype haptic device outfitted with eddy current brakes discuss the results from haptic experiments for rendering viscosity, virtual walls and virtual friction
Hayward, Vincent
Initial results using Eddy Current Brakes as Fast Turn-on, Programmable Physical Dampers for Haptic Machines McGill University, Montr´eal, Qu´ebec, Canada ABSTRACT We demonstrate the use of eddy current propose an alternate method to create damping in a haptic interface that uses eddy current brakes. 2 EDDY
Miller, P.A.; Sukley, R.
1996-09-01T23:59:59.000Z
The purpose of this project was to evaluate the performance of asphalt containing various percentages of brake lining as an aggregate, and compare its performance to that of normal asphalt containing natural aggregate. This project is an effort to explore alternate ways to use waste product. Four test section of FB-2 Modified mix containing brake lining materials were placed in July 1992 along with one control section on SR 3022 in Mercer county. To date all sections are performing satisfactory, and Brake linings should be recommended as a viable partial replacement of aggregate in bituminous materials. This study only considered the performance of only off-spec brake linings, therefore, any performance data or enviromental effects of placement of used brake material should be addressed.
REPORT on the TRUCK BRAKE LINING WORKSHOP and FLEET OPERATORS' SURVEY
Blau, P.J.
2003-02-03T23:59:59.000Z
The report summarizes what transpired during brake linings-related workshop held at the Fall 2003 meeting of the Technology and Maintenance Council (TMC) in Charlotte, NC. The title of the workshop was ''Developing a Useful Friction Material Rating System''. It was organized by a team consisting of Peter Blau (Oak Ridge National Laboratory), Jim Britell (National Highway Traffic Safety Administration), and Jim Lawrence (Motor and Equipment Manufacturers Association). The workshop was held under the auspices of TMC Task Force S6 (Chassis), chaired by Joseph Stianche (Sanderson Farms, Inc.). Six invited speakers during the morning session provided varied perspectives on testing and rating aftermarket automotive and truck brake linings. They were: James R. Clark, Chief Engineer, Foundation Brakes and Wheel Equipment, Dana Corporation, Spicer Heavy Axle and Brake Division; Charles W. Greening, Jr, President, Greening Test Labs; Tim Duncan, General Manager, Link Testing Services;Dennis J. McNichol, President, Dennis NationaLease; Jim Fajerski, Business Manager, OE Sales and Applications Engineering, Federal Mogul Corporation; and Peter J. Blau, Senior Materials Development Engineer, Oak Ridge National Laboratory. The afternoon break-out sessions addressed nine questions concerning such issues as: ''Should the federal government regulate aftermarket lining quality?''; ''How many operators use RP 628, and if so, what's good or bad about it?''; and ''Would there be any value to you of a vocation-specific rating system?'' The opinions of each discussion group, consisting of 7-9 participants, were reported and consolidated in summary findings on each question. Some questions produced a greater degree of agreement than others. In general, the industry seems eager for more information that would allow those who are responsible for maintaining truck brakes to make better, more informed choices on aftermarket linings. A written fleet operator survey was also conducted during the TMC meeting. Twenty-one responses were received, spanning fleet sizes between 12 and 170,000 vehicles. Responses are summarized in a series of tables separated into responses from small (100 or fewer powered vehicles), medium (101-1000 vehicles), and large fleets (>1000 vehicles). The vast majority of fleets do their own brake maintenance, relying primarily on experience and lining manufactures to select aftermarket linings. At least half of the responders are familiar to some extent with TMC Recommended Practice 628 on brake linings, but most do not use this source of test data as the sole criterion to select linings. Significant shortfalls in the applicability of TMC RP 628 to certain types of brake systems were noted.
Neutron scattering residual stress measurements on gray cast iron brake discs
Spooner, S.; Payzant, E.A.; Hubbard, C.R. [and others
1996-11-01T23:59:59.000Z
Neutron diffraction was used to investigate the effects of a heat treatment designed to remove internal residual stresses in brake discs. It is believed that residual stresses may change the rate of deformation of the discs during severe braking conditions when the disc temperature is increased significantly. Neutron diffraction was used to map out residual strain distributions in a production disc before and after a stress-relieving heat treatment. Results from these neutron diffraction experiments show that some residual strains were reduced by as much as 400 microstrain by stress relieving. 5 refs., 5 figs., 1 tab.
Classical and quantum Big Brake cosmology for scalar field and tachyonic models
Kamenshchik, A. Yu. [Dipartimento di Fisica e Astronomia and INFN, Via Irnerio 46, 40126 Bologna (Italy) and L.D. Landau Institute for Theoretical Physics of the Russian Academy of Sciences, Kosygin str. 2, 119334 Moscow (Russian Federation); Manti, S. [Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa (Italy)
2013-02-21T23:59:59.000Z
We study a relation between the cosmological singularities in classical and quantum theory, comparing the classical and quantum dynamics in some models possessing the Big Brake singularity - the model based on a scalar field and two models based on a tachyon-pseudo-tachyon field . It is shown that the effect of quantum avoidance is absent for the soft singularities of the Big Brake type while it is present for the Big Bang and Big Crunch singularities. Thus, there is some kind of a classical - quantum correspondence, because soft singularities are traversable in classical cosmology, while the strong Big Bang and Big Crunch singularities are not traversable.
Anirban Kundu
2008-06-24T23:59:59.000Z
This is a brief discussion of the following features of the Universal Extra Dimension (UED) model: (i) Formulation, (ii) Indirect bounds, (iii) Collider search and the Inverse Problem, (iv) Astrophysical bounds, and (v) UED with two extra dimensions.
Achieving Consistent Maximum Brake Torque with Varied Injection Timing in a DI Diesel Engine
Kroeger, Timothy H
2013-09-19T23:59:59.000Z
The brake torque of a direct-injection diesel engine is known to plateau over a range of injection timings. Injection timing affects the engine’s ignition delay and the fractions of fuel which burn in premixed and diffusion modes. Therefore...
Regenerative Braking for an Electric Vehicle Using Ultracapacitors and a Buck-Boost Converter
Catholic University of Chile (Universidad Católica de Chile)
Regenerative Braking for an Electric Vehicle Using Ultracapacitors and a Buck-Boost Converter Juan for an Electric Vehicle has been simulated. The purpose of this device is to allow higher accelerations, similar in shape and size to a Chevrolet S-10. This vehicle was already converted to an electric car
A study of factors affecting foot movement time in a braking maneuver
Berman, Andrea Helene
1994-01-01T23:59:59.000Z
The nature of foot movement time (MT) in an actual braking maneuver and in a stationary vehicle was investigated regarding the effects of age and gender of the driver and nature of the stimulus to which the driver was responding. ANOVAs showed...
Modeling the pneumatic relay valve of an s-cam air brake
Vilayannur Natarajan, Shankar
2005-08-29T23:59:59.000Z
inspections. For example, defects like chafed hoses do not show pronounced effect in performance based tests. In the past only a few cases of air leak violations have been detected by the conventional performance based testers namely roller dynamometer... detected by the performance based system since they had a pronounced effect on the brake force. Reference [6] emphasizes on the need for a standardized, hand held diagnostic tool for improving the existing inspections. A model based, performance based diag...
Variations in gear fatigue life for different wind turbine braking strategies
McNiff, B.P. (Second Wind, Inc., Somerville, MA (USA)); Musial, W.D. (Solar Energy Research Inst., Golden, CO (USA)); Errichello, R. (GEARTECH, Albany, CA (USA))
1991-06-01T23:59:59.000Z
A large number of gearbox failures have occurred in the wind industry in a relatively short period, many because service loads were underestimated. High-torque transients that occur during starting and stopping are difficult to predict and may be overlooked in specifying gearbox design. Although these events comprise a small portion of total load cycles, they can be the most damaging. The severity of these loads varies dramatically with the specific configuration of the wind turbine. The large number of failures in Danish-designed Micon 65 wind turbines prompted this investigation. The high-speed and low-speed shaft torques were measured on a two-stage helical gearbox of a single Micon 65 turbine. Transient events and normal running loads were combined statistically to obtain a typical annual load spectrum. The pitting and bending fatigue lives of the gear teeth were calculated by using Miner's rule for four different high-speed shaft brake configurations. Each breaking scenario was run for both a high- and a low-turbulence normal operating load spectrum. The analysis showed increases in gear life by up to a factor of 25 when the standard high-speed shaft brake is replaced with a dynamic brake or modified with a damper. 9 refs., 9 figs., 3 tabs.
Gravity, Dimension, Equilibrium, & Thermodynamics
Jerome Perez
2006-03-30T23:59:59.000Z
Is it actually possible to interpret gravitation as space's property in a pure classical way. Then, we note that extended self-gravitating system equilibrium depends directly on the number of dimension of the space in which it evolves. Given those precisions, we review the principal thermodynamical knowledge in the context of classical gravity with arbitrary dimension of space. Stability analyses for bounded 3D systems, namely the Antonov instability paradigm, are then rapproched to some amazing properties of globular clusters and galaxies.
Collapse of Magnetized Singular Isothermal Toroids: II. Rotation and Magnetic Braking
A. Allen; Z. Y. Li; F. H. Shu
2003-11-17T23:59:59.000Z
We study numerically the collapse of rotating, magnetized molecular cloud cores, focusing on rotation and magnetic braking during the main accretion phase of isolated star formation. Motivated by previous numerical work and analytic considerations, we idealize the pre-collapse core as a magnetized singular isothermal toroid, with a constant rotational speed everywhere. The collapse starts from the center, and propagates outwards in an inside-out fashion, satisfying exact self-similarity in space and time. For rotation rates and field strengths typical of dense low-mass cores, the main feature remains the flattening of the mass distribution along field lines -- the formation of a pseudodisk, as in the nonrotating cases. The density distribution of the pseudodisk is little affected by rotation. On the other hand, the rotation rate is strongly modified by pseudodisk formation. Most of the centrally accreted material reaches the vicinity of the protostar through the pseudodisk. The specific angular momentum can be greatly reduced on the way, by an order of magnitude or more, even when the pre-collapse field strength is substantially below the critical value for dominant cloud support. The efficient magnetic braking is due to the pinched geometry of the magnetic field in the pseudodisk, which strengthens the magnetic field and lengthens the level arm for braking. Both effects enhance the magnetic transport of angular momentum from inside to outside. The excess angular momentum is carried away in a low-speed outflow that has, despite claims made by other workers, little in common with observed bipolar molecular outflows. We discuss the implications of our calculations for the formation of true disks that are supported against gravity by rotation.
Probability of failure of the waste hoist brake system at the Waste Isolation Pilot Plant (WIPP)
Greenfield, M.A. [Univ. of California, Los Angeles, CA (United States); Sargent, T.J. [Univ. of Chicago, IL (United States)]|[Stanford Univ., CA (United States). Hoover Institution
1998-01-01T23:59:59.000Z
In its most recent report on the annual probability of failure of the waste hoist brake system at the Waste Isolation Pilot Plant (WIPP), the annual failure rate is calculated to be 1.3E({minus}7)(1/yr), rounded off from 1.32E({minus}7). A calculation by the Environmental Evaluation Group (EEG) produces a result that is about 4% higher, namely 1.37E({minus}7)(1/yr). The difference is due to a minor error in the US Department of Energy (DOE) calculations in the Westinghouse 1996 report. WIPP`s hoist safety relies on a braking system consisting of a number of components including two crucial valves. The failure rate of the system needs to be recalculated periodically to accommodate new information on component failure, changes in maintenance and inspection schedules, occasional incidents such as a hoist traveling out-of-control, either up or down, and changes in the design of the brake system. This report examines DOE`s last two reports on the redesigned waste hoist system. In its calculations, the DOE has accepted one EEG recommendation and is using more current information about the component failures rates, the Nonelectronic Parts Reliability Data (NPRD). However, the DOE calculations fail to include the data uncertainties which are described in detail in the NPRD reports. The US Nuclear Regulatory Commission recommended that a system evaluation include mean estimates of component failure rates and take into account the potential uncertainties that exist so that an estimate can be made on the confidence level to be ascribed to the quantitative results. EEG has made this suggestion previously and the DOE has indicated why it does not accept the NRC recommendation. Hence, this EEG report illustrates the importance of including data uncertainty using a simple statistical example.
Hybrid Braking System for Non-Drive Axles | Department of Energy
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
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 DataDepartment of Energy Your Density Isn't YourTransport(Fact Sheet), GeothermalGridHYDROGEND D e e pShade YourHybirdBraking System for
Rau, Scott James
2013-01-29T23:59:59.000Z
Concepts and technologies described herein provide for an accurate and cost-effective method for rotating a solar array disk for tracking the movement of the sun. According to various aspects, a motor includes a fixed caliper and a translating caliper positioned adjacent to one another. Electromagnetically controlled brakes on the translating caliper grip the solar array disk while adjacent, but spaced apart, electromagnets on the fixed caliper and the translating caliper are energized to create an attractive force that pulls the translating caliper with the solar array disk toward the fixed caliper. After reaching the fixed caliper, brakes on the fixed caliper are engaged with the disk, brakes on the translating caliper are released from the disk, and the translating caliper is pushed back to the starting location where the process repeats until the desired rotation is completed.
Big Mysteries: Extra Dimensions
Lincoln, Don
2014-08-07T23:59:59.000Z
The weakness of gravity compared to the other subatomic forces is a real mystery. While nobody knows the answer, one credible solution is that gravity has access to more spatial dimensions than the other three known forces. In this video, Fermilab's Dr. Don Lincoln describes this idea, with the help of some very urbane characters.
Web Style Guide Fixed Dimension
Web Style Guide KEY: Fixed Dimension: Variable Dimension: V1.1, SEPTEMBER 2010 #12;Page 2 Table PAGE NEWS & EVENTS PAGE Fonts & Colors FONTS COLORS Web Writing Guidelines WEB WRITING GUIDELINES Web
Brown, Thomas B., M. Eng. Massachusetts Institute of Technology
2010-01-01T23:59:59.000Z
In this paper, we propose CityCarControl, a system to manage the steering, braking, and throttle of a new class of intra-city electric vehicles. These vehicles have a focus on extreme light-weight and a small parking ...
Hopkins, Jennifer Susan
1995-01-01T23:59:59.000Z
driving game. Superimposed on the game screen was the image of a car which appeared to the driver to be ahead of him/her. The image enlarged in size, appearing to be a car applying its brakes. The participant was instructed to react as he would in a real...
Uncertainty-Enabled Design of a Rocket Sled Track Switch Drs. Jordan E. Massad and Matthew R. Brake
Uncertainty-Enabled Design of a Rocket Sled Track Switch Drs. Jordan E. Massad and Matthew R. Brake Sandia National Laboratories, New Mexico Rocket sled tracks provide a dynamically rich environment acceleration profile, the switch closes to complete a circuit for instrument activation. Preliminary tests
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 Delicious Rank EERE: Alternative Fuels Data Center Home PageStationGreenhouse GasCalifornia State0
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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 Delicious Rank EERE: Alternative Fuels Data Center HomeIdle Reduction WeightRebate -
Motivation and definitions Dimension theory
Climenhaga, Vaughn
Motivation and definitions Dimension theory Results: old and new Multifractal analysis of Birkhoff averages #12;Motivation and definitions Dimension theory Results: old and new Outline 1 Motivation and definitions A multifractal decomposition Example 2 Dimension theory Quantifying level sets A dynamically
Collapse of Magnetized Singular Isothermal Toroids: II. Rotation and Magnetic Braking
Allen, A; Shu, F H
2003-01-01T23:59:59.000Z
We study numerically the collapse of rotating, magnetized molecular cloud cores, focusing on rotation and magnetic braking during the main accretion phase of isolated star formation. Motivated by previous numerical work and analytic considerations, we idealize the pre-collapse core as a magnetized singular isothermal toroid, with a constant rotational speed everywhere. The collapse starts from the center, and propagates outwards in an inside-out fashion, satisfying exact self-similarity in space and time. For rotation rates and field strengths typical of dense low-mass cores, the main feature remains the flattening of the mass distribution along field lines -- the formation of a pseudodisk, as in the nonrotating cases. The density distribution of the pseudodisk is little affected by rotation. On the other hand, the rotation rate is strongly modified by pseudodisk formation. Most of the centrally accreted material reaches the vicinity of the protostar through the pseudodisk. The specific angular momentum can b...
Pochiraju, Anirudh
2012-08-31T23:59:59.000Z
This thesis presents a flywheel based mechanical regenerative braking system (RBS) concept for a Formula SAE type race car application, to improve the performance and/or efficiency of the racecar. A mechanical system is chosen to eliminate losses...
Running couplings in extra dimensions
Jisuke Kubo; Haruhiko Terao; George Zoupanos
2000-10-07T23:59:59.000Z
The regularization scheme dependence of running couplings in extra compactified dimensions is discussed. We examine several regularization schemes explicitly in order to analyze the scheme dependence of the Kaluza-Klein threshold effects, which cause the power law running, in the case of the scalar theory in five dimensions with one dimension compactified. It is found that in 1-loop order, the net difference in the running of the coupling among the different schemes is reduced to be rather small after finite renormalization. An additional comment concerns the running couplings in the warped extra dimensions which are found to be regularization dependent above TeV scale.
Reduced-dimension transistors: Reduced-dimension transistors
Pulfrey, David L.
1 Reduced-dimension transistors: the HEMT LECTURE 20 Â· Reduced-dimension transistors Â· HEMT Â· 2-D;8 For a finite well Â· Wavefunction not completely confined Â· Use undoped spacer #12;9 Employment of a spacer scattering (Âµ ). Â· Electrons and donors separated no I I scattering, i.e., Âµ Â· Undoped spacer also helps
String universality in ten dimensions
Allan Adams; Oliver DeWolfe; Washington Taylor
2014-10-29T23:59:59.000Z
We show that the ${\\cal N}=1$ supergravity theories in ten dimensions with gauge groups $U(1)^{496}$ and $E_8 \\times U(1)^{248}$ are not consistent quantum theories. Cancellation of anomalies cannot be made compatible with supersymmetry and abelian gauge invariance. Thus, in ten dimensions all supersymmetric theories of gravity without known inconsistencies are realized in string theory.
A Braking Index for the Young, High-Magnetic-Field, Rotation-Powered Pulsar in Kes 75
Margaret A. Livingstone; Victoria M. Kaspi; E. V. Gotthelf; Lucien Kuiper
2006-04-21T23:59:59.000Z
We present the first phase-coherent measurement of a braking index for the young, energetic rotation-powered pulsar PSR J1846-0258. This 324 ms pulsar is located at the center of the supernova remnant Kes 75 and has a characteristic age of tau_c = 723 years, a spin-down energy of 8.3x10^{36}erg/s, and inferred magnetic field of 4.9x10^{13} G. Two independent phase-coherent timing solutions are derived which together span 5.5 yr of data obtained with the Rossi X-ray Timing Explorer. In addition, a partially phase-coherent timing analysis confirms the fully phase-coherent result. The measured value of the braking index, n=2.65+/-0.01, is significantly less than 3, the value expected from magnetic dipole radiation, implying another physical process must contribute to the pulsar's rotational evolution. Assuming the braking index has been constant since birth, we place an upper limit on the spin-down age of J1846-0258 of 884 yr, the smallest age estimate of any rotation-powered pulsar.
Duchowski, Andrew T.
the safety of a steel cage with airbags and anti-lock brakes for a wispy two-wheeled exoskeleton as they make
Horváth, Zsolt; Kamenshchik, Alexander Yu; Gergely, László Á
2015-01-01T23:59:59.000Z
The evolution of a closed Friedmann universe filled by a tachyon scalar field with a trigonometric potential and cold dark matter (CDM) is investigated. A subset of the evolutions consistent to 1$\\sigma $ confidence level with the Union 2.1 supernova data set is identified. The evolutions of the tachyon field are classified. Some of them evolve into a de Sitter attractor, while others proceed through a pseudo-tachyonic regime into a sudden future singularity. Critical evolutions leading to Big Brake singularities in the presence of CDM are found and a new type of cosmological evolution characterized by singularity avoidance in the pseudo-tachyon regime is presented.
Rahim, A.H.M.A.; Alamgir, D.A.H.
1988-08-01T23:59:59.000Z
A control strategy for dynamic braking resistor and shunt reactor is proposed for stabilization of power systems when subject to large disturbances. The time optimal control is derived as a function of synchronous machine power, its rotor angular position and speed deviation. The response for a single machine system with the proposed control has been compared with that from the time optimal solution obtained through the steepest descent method. The strategy has also been tested on two multimachine systems. Results indicate that the proposed strategy provides a simple and effective method of stabilization under transient emergency conditions.
Twist operators in higher dimensions
Ling-Yan Hung; Robert C. Myers; Michael Smolkin
2014-07-24T23:59:59.000Z
We study twist operators in higher dimensional CFT's. In particular, we express their conformal dimension in terms of the energy density for the CFT in a particular thermal ensemble. We construct an expansion of the conformal dimension in power series around n=1, with n being replica parameter. We show that the coefficients in this expansion are determined by higher point correlations of the energy-momentum tensor. In particular, the first and second terms, i.e. the first and second derivatives of the scaling dimension, have a simple universal form. We test these results using holography and free field theory computations, finding agreement in both cases. We also consider the `operator product expansion' of spherical twist operators and finally, we examine the behaviour of correlators of twist operators with other operators in the limit n ->1.
Low-Income Weatherization: The Human Dimension
Broader source: Energy.gov [DOE]
This presentation focuses on how the human dimension saves energy within low-income weatherization programs.
Deconstructing unparticles in higher dimensions
Lee, Jong-Phil [Korea Institute for Advanced Study, Seoul 130-722 (Korea, Republic of)
2009-04-01T23:59:59.000Z
Unparticles are realized by deconstruction in higher extra dimensions. It is shown that in this framework when the scale invariance is broken, the corresponding spectral function of the unparticle is shifted by an amount of the breaking scale. The result strongly supports the conventional ansatz for the spectral function of the unparticle in the literature.
crystal nickel a hree dimension
Braun, Paul
Zhenting 1 Department 2 Departmen ABSTRACT This pape crystal nickel a hree dimension photonic cryst polystyrene op silicon chips, volume fraction can be controlle nickel structure hen sacrificed volume fraction reports microm crystal structur or alumina she nickel microca microstructure further electrop volume
Octupolar order in two dimensions
Epifanio G. Virga
2015-03-16T23:59:59.000Z
Octupolar order is described in two space dimensions in terms of the maxima (and conjugated minima) of the probability density associated with a third-rank, fully symmetric and traceless tensor. Such a representation is shown to be equivalent to diagonalizing the relevant third-rank tensor, an equivalence which however is only valid in the two-dimensional case.
Resource dimensioning through buffer sampling
Boucherie, Richard J.
, theoretical dimensioning formulae that estimate the required capacity C as a function of the input traffic the buffer content, estimates the buffer content distribution, and `inverts' this to the variance. We of capacity that should be added, advanced modeling and performance techniques are required. These predictions
Carpick, Robert W.
Hydraulic Drivetrain and Regenerative Braking Team 13: Andrew Brown, Karan Desai, Andrew Mc Pressure Reservior Filter Variable Vane Pump Motor/Pump Hydraulic Accumulators Solenoid Valve Relief Valve Suction Line Since their development in 2006, hydraulic drivetrain systems have gained considerable
Grujicic, Mica
Finite element analysis of the effect of up-armouring on the off-road braking and sharp-mobility multi-purpose wheeled vehicle, off-road vehicle performance, finite element modelling and simulations revision for publication on 15 June 2009. DOI: 10.1243/09544070JAUTO1187 Abstract: A comprehensive finite
Critical Gravity in Four Dimensions
Lue, H. [China Economics and Management Academy, Central University of Finance and Economics, Beijing 100081 (China); Institute for Advanced Study, Shenzhen University, Nanhai Avenue 3688, Shenzhen 518060 (China); Pope, C. N. [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, College Station, Texas 77843 (United States); DAMTP, Centre for Mathematical Sciences, Cambridge University, Wilberforce Road, Cambridge CB3 OWA (United Kingdom)
2011-05-06T23:59:59.000Z
We study four-dimensional gravity theories that are rendered renormalizable by the inclusion of curvature-squared terms to the usual Einstein action with a cosmological constant. By choosing the parameters appropriately, the massive scalar mode can be eliminated and the massive spin-2 mode can become massless. This ''critical'' theory may be viewed as a four-dimensional analogue of chiral topologically massive gravity, or of critical 'new massive gravity' with a cosmological constant, in three dimensions. We find that the on-shell energy for the remaining massless gravitons vanishes. There are also logarithmic spin-2 modes, which have positive energy. The mass and entropy of standard Schwarzschild-type black holes vanish. The critical theory might provide a consistent toy model for quantum gravity in four dimensions.
Dark Energy From Fifth Dimension
H. Alavirad; N. Riazi
2008-01-21T23:59:59.000Z
Observational evidence for the existence of dark energy is strong. Here we suggest a model which is based on a modified gravitational theory in 5D and interpret the 5th dimension as a manifestation of dark energy in the 4D observable universe. We also obtain an equation of state parameter which varies with time. Finally, we match our model with observations by choosing the free parameters of the model.
Greenfield, M.A. [Univ. of California, Los Angeles, CA (United States); Sargent, T.J.
1995-11-01T23:59:59.000Z
The Environmental Evaluation Group (EEG) previously analyzed the probability of a catastrophic accident in the waste hoist of the Waste Isolation Pilot Plant (WIPP) and published the results in Greenfield (1990; EEG-44) and Greenfield and Sargent (1993; EEG-53). The most significant safety element in the waste hoist is the hydraulic brake system, whose possible failure was identified in these studies as the most important contributor in accident scenarios. Westinghouse Electric Corporation, Waste Isolation Division has calculated the probability of an accident involving the brake system based on studies utilizing extensive fault tree analyses. This analysis conducted for the U.S. Department of Energy (DOE) used point estimates to describe the probability of failure and includes failure rates for the various components comprising the brake system. An additional controlling factor in the DOE calculations is the mode of operation of the brake system. This factor enters for the following reason. The basic failure rate per annum of any individual element is called the Event Probability (EP), and is expressed as the probability of failure per annum. The EP in turn is the product of two factors. One is the {open_quotes}reported{close_quotes} failure rate, usually expressed as the probability of failure per hour and the other is the expected number of hours that the element is in use, called the {open_quotes}mission time{close_quotes}. In many instances the {open_quotes}mission time{close_quotes} will be the number of operating hours of the brake system per annum. However since the operation of the waste hoist system includes regular {open_quotes}reoperational check{close_quotes} tests, the {open_quotes}mission time{close_quotes} for standby components is reduced in accordance with the specifics of the operational time table.
Human Dimensions of Wildlife Research Norman Dandy
Human Dimensions of Wildlife Research Norman Dandy Social & Economic Research Group #12;Wildlife) · Human-dimensions of species management (HDSM) Research Projects #12;Collaborative Frameworks for Land of woodland landscapes discussion groups, · Choice experiments, · Fellowships / Placements, · Newsletters
DarniÃ¨re, Luck
(Co)dimension dans les alg`ebres (co)Heyting Luck Darni`ere, Markus Junker (Co)dimension ComplÂ´etion PrÂ´ecompacitÂ´e DensitÂ´e et scission Mod`ele complÂ´etion SÂ´eminaire DDG, Paris 7 (Co)dimension dans les alg`ebres (co)Heyting Luck Darni`ere Markus Junker 10 novembre 2009 #12;(Co)dimension dans les alg
DEPARTMENT OF HUMAN DIMENSIONS OF NATURAL RESOURCES
CODE DEPARTMENT OF HUMAN DIMENSIONS OF NATURAL RESOURCES College of Natural Resources Colorado;3 DEPARTMENT OF NATURAL HUMAN DIMENSIONS OF NATURAL RESOURCES CODE ARTICLE I. GOAL AND OBJECTIVES A. DEPARTMENT MISSION The mission of the Department of Human Dimensions of Natural Resources is to contribute
Statics and Dynamics of Spin and Electric Dipoles in 3-Dimension, 4-Dimension, and Other Dimensions
SASLOW, WM; Fulling, Stephen A.; Hu, Chia-Ren.
1985-01-01T23:59:59.000Z
-dimensional spaces where polar vec- tors have n components, spin has n (n ?1)/2 components. Moreover, although a rotation can make an arbitrary polar vector have only one noniero component, the same is not true for spin (and mag- netic field). In particular, for n... com- ponent we have derived the equation of motion for spin in n dimensions, and for n =4 we apply it to free Larmor precession, where we find two modes [at y(H~2+H34)]. Simple ferromagnets and spin glasses are also discussed for n=4. Since no true...
The Deng algorithm in higher dimensions
Y. Nyonyi; S. D. Maharaj; K. S. Govinder
2014-12-28T23:59:59.000Z
We extend an algorithm of Deng in spherically symmetric spacetimes to higher dimensions. We show that it is possible to integrate the generalised condition of pressure isotropy and generate exact solutions to the Einstein field equations for a shear-free cosmological model with heat flow in higher dimensions. Three new metrics are identified which contain results of four dimensions as special cases. We show graphically that the matter variables are well behaved and the speed of sound is causal.
String Universality in Six Dimensions
Vijay Kumar; Washington Taylor
2009-10-10T23:59:59.000Z
In six dimensions, cancellation of gauge, gravitational, and mixed anomalies strongly constrains the set of quantum field theories which can be coupled consistently to gravity. We show that for some classes of six-dimensional supersymmetric gauge theories coupled to gravity, the anomaly cancellation conditions are equivalent to tadpole cancellation and other constraints on the matter content of heterotic/type I compactifications on K3. In these cases, all consistent 6D supergravity theories have a realization in string theory. We find one example which may arise from a novel string compactification, and we identify a new infinite family of models satisfying anomaly factorization. We find, however, that this infinite family of models, as well as other infinite families of models previously identified by Schwarz are pathological. We suggest that it may be feasible to demonstrate that there is a string theoretic realization of all consistent six-dimensional supergravity theories which have Lagrangian descriptions with arbitrary gauge and matter content. We attempt to frame this hypothesis of string universality as a concrete conjecture.
Constructive Dimension and Turing Degrees Laurent Bienvenu #
Stephan, Frank
S with constructive Hausdor# dimension dimH (S) and constructive packing dimension dimP (S) is Turing equivalent to a sequence R with dimH (R) # (dim H (S)/dim P (S)) - #, for arbitrary # > 0. Furthermore, if dimP (S) > 0, then dimP (R) # 1 - #. The reduction thus serves as a randomness extractor that increases the algorithmic
Combinatorial Dimension in Fractional Cartesian Products
Gao, Frank
Combinatorial Dimension in Fractional Cartesian Products Ron Blei,1 Fuchang Gao2 1 Department of Mathematics, University of Connecticut, Storrs, Connecticut 06268; e-mail: blei@math.uconn.edu 2 Department? Correspondence to: R. Blei © 2004 Wiley Periodicals, Inc. 146 #12;COMBINATORIAL DIMENSION IN FRACTIONAL CARTESIAN
Deconstructing Dimensions Adventures in Theory Space
Nima Arkani-Hamed
2009-11-28T23:59:59.000Z
Theories of gravity and gauge forces in more than four dimensions offer a new paradigm for physics beyond the standard model. We present some of the most interesting recent ideas, and explain how signals for extra dimensions could appear in experiments at a linear e+e- collider.
Solar energy generation in three dimensions
Bernardi, Marco
We formulate, solve computationally and study experimentally the problem of collecting solar energy in three dimensions. We demonstrate that absorbers and reflectors can be combined in the absence of sun tracking to build ...
Dark Energy, Inflation and Extra Dimensions
Paul J. Steinhardt; Daniel Wesley
2008-12-07T23:59:59.000Z
We consider how accelerated expansion, whether due to inflation or dark energy, imposes strong constraints on fundamental theories obtained by compactification from higher dimensions. For theories that obey the null energy condition (NEC), we find that inflationary cosmology is impossible for a wide range of compactifications; and a dark energy phase consistent with observations is only possible if both Newton's gravitational constant and the dark energy equation-of-state vary with time. If the theory violates the NEC, inflation and dark energy are only possible if the NEC-violating elements are inhomogeneously distributed in thecompact dimensions and vary with time in precise synchrony with the matter and energy density in the non-compact dimensions. Although our proofs are derived assuming general relativity applies in both four and higher dimensions and certain forms of metrics, we argue that similar constraints must apply for more general compactifications.
On c-theorems in arbitrary dimensions
Arpan Bhattacharyya; Ling-Yan Hung; Kallol Sen; Aninda Sinha
2012-11-20T23:59:59.000Z
The dilaton action in 3+1 dimensions plays a crucial role in the proof of the a-theorem. This action arises using Wess-Zumino consistency conditions and crucially relies on the existence of the trace anomaly. Since there are no anomalies in odd dimensions, it is interesting to ask how such an action could arise otherwise. Motivated by this we use the AdS/CFT correspondence to examine both even and odd dimensional CFTs. We find that in even dimensions, by promoting the cut-off to a field, one can get an action for this field which coincides with the WZ action in flat space. In three dimensions, we observe that by finding an exact Hamilton-Jacobi counterterm, one can find a non-polynomial action which is invariant under global Weyl rescalings. We comment on how this finding is tied up with the F-theorem conjectures.
Secrecy coverage in two dimensions Amites Sarkar
Sarkar, Amites
Secrecy coverage in two dimensions Amites Sarkar Department of Mathematics Western Washington University Bellingham, WA 98225, USA Email: amites.sarkar@wwu.edu Abstract--Imagine a sensor network
Secrecy coverage in two dimensions Amites Sarkar
Sarkar, Amites
Secrecy coverage in two dimensions Amites Sarkar November 15, 2014 Abstract Working in the infinite, Bellingham, WA 98225, USA. Email: amites.sarkar@wwu.edu 1 #12;Svante Janson proved in 1986 [7] that coverage
Secrecy coverage in two dimensions Amites Sarkar
Sarkar, Amites
Secrecy coverage in two dimensions Amites Sarkar October 29, 2013 Abstract Working in the infinite, Western Washington University, Bellingham, WA 98225, USA. Email: amites.sarkar@wwu.edu 1 #12;Svante Janson
Constructive Dimension and Turing Degrees Laurent Bienvenu
Doty, David
sequence S with constructive Hausdorff dimension dimH(S) and constructive packing dimension dimP(S, if dimP(S) > 0, then dimP(R) 1 - . The reduction thus serves as a randomness extractor that increases sequence S (that is, dimH(S) = dimP(S)) such that dimH(S) > 0, the Turing degree of S has constructive
Breaking Parity Symmetry Using Extra Dimensions
R. N. Mohapatra; A. Pérez-Lorenzana
1999-11-17T23:59:59.000Z
We present a new way to break parity symmetry in left-right symmetric models using boundary conditions on the fields residing in the fifth dimension. We also discuss the connection between the limits on the size of extra dimensions and the scale of right handed symmetry breaking obtained from the analysis of neutrinoless double beta decay in the case where the righthanded gauge symmetry is in the bulk.
Large-dimension, high-ZT Thermoelectric Nanocomposites for High...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Large-dimension, high-ZT Thermoelectric Nanocomposites for High-Power High-efficiency Waste Heat Recovery for Electricity Generation Large-dimension, high-ZT Thermoelectric...
White Paper Societal Dimensions of Earth System Modeling
on Societal Dimensions of Earth System Modeling July 5, 2011 #12; 2 Executive Summary · A Societal Dimensions of Earth System Modeling workshop was held
Fractal Dimension Computation From Equal Mass Partitions
Shiozawa, Yui; Rouet, Jean-Louis
2015-01-01T23:59:59.000Z
While the numerical methods which utilizes partitions of equal-size, including the box-counting method, remain the most popular choice for computing the generalized dimension of multifractal sets, two mass- oriented methods are investigated by applying them to the one-dimensional generalized Cantor set. We show that both mass-oriented methods generate relatively good results for generalized dimensions for important cases where the box-counting method is known to fail. Both the strengths and limitations of the methods are also discussed.
Mauricio Cataldo; Alberto A. García
2014-05-15T23:59:59.000Z
In this paper we discuss the radiation equation of state $p=\\rho/2$ in (2+1)-dimensions. In (3+1)-dimensions the equation of state $p=\\rho/3$ may be used to describe either actual electromagnetic radiation (photons) as well as a gas of massless particles in a thermodynamic equilibrium (for example neutrinos). In this work it is shown that in the framework of (2+1)-dimensional Maxwell electrodynamics the radiation law $p=\\rho/2$ takes place only for plane waves, i.e. for $E = B$. Instead of the linear Maxwell electrodynamics, to derive the (2+1)-radiation law for more general cases with $E \
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 Delicious Rank EERE: Alternative Fuels Data Center HomeIdle Reduction WeightRebate - LADWPPublicE85 RetailNREL
The communication dimension of wind energy
McCalley, James D.
The communication dimension of wind energy: Challenges and opportunities #12;OPPORTUNITIES #12;Pew;1. Emergent anti-wind energy advocacy groups #12;2. A multi-faceted technical issue that is difficult to explain Wind energy Policy Science Engineering Ethics Public relations Others #12;3. Different audience
Similarity Dimension of a Glaciated Terrain
Jackson, Daniel R.
rate of movement. #12;Data Acquisition · The topography of a formerly glaciated surface the proportionality constant b from the previous equation. #12;Application to Topography · The topography of a region, it becomes possible to evaluate the length and similarity dimension of topography as Richardson
Large-N droplets in two dimensions
Dean Lee
2006-05-15T23:59:59.000Z
Using lattice effective field theory, we study the ground state binding energy of N distinct particles in two dimensions with equal mass interacting weakly via an attractive SU(N)-symmetric short range potential. We find that in the limit of zero range and large N, the ratio of binding energies B_{N}/B_{N-1} approaches the value 8.3(6).
Cosmological model with movement in fifth dimension
W. B. Belayev
2001-10-24T23:59:59.000Z
Presented cosmological model is 3D brane world sheet moved in extra dimension with variable scale factor. Analysis of the geodesic motion of the test particle gives settle explanation of the Pioneer effect. It is found that for considered metric the solution of the semi-classical Einstein equations with various parameters conforms to isotropic expanded and anisotropic stationary universe.
The Environmental Justice Dimensions of Climate Change
The Environmental Justice Dimensions of Climate Change Marie Lynn Miranda, Douglas A. Hastings to mitigate the severe impacts of climate change predicted to occur in the twenty-first century. Many with climate change. This study investigates the varying degrees to which developing and developed nations
DIMENSIONS of DISCOVERY Sponsored Program Awards
Ginzel, Matthew
DIMENSIONS of DISCOVERY Sponsored Program Awards May 2013 Office of the Vice President for ResearchFunds." Abu-Omar, Mahdi M; chemistry, from U.S. DepartmentofEnergy,$165,000,"OxoCata- lysts for the Conversion pathobiology, from PHS-NIH National Institute of Child Health and Human Development, $2,963, "Animal-Assisted
Geometrically induced magnetic catalysis and critical dimensions
Antonino Flachi; Kenji Fukushima; Vincenzo Vitagliano
2015-02-21T23:59:59.000Z
We discuss the combined effect of magnetic fields and geometry in interacting fermionic systems. At leading order in the heat-kernel expansion, the infrared singularity (that in flat space leads to the magnetic catalysis) is regulated by the chiral gap effect and the catalysis is deactivated by effect of the curvature. We discover that an infrared singularity may reappear from higher-order terms in the heat kernel expansion leading to a novel form of geometrically induced magnetic catalysis (absent in flat space). The dynamical mass squared is then modified not only due to the chiral gap effect by an amount proportional to the curvature, but also by a magnetic shift $\\propto (4-D)eB$ where $D$ represents the number of space-time dimensions. We argue that $D=4$ is a critical dimension across which the behaviour of the magnetic shift changes qualitatively.
Geometrically induced magnetic catalysis and critical dimensions
Flachi, Antonino; Vitagliano, Vincenzo
2015-01-01T23:59:59.000Z
We discuss the combined effect of magnetic fields and geometry in interacting fermionic systems. At leading order in the heat-kernel expansion, the infrared singularity (that in flat space leads to the magnetic catalysis) is regulated by the chiral gap effect and the catalysis is deactivated by effect of the curvature. We discover that an infrared singularity may reappear from higher-order terms in the heat kernel expansion leading to a novel form of geometrically induced magnetic catalysis (absent in flat space). The dynamical mass squared is then modified not only due to the chiral gap effect by an amount proportional to the curvature, but also by a magnetic shift $\\propto (4-D)eB$ where $D$ represents the number of space-time dimensions. We argue that $D=4$ is a critical dimension across which the behaviour of the magnetic shift changes qualitatively.
Geometrically induced magnetic catalysis and critical dimensions
Antonino Flachi; Kenji Fukushima; Vincenzo Vitagliano
2015-04-27T23:59:59.000Z
We discuss the combined effect of magnetic fields and geometry in interacting fermionic systems. At leading order in the heat-kernel expansion, the infrared singularity (that in flat space leads to the magnetic catalysis) is regulated by the chiral gap effect, and the catalysis is deactivated by the effect of the scalar curvature. We discover that an infrared singularity is found in higher-order terms that mix the magnetic field with curvature, and these lead to a novel form of geometrically induced magnetic catalysis. The dynamical mass squared is then modified not only due to the chiral gap effect by an amount proportional to the curvature, but also by a magnetic shift $\\propto (4-D)eB$, where $D$ represents the number of space-time dimensions. We argue that $D=4$ is a critical dimension across which the behavior of the magnetic shift changes qualitatively.
M(atrix)-Theory in Various Dimensions
David Berenstein; Richard Corrado
1997-02-14T23:59:59.000Z
We demonstrate the precise numerical correspondence between long range scattering of supergravitons and membranes in supergravity in the infinite momentum frame and in M(atrix)-Theory, both in 11 dimensions and for toroidal compactifications. We also identify wrapped membranes in terms of topological invariants of the vector bundles associated to the field theory description of compactified M(atrix)-Theory. We use these results to check the realization of T-duality in M(atrix)-Theory.
Codes and Supersymmetry in One Dimension
C. F. Doran; M. G. Faux; S. J. Gates Jr.; T. Hübsch; K. M. Iga; G. D. Landweber; R. L. Miller
2011-08-20T23:59:59.000Z
Adinkras are diagrams that describe many useful supermultiplets in D=1 dimensions. We show that the topology of the Adinkra is uniquely determined by a doubly even code. Conversely, every doubly even code produces a possible topology of an Adinkra. A computation of doubly even codes results in an enumeration of these Adinkra topologies up to N=28, and for minimal supermultiplets, up to N=32.
Effective Fractal Dimension in Computational Complexity and
have: Â computable by a finite automata dimFS Â computable in polynomial time dimp Â computable? E= DTIME(2n) DENSE= { L | n |Ln|>2n } dimp(E)=1 #12;Density of hard sets The p-dimension of sets-Hitchcock 2011] #12;Density of hard sets 1. Abundance result (dimp(E)=1) Most sets in E do not reduce to nondense
PACKING DIMENSIONS, TRANSVERSAL MAPPINGS AND GEODESIC FLOWS
JyvÃ¤skylÃ¤, University of
result for the packing dimension, dimp, of projected measures. They showed that if Âµ is a finite Borel measure on Rn , then (1.1) dimp PV Âµ = dimm Âµ for almost all V G(n, m), where dimm Âµ is a packing is the same for almost all projections, but it may happen that dimm Âµ dimp Âµ. The above results are "almost
Dimensional reduction without continuous extra dimensions
Chamseddine, Ali H. [American University of Beirut, Physics Department, Beirut, Lebanon and I.H.E.S. F-91440 Bures-sur-Yvette (France)] [American University of Beirut, Physics Department, Beirut, Lebanon and I.H.E.S. F-91440 Bures-sur-Yvette (France); Froehlich, J.; Schubnel, B. [ETHZ, Mathematics and Physics Departments, Zuerich (Switzerland)] [ETHZ, Mathematics and Physics Departments, Zuerich (Switzerland); Wyler, D. [Institute of Theoretical Physics, University of Zuerich (Switzerland)] [Institute of Theoretical Physics, University of Zuerich (Switzerland)
2013-01-15T23:59:59.000Z
We describe a novel approach to dimensional reduction in classical field theory. Inspired by ideas from noncommutative geometry, we introduce extended algebras of differential forms over space-time, generalized exterior derivatives, and generalized connections associated with the 'geometry' of space-times with discrete extra dimensions. We apply our formalism to theories of gauge- and gravitational fields and find natural geometrical origins for an axion- and a dilaton field, as well as a Higgs field.
Noncommutative Inspired Black Holes in Extra Dimensions
Rizzo, Thomas G.
2006-06-07T23:59:59.000Z
In a recent string theory motivated paper, Nicolini, Smailagic and Spallucci (NSS) presented an interesting model for a noncommutative inspired, Schwarzschild-like black hole solution in 4-dimensions. The essential effect of having noncommutative co-ordinates in this approach is to smear out matter distributions on a scale associated with the turn-on of noncommutativity which was taken to be near the 4-d Planck mass. In particular, NSS assumed that this smearing was essentially Gaussian. This energy scale is sufficiently large that in 4-d such effects may remain invisible indefinitely. Extra dimensional models which attempt to address the gauge hierarchy problem, however, allow for the possibility that the effective fundamental scale may not be far from {approx} 1 TeV, an energy regime that will soon be probed by experiments at both the LHC and ILC. In this paper we generalize the NSS model to the case where flat, toroidally compactified extra dimensions are accessible at the TeV-scale and examine the resulting modifications in black hole properties due to the existence of noncommutativity. We show that while many of the noncommutativity-induced black hole features found in 4-d by NSS persist, in some cases there can be significant modifications due the presence of extra dimensions. We also demonstrate that the essential features of this approach are not particularly sensitive to the Gaussian nature of the smearing assumed by NSS.
Carlos Castro; Alex Granik; M. S. El Naschie
2000-08-18T23:59:59.000Z
A Cantorian fractal spacetime, a family member of von Neumann's noncommutative geometry is introduced as a geometry underlying a new relativity theory which is similar to the relation between general relativity and Riemannian geometry. Based on this model and the new relativity theory an ensemble distribution of all the dimensions of quantum spacetime is derived with the help of Fermat grand theorem. The calculated average dimension is very close to the value of $4+\\phi^3 $ (where $\\phi$ is the golden mean) obtained by El Naschie on the basis of a different approach. It is shown that within the framework of the new relativity the cosmological constant problem is nonexistent, since the Universe self-organizes and self-tunes according to the renormalization group (RG) flow with respect to a local scaling microscopic arrow of time. This implies that the world emerged as a result of a non-equilibrium process of self-organized critical phenomena launched by vacuum fluctuations in Cantorian fractal spacetime $\\cal E^{\\infty}$. It is shown that we are living in a metastable vacuum and are moving towards a fixed point ($ D$ = 4+$\\phi^3$) of the RG. After reaching this point, a new phase transition will drive the universe to a quasi-crystal phase of the lower average dimension of $\\phi^3$.
DEFORMATION-BASED NONLINEAR DIMENSION REDUCTION: APPLICATIONS TO NUCLEAR MORPHOMETRY
Gordon, Geoffrey J.
DEFORMATION-BASED NONLINEAR DIMENSION REDUCTION: APPLICATIONS TO NUCLEAR MORPHOMETRY Gustavo K, contrary to common intuition, the most likely nuclear shape configuration is not symmetric. Index Terms-- Nuclear shape analysis, nonlinear, dimension reduction, image registration. 1. INTRODUCTION Under
Adena Rissman Assistant Professor, Human Dimensions of Ecosystem Management
Sheridan, Jennifer
Adena Rissman Assistant Professor, Human Dimensions of Ecosystem Management Department of Forest Professor: 2009-present Human Dimensions of Ecosystem Management Department of Forest and Wildlife Ecology, Integrative Graduate Education and Research Training (IGERT). "Novel ecosystems, rapid change, and no
Splitting a Complex of Convex Polytopes In Any Dimension*
Texas at Austin, University of
]. The main contributions of this approach atw (i) it c,an be applied to polyhedral complexes of any dimension
Dimension two vacuum condensates in gauge-invariant theories
D. V. Bykov; A. A. Slavnov
2005-05-11T23:59:59.000Z
Gauge dependence of the dimension two condensate in Abelian and non-Abelian Yang-Mills theory is investigated.
FRACTAL DIMENSION ESTIMATION: EMPIRICAL MODE DECOMPOSITION VERSUS WAVELETS
GonÃ§alves, Paulo
FRACTAL DIMENSION ESTIMATION: EMPIRICAL MODE DECOMPOSITION VERSUS WAVELETS Paulo GoncÂ¸alves INRIA, France. {firstname.lastname}@ens-lyon.fr ABSTRACT We address the problem of fractal dimension estimation motions. Index Terms-- fractal dimension, regularity exponents, wavelet transform, EMD 1. MOTIVATION
On the fractal dimension of the Duffing attractor
Mariusz Tarnopolski
2014-09-12T23:59:59.000Z
The box counting dimension $d_C$ and the correlation dimension $d_G$ change with the number of numerically generated points forming the attractor. At a sufficiently large number of points the fractal dimension tends to a finite value. The obtained values are $d_C\\approx 1.43$ and $d_G\\approx 1.38$.
Generalized dimensions of images of measures under Gaussian processes
Falconer, Kenneth
). The corresponding question for packing dimension dimP, where dimensions of images of sets can behave in a more Brownian motion, dimP X(E) = dimd P E a.s., where dims P E is the `packing dimension profile' of E
Fractal Dimension for Fractal Structures: A Hausdorff Approach
M. A. Sánchez-Granero; Manuel Fernández-Martínez
2010-07-22T23:59:59.000Z
This paper provides a new model to compute the fractal dimension of a subset on a generalized-fractal space. Recall that fractal structures are a perfect place where a new definition of fractal dimension can be given, so we perform a suitable discretization of the Hausdorff theory of fractal dimension. We also find some connections between our definition and the classical ones and also with fractal dimensions I & II (see http://arxiv.org/submit/0080421/pdf). Therefore, we generalize them and obtain an easy method in order to calculate the fractal dimension of strict self-similar sets which are not required to verify the open set condition.
NONLINEAR MODELS IN 2 +{epsilon} DIMENSIONS
Friedan, D.
1980-05-01T23:59:59.000Z
A generalization of the nonlinear ~ model is considered. The field takes values in a compact manifold M and the coupling is determined by a Riemannian metric on H. The model is renormalizable in 2 + ~ dimensions, the renormalization group acting on the infinite dimensional space of Riemannian metrics. Topological properties of the p-function and solutions of the fixed point equation R{sub ij}-?g{sub ij}=?{sub i}v{sub j}+?{sub j}v{sub i}, ?=±1 or 0, are discussed.
Interacting spin-2 fields in three dimensions
Afshar, Hamid R; Merbis, Wout
2015-01-01T23:59:59.000Z
Using the frame formulation of multi-gravity in three dimensions, we show that demanding the presence of secondary constraints which remove the Boulware-Deser ghosts restricts the possible interaction terms of the theory and identifies invertible frame field combinations whose effective metric may consistently couple to matter. The resulting ghost-free theories can be represented by theory graphs which are trees. In the case of three frame fields, we explicitly show that the requirement of positive masses and energies for the bulk spin-2 modes in AdS$_3$ is consistent with a positive central charge for the putative dual CFT$_2$.
Interacting spin-2 fields in three dimensions
Hamid R. Afshar; Eric A. Bergshoeff; Wout Merbis
2015-01-14T23:59:59.000Z
Using the frame formulation of multi-gravity in three dimensions, we show that demanding the presence of secondary constraints which remove the Boulware-Deser ghosts restricts the possible interaction terms of the theory and identifies invertible frame field combinations whose effective metric may consistently couple to matter. The resulting ghost-free theories can be represented by theory graphs which are trees. In the case of three frame fields, we explicitly show that the requirement of positive masses and energies for the bulk spin-2 modes in AdS$_3$ is consistent with a positive central charge for the putative dual CFT$_2$.
Shape Dynamics in 2+1 Dimensions
Timothy Budd; Tim Koslowski
2011-07-07T23:59:59.000Z
Shape Dynamics is a formulation of General Relativity where refoliation invariance is traded for local spatial conformal invariance. In this paper we explicitly construct Shape Dynamics for a torus universe in 2+1 dimensions through a linking gauge theory that ensures dynamical equivalence with General Relativity. The Hamiltonian we obtain is formally a reduced phase space Hamiltonian. The construction of the Shape Dynamics Hamiltonian on higher genus surfaces is not explicitly possible, but we give an explicit expansion of the Shape Dynamics Hamiltonian for large CMC volume. The fact that all local constraints are linear in momenta allows us to quantize these explicitly, and the quantization problem for Shape Dynamics turns out to be equivalent to reduced phase space quantization. We consider the large CMC-volume asymptotics of conformal transformations of the wave function. We then use the similarity of Shape Dynamics on the 2-torus with the explicitly constructible strong gravity (BKL) Shape Dynamics Hamiltonian in higher dimensions to suggest a quantization strategy for Shape Dynamics.
Physical Vacuum Properties and Internal Space Dimension
M. V. Gorbatenko; A. V. Pushkin
2004-09-25T23:59:59.000Z
The paper addresses matrix spaces, whose properties and dynamics are determined by Dirac matrices in Riemannian spaces of different dimension and signature. Among all Dirac matrix systems there are such ones, which nontrivial scalar, vector or other tensors cannot be made up from. These Dirac matrix systems are associated with the vacuum state of the matrix space. The simplest vacuum system realization can be ensured using the orthonormal basis in the internal matrix space. This vacuum system realization is not however unique. The case of 7-dimensional Riemannian space of signature 7(-) is considered in detail. In this case two basically different vacuum system realizations are possible: (1) with using the orthonormal basis; (2) with using the oblique-angled basis, whose base vectors coincide with the simple roots of algebra E_{8}. Considerations are presented, from which it follows that the least-dimension space bearing on physics is the Riemannian 11-dimensional space of signature 1(-)& 10(+). The considerations consist in the condition of maximum vacuum energy density and vacuum fluctuation energy density.
Quantum critical metals in $4-?$ dimensions
Gonzalo Torroba; Huajia Wang
2014-11-20T23:59:59.000Z
We study the quantum theory of a Fermi surface coupled to a gapless boson scalar in $D=4-\\epsilon$ spacetime dimensions as a simple model for non-Fermi liquids (NFL) near a quantum phase transition. Our analysis takes into account the full backreaction from Landau damping of the boson, and obtains an RG flow that proceeds through three distinct stages. Above the scale of Landau damping the Fermi velocity flows to zero, while the coupling evolves according to its classical dimension. Once damping becomes important, its backreaction leads to a crossover regime where dynamic and static damping effects compete and the fermion self-energy does not respect scaling. Below this crossover and having tuned the boson to criticality, the theory flows to a $z=3$ scalar interacting with a NFL. By increasing the number of bosonic flavors, the phase diagram near the quantum critical point interpolates between a superconducting dome fully covering the NFL behavior, and a phase where NFL effects become important first, before the onset of superconductivity. A generic prediction of the theory is that the Fermi velocity and quasiparticle residue vanish with a power-law $\\omega^\\epsilon$ as the fixed point is approached. These features may be useful for understanding some of the phenomenology of high $T_c$ materials in a systematic $\\epsilon$--expansion.
Extra dimensions, orthopositronium decay, and stellar cooling
Alexander Friedland; Maurizio Giannotti
2007-09-14T23:59:59.000Z
In a class of extra dimensional models with a warped metric and a single brane the photon can be localized on the brane by gravity only. An intriguing feature of these models is the possibility of the photon escaping into the extra dimensions. The search for this effect has motivated the present round of precision orthopositronium decay experiments. We point out that in this framework a photon in plasma should be metastable. We consider the astrophysical consequences of this observation, in particular, what it implies for the plasmon decay rate in globular cluster stars and for the core-collapse supernova cooling rate. The resulting bounds on the model parameter exceed the possible reach of orthopositronium experiments by many orders of magnitude.
The BCS - BEC Crossover In Arbitrary Dimensions
Zohar Nussinov; Shmuel Nussinov
2005-10-11T23:59:59.000Z
Cold atom traps and certain neutron star layers may contain fermions with separation much larger than the range of pair-wise potentials yet much shorter than the scattering length. Such systems can display {\\em universal} characteristics independent of the details of the short range interactions. In particular, the energy per particle is a fraction $\\xi$ of the Fermi energy of the free Fermion system. Our main result is that for space dimensions D smaller than two and larger than four a specific extension of this problem readily yields $\\xi=1$ for all $D \\le 2$ whereas $\\xi$ is rigorously non-positive (and potentially vanishing) for all $ D \\ge 4$. We discuss the D=3 case. A particular unjustified recipe suggests $\\xi=1/2$ in D=3.
Solar Energy Generation in Three Dimensions
Bernardi, Marco; Wan, Jin H; Villalon, Rachelle; Grossman, Jeffrey C
2011-01-01T23:59:59.000Z
Optimizing the conversion of solar energy to electricity is central to the World's future energy economy. Flat photovoltaic panels are commonly deployed in residential and commercial rooftop installations without sun tracking systems and using simple installation guidelines to optimize solar energy collection. Large-scale solar energy generation plants use bulky and expensive sun trackers to avoid cosine losses from photovoltaic panels or to concentrate sunlight with mirrors onto heating fluids.[1,2] However, none of these systems take advantage of the three-dimensional nature of our biosphere, so that solar energy collection largely occurs on flat structures in contrast with what is commonly observed in Nature.[3,4] Here we formulate, solve computationally and study experimentally the problem of collecting solar energy in three-dimensions.[5] We demonstrate that absorbers and reflectors can be combined in the absence of sun tracking to build three-dimensional photovoltaic (3DPV) structures that can generate ...
Improved Bounds on Universal Extra Dimensions
Thomas Flacke
2006-05-13T23:59:59.000Z
We report on recent constraints on models with a flat ``universal'' extra dimension in which all Standard Model fields propagate in the bulk. A significantly improved constraint on the compactification scale is obtained from the extended set of electroweak precision observables accurately measured at LEP1 and LEP2. We find a lower bound of 1/R > 700 (800) GeV at the 99% (95%) confidence level. Comparison of this constraint with the relic density of Kaluza-Klein dark matter for the Minimal UED model points towards the necessity of including non-minimal boundary terms which motivates studying alternative Kaluza-Klein dark matter candidates. Results for the one-loop induced magnetic dipole moment for Kaluza-Klein neutrino dark matter are presented. This talk is based on Phys.Rev.D73:095002,2006 and hep-ph/0601161.
Self-consistent bounces in two dimensions
Baacke, Juergen; Kevlishvili, Nina [Institut fuer Physik, Universitaet Dortmund, D-44221 Dortmund (Germany)
2005-01-15T23:59:59.000Z
We compute bounce solutions describing false vacuum decay in a {phi}{sup 4} model in two dimensions in the Hartree approximation, thus going beyond the usual one-loop corrections to the decay rate. We use zero energy mode functions of the fluctuation operator for the numerical computation of the functional determinant and the Green's function. We thus avoid the necessity of discretizing the spectrum, as it is necessary when one uses numerical techniques based on eigenfunctions. Regularization is performed in analogy of standard perturbation theory; the renormalization of the Hartree approximation is based on the two-particle point-irreducible scheme. The iteration towards the self-consistent solution is found to converge for some range of the parameters. Within this range we find the corrections to the leading one-loop approximation to be relatively small, not exceeding 1 order of magnitude in the total transition rate.
Constructive Dimension and Weak Truth-Table Degrees
Doty, David
dimension dimH(S) and constructive packing dimension dimP(S) is weak truth-table equivalent to a sequence R with dimH(R) dimH(S)/dimP(S) - , for arbitrary > 0. Furthermore, if dimP(S) > 0, then dimP(R) 1H(S) = dimP(S)) such that dimH(S) > 0, the wtt degree of S has constructive Hausdorff and packing dimension
Einstein's Dream of Unified Forces - extra dimensions | U.S....
Office of Science (SC) Website
hidden? What are the new particles associated with extra dimensions? Through the production of new particles that move in the extra space, the LHC experiments will have direct...
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 \
Generalized Klein-Gordon equations in d dimensions from supersymmetry
Bollini, C.G.; Giambiagi, J.J.
1985-12-15T23:59:59.000Z
The Wess-Zumino model is extended to higher dimensions, leading to a generalized Klein-Gordon equation whose propagator is computed in configuration space.
K-theoretic rigidity and slow dimension growth
2011-02-18T23:59:59.000Z
Oct 28, 2009 ... In fact, there are no simple separable nuclear stably finite C. ? ... fine locally finite nuclear dimension here; it is enough for us that separable.
Guiding center plasma models in three dimensions
Sugiyama, Linda E. [Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307 (United States)
2008-09-15T23:59:59.000Z
Guiding center plasma models describe the fast charged particle gyration around magnetic field lines by an angle coordinate, defined relative to local orthogonal coordinate axes (e{sub 1},e{sub 2},b=B/B) at each guiding center location. In three dimensions (3D), unlike uniform straight two-dimensional (2D) fields, geometrical effects make the small gyroradius expansion nonuniform in velocity phase space in first order O({rho}{sub i}/L). At second order, Hamiltonian and Lagrangian solutions may be undefined even when good magnetic flux surfaces exist; existence requires the magnetic field torsion {tau}=b{center_dot}{nabla}xb=0 and {tau}{sub g}{identical_to}b{center_dot}({nabla}e{sub 1}){center_dot}e{sub 2}=0, unless the magnetic field has a 2D symmetry, such as toroidal axisymmetry. Keeping complete 3D geometrical effects also requires the magnetic vector potential term to appear in the electric field at the same order as the electrostatic potential. These problems express properties of magnetic vector potentials, Lagrangians, and the curvature of manifolds, and have analogies to attempts to connect small scale Lagrangian theories to higher dimensional, large scale ones in the grand unification theories of physics.
Accelerating Universe from Extra Spatial Dimension
S. Chatterjee; A. Banerjee; Y. Z. Zhang
2005-09-28T23:59:59.000Z
We present a simple higher dimensional FRW type of model where the acceleration is apparently caused by the presence of the extra dimensions. Assuming an ansatz in the form of the deceleration parameter we get a class of solutions some of which shows the desirable feature of dimensional reduction as well as reasonably good physical properties of matter. Interestingly we do not have to invoke an extraneous scalar field or a cosmological constant to account for this acceleration. One argues that the terms containing the higher dimensional metric coefficients produces an extra negative pressure that apparently drives the inflation of the 4D space with an accelerating phase. It is further found that in line with the physical requirements our model admits of a decelerating phase in the early era along with an accelerating phase at present.Further the models asymptotically mimic a steady state type of universe although it starts from a big type of singularity. Correspondence to Wesson's induced matter theory is also briefly discussed and in line with it it is argued that the terms containing the higher dimensional metric coefficients apparently creates a negative pressure which drives the inflation of the 3-space with an accelerating phase.
Holographic c-theorems in arbitrary dimensions
Robert C. Myers; Aninda Sinha
2011-02-20T23:59:59.000Z
We re-examine holographic versions of the c-theorem and entanglement entropy in the context of higher curvature gravity and the AdS/CFT correspondence. We select the gravity theories by tuning the gravitational couplings to eliminate non-unitary operators in the boundary theory and demonstrate that all of these theories obey a holographic c-theorem. In cases where the dual CFT is even-dimensional, we show that the quantity that flows is the central charge associated with the A-type trace anomaly. Here, unlike in conventional holographic constructions with Einstein gravity, we are able to distinguish this quantity from other central charges or the leading coefficient in the entropy density of a thermal bath. In general, we are also able to identify this quantity with the coefficient of a universal contribution to the entanglement entropy in a particular construction. Our results suggest that these coefficients appearing in entanglement entropy play the role of central charges in odd-dimensional CFT's. We conjecture a new c-theorem on the space of odd-dimensional field theories, which extends Cardy's proposal for even dimensions. Beyond holography, we were able to show that for any even-dimensional CFT, the universal coefficient appearing the entanglement entropy which we calculate is precisely the A-type central charge.
Fractal dimension in dissipative chaotic scattering Jess M. Seoane,1,
Rey Juan Carlos, Universidad
Fractal dimension in dissipative chaotic scattering JesÃºs M. Seoane,1, * Miguel A. F. SanjuÃ¡n,1 on chaotic scattering is relevant to situations of physical interest. We inves- tigate how the fractal is thus the fractal dimension of the set of singularities. For nonhyperbolic scattering, it has been known
The Wavelet Dimension Function for Real Dilations and Dilations Admitting
Bownik, Marcin
The Wavelet Dimension Function for Real Dilations and Dilations Admitting non-MSF Wavelets Marcin Bownik and Darrin Speegle Abstract. The wavelet dimension function for arbitrary real dila- tions is defined and used to address several questions involving the existence of MRA wavelets and well
Interactive Dimensions in the Construction of Mental Representations for Text
Patel, Aniruddh D.
Interactive Dimensions in the Construction of Mental Representations for Text David N. Rapp be as critical to the construction of complex mental models as the discrete dimensions themselves. In the present a bead on Specify again. Incredibly, the horse was still rolling along. A pang of fear went through Woolf
Effects of Ultramicroelectrode Dimensions on the Electropolymerization of Polypyrrole
Fletcher, Benjamin L [ORNL; Fern, Jared T. [University of Tennessee, Knoxville (UTK); Rhodes, Kevin [University of Tennessee, Knoxville (UTK); McKnight, Timothy E [ORNL; Fowlkes, Jason Davidson [ORNL; Retterer, Scott T [ORNL; Keffer, David J. [University of Tennessee, Knoxville (UTK); Simpson, Michael L [ORNL; Doktycz, Mitchel John [ORNL
2009-01-01T23:59:59.000Z
Anode geometry can significantly affect the electrochemical synthesis of conductive polymers. Here, the effects of anode dimensions on the electropolymerization of pyrrole are investigated. Band microelectrodes were prepared with widths ranging from 2 to 500 {micro}m. The anode dimension has a significant effect on the resulting thickness of polymer film. The electropolymerization process deviates significantly from that predicted by simple mass transfer considerations when electrode dimensions are less than {approx}20 {micro}m. Polymer film thickness is thinner than expected when electrode dimensions become less than {approx}10 {micro}m. A simple mathematical model was derived to explain the observed effects of anode dimensions on the polymerization process. Simulation results confirm that diffusive loss of reaction intermediates accounts for the observed experimental trends. The described simulation facilitates understanding of the electropolymerization processes and approaches to the controlled deposition of polypyrrole, particularly at the submicron scale, for microelectromechanical systems and biomedical applications.
Giovanni Santostasi
2008-07-16T23:59:59.000Z
The Laser Interferometer Gravitational Observatory (LIGO) has recently reached the end of its fifth science run (S5), having collected more than a year worth of data. Analysis of the data is still ongoing but a positive detection of gravitational waves, while possible, is not realistically expected for most likely sources. This is particularly true for what concerns gravitational waves from known pulsars. In fact, even under the most optimistic (and not very realistic) assumption that all the pulsar's observed spin-down is due to gravitational waves, the gravitational wave strain at earth from all the known isolated pulsars (with the only notable exception of the Crab pulsar) would not be strong enough to be detectable by existing detectors. By August 2006, LIGO had produced enough data for a coherent integration capable to extract signal from noise that was weaker than the one expected from the Crab pulsar's spin-down limit. No signal was detected, but beating the spin-down limit is a considerable achievement for the LIGO Scientific Collaboration (LSC). It is customary to translate the upper limit on strain from a pulsar into a more astrophysically significant upper limit on ellipticity. Once the spin-down limit has been beaten, it is possible to release the constraint that all the spin-down is due to gravitational wave emission. A more complete model with diverse braking mechanisms can be used to set limits on several astrophysical parameters of the pulsar. This paper shows possible values of such parameters for the Crab pulsar given the current limit on gravitational waves from this neutron star.
is that the islands tend to buckle during anneal- ing to relieve stress, in addition to their lateral expansion Fig. 1Reduced buckling in one dimension versus two dimensions of a compressively strained film may permit undesirable roughening buckling of a compressively strained film. In this work, we
Dissipative hydrodynamics in 2+1 dimension
A. K. Chaudhuri
2006-05-25T23:59:59.000Z
In 2+1 dimension, we have simulated the hydrodynamic evolution of QGP fluid with dissipation due to shear viscosity. Comparison of evolution of ideal and viscous fluid, both initialised under the same conditions e.g. same equilibration time, energy density and velocity profile, reveal that the dissipative fluid evolves slowly, cooling at a slower rate. Cooling get still slower for higher viscosity. The fluid velocities on the otherhand evolve faster in a dissipative fluid than in an ideal fluid. The transverse expansion is also enhanced in dissipative evolution. For the same decoupling temperature, freeze-out surface for a dissipative fluid is more extended than an ideal fluid. Dissipation produces entropy as a result of which particle production is increased. Particle production is increased due to (i) extension of the freeze-out surface and (ii) change of the equilibrium distribution function to a non-equilibrium one, the last effect being prominent at large transverse momentum. Compared to ideal fluid, transverse momentum distribution of pion production is considerably enhanced. Enhancement is more at high $p_T$ than at low $p_T$. Pion production also increases with viscosity, larger the viscosity, more is the pion production. Dissipation also modifies the elliptic flow. Elliptic flow is reduced in viscous dynamics. Also, contrary to ideal dynamics where elliptic flow continues to increase with transverse momentum, in viscous dynamics, elliptic flow tends to saturate at large transverse momentum. The analysis suggest that initial conditions of the hot, dense matter produced in Au+Au collisions at RHIC, as extracted from ideal fluid analysis can be changed significantly if the QGP fluid is viscous.
The fractal dimension of the spectrum of quasiperiodical schrodinger operators
Laurent Marin
2012-02-20T23:59:59.000Z
We study the fractal dimension of the spectrum of a quasiperiodical Schrodinger operator associated to a sturmian potential. We consider potential defined with irrationnal number verifying a generic diophantine condition. We recall how shape and box dimension of the spectrum is linked to the irrational number properties. In the first place, we give general lower bound of the box dimension of the spectrum, true for all irrational numbers. In the second place, we improve this lower bound for almost all irrational numbers. We finally recall dynamical implication of the first bound.
Physical Interpretation of the 26 Dimensions of Bosonic String Theory
Frank D. Smith Jr
2002-07-15T23:59:59.000Z
The 26 dimensions of Closed Unoriented Bosonic String Theory are interpreted as the 26 dimensions of the traceless Jordan algebra J3(O)o of 3x3 Octonionic matrices, with each of the 3 Octonionic dimenisons of J3(O)o having the following physical interpretation: 4-dimensional physical spacetime plus 4-dimensional internal symmetry space; 8 first-generation fermion particles; 8 first-generation fermion anti-particles. This interpretation is consistent with interpreting the strings as World Lines of the Worlds of Many-Worlds Quantum Theory and the 26 dimensions as the degrees of freedom of the Worlds of the Many-Worlds.
Congestion pricing : policy dimensions, public rejection and impacts
Chingcuanco, Franco (Franco Felipe)
2014-01-01T23:59:59.000Z
This thesis makes three related contributions to the broad literature on congestion pricing. First, it examines three policy dimensions that underlie pricing: the economic arguments that motivate it, the technological ...
Wave propagation in periodic lattices with defects of smaller dimension
A. A. Kutsenko
2013-05-20T23:59:59.000Z
The procedure of evaluating of the spectrum for discrete periodic operators perturbed by operators of smaller dimensions is obtained. This result allows to obtain propagative, guided, localised spectra for different kind of physical operators on graphs with defects.
The Size of Compact Extra Dimensions from Blackbody Radiation Laws
Ramaton Ramos; Henrique Boschi-Filho
2014-04-28T23:59:59.000Z
In this work we generalize the Stefan-Boltzmann and Wien's displacement laws for a $D$-dimensional manifold composed by 4 non-compact dimensions and $D-4$ compact dimensions, $ R^{1,3}$ x $T^{D-4} $. The electromagnetic field is assumed to pervade all compact and non-compact dimensions. In particular, the total radiated power becomes $ R(T) = \\sigma_B T^4 + \\sigma_D (a) \\, T^D $, where $a$ is the size of the compact extra dimensions. For $D=10$, predicted from String Theory, and $D=11$, from M-Theory, the outcomes agree with available experimental data for $a$ as high as 2 x $10^{-7}$m.
STABILITY OF EQUILIBRIA IN ONE DIMENSION FOR DIBLOCK COPOLYMER EQUATION
Sander, Evelyn
STABILITY OF EQUILIBRIA IN ONE DIMENSION FOR DIBLOCK COPOLYMER EQUATION Olga Stulov Department for numerically. The various sets of the solutions of the linearized model were found by means of software AUTO
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.
The N = 8 superconformal bootstrap in three dimensions
Chester, Shai M.
We analyze the constraints imposed by unitarity and crossing symmetry on the four-point function of the stress-tensor multiplet of N=8 superconformal field theories in three dimensions. We first derive the superconformal ...
Constructive Dimension and Weak Truth-Table Degrees
Paris-Sud XI, Université de
infinite sequence S with construc- tive Hausdorff dimension dimH(S) and constructive packing dimension dimP(S. Furthermore, if dimP(S) > 0, then dimP(R) 1 - . The reduc- tion thus serves as a randomness extractor. It is also shown that, for any regular sequence S (that is, dimH(S) = dimP(S)) such that dimH(S) > 0, the wtt
Multipole moments for black objects in five dimensions
Kentaro Tanabe; Seiju Ohashi; Tetsuya Shiromizu
2010-11-19T23:59:59.000Z
In higher dimensions than four, conventional uniqueness theorem in asymptotically flat space-times does not hold, i.e., black objects can not be classified only by the mass, angular momentum and charge. In this paper, we define multipole moments for black objects and show that Myers-Perry black hole and black ring can be distinguished by quadrupole moments. This consideration gives us a new insight for the uniqueness theorem for black objects in higher dimensions.
Mass Generation and Related Issues from Exotic Higher Dimensions
M. Rojas; M. A. De Andrade; L. P. Colatto; J. L. Matheus-Valle; L. P. G. De Assis; J. A. Helayel-Neto
2011-11-09T23:59:59.000Z
The main purpose of this work is to show that massless Dirac equation formulated for non-interacting Majorana-Weyl spinors in higher dimensions, particularly in D=1+9 and D=5+5, can lead to an interpretation of massive Majorana and Dirac spinors in D=1+3. By adopting suitable representations of the Dirac matrices in higher dimensions, we pursue the investigation of which higher dimensional space-times and which mass-shell relation concerning massless Dirac equations in higher dimensions may induce massive spinors in D=1+3. The mixing of the chiral fermions in higher dimensions may induce a mechanism such that four massive Majorana fermions may show up and, at an appropriate limit an almost zero and a huge mass show up with corresponding left-handed and right-handed eigenstates. This mechanism, in a peculiar way, could reassess the See-Saw scheme associated to neutrino with Majorana-type masses. Remarkably the masses of the particles are fixed by the dimension decoupling/reduction scheme based on the mass Lorentz invariant term, where one set of the decoupled dimensions are the "target" coordinates frame and the other set of coordinates is the composing block of the mass term in lower dimensions. This proposal should allow us to understand the generation of hierarchies, such as the fourth generation, for the fermionic masses in D=1+3, or in lower dimensions in general, starting from the constraints between the energy and the momentum in D=n+n. For the initial D=5+5 Majorana-Weyl spinors framework using the Weyl representation to the Dirac matrices we observe an intriguing decomposition of space-time that result in two very equivalent D=1+4 massive spinors which mass term, in D=1+3 included, is originated from the remained/decoupled component and that could induce a Brane-World mechanism.
Cosmologically safe QCD axion as a present from extra dimension
Kawasaki, Masahiro; Yanagida, Tsutomu T
2015-01-01T23:59:59.000Z
We propose a QCD axion model where the origin of PQ symmetry and suppression of axion isocurvature perturbations are explained by introducing an extra dimension. Each extra quark-antiquark pair lives on branes separately to suppress PQ breaking operators. The size of the extra dimension changes after inflation due to an interaction between inflaton and a bulk scalar field, which implies that the PQ symmetry can be drastically broken during inflation to suppress undesirable axion isocurvature fluctuations.
V. D. Dzhunushaliev
1997-12-16T23:59:59.000Z
It is supposed that in our Universe with compactified extra dimensions (ED) the domains exist with noncompactified ED. Such domain can be a wormhole-like solution in multidimensional gravity (MD), located between two null surfaces. With the availability of compactification mechanism this MD domain can be joined on null surfaces with two black holes filled by gauge field. Solution of this kind in MD gravity on the principal bundle with structural group SU(3) is obtained. This solution is wormhole-like object located between two null surfaces $ds^2=0$. In some sense these solutions are dual to black holes: they are statical spherically symmetric solutions under null surfaces whereas black holes are statical spherically symmetric solutions outside of event horizon.
Fractal dimension of interstellar clouds: opacity and noise effects
Nestor Sanchez; Emilio J. Alfaro; Enrique Perez
2006-10-20T23:59:59.000Z
There exists observational evidence that the interstellar medium has a fractal structure in a wide range of spatial scales. The measurement of the fractal dimension (Df) of interstellar clouds is a simple way to characterize this fractal structure, but several factors, both intrinsic to the clouds and to the observations, may contribute to affect the values obtained. In this work we study the effects that opacity and noise have on the determination of Df. We focus on two different fractal dimension estimators: the perimeter-area based dimension (Dper) and the mass-size dimension (Dm). We first use simulated fractal clouds to show that opacity does not affect the estimation of Dper. However, Dm tends to increase as opacity increases and this estimator fails when applied to optically thick regions. In addition, very noisy maps can seriously affect the estimation of both Dper and Dm, decreasing the final estimation of Df. We apply these methods to emission maps of Ophiuchus, Perseus and Orion molecular clouds in different molecular lines and we obtain that the fractal dimension is always in the range 2.6 2.3) average fractal dimension for the interstellar medium, as traced by different chemical species.
Dimension of physical systems, information processing, and thermodynamics
Nicolas Brunner; Marc Kaplan; Anthony Leverrier; Paul Skrzypczyk
2014-12-18T23:59:59.000Z
We ask how quantum theory compares to more general physical theories from the point of view of dimension. To do so, we first give two model independent definition of the dimension of physical systems, based on measurements and on the capacity of storing information. While both definitions are equivalent in classical and quantum mechanics, they are in general different in generalized probabilistic theories. We discuss in detail the case of a theory known as 'boxworld', and show that such a theory features systems with a dimension mismatch. This dimension mismatch can be made arbitrarily large by using an amplification procedure. Furthermore, we show that the dimension mismatch of boxworld has strong consequences on its power for performing information-theoretic tasks, leading to the collapse of communication complexity and to the violation of information causality. Finally, we discuss the consequences of a dimension mismatch from the perspective of thermodynamics, and ask whether this effect could break Landauer's erasure principle and thus the second law.
HAUSDORFF DIMENSION, ANALYTIC SETS AND TRANSCENDENCE G. A. EDGAR AND CHRIS MILLER
Edgar, Gerald
HAUSDORFF DIMENSION, ANALYTIC SETS AND TRANSCENDENCE G. A. EDGAR any of* * Edgar [5], Falconer [7], Mattila [9] or [11] for details). From now on, "dimension
Svendborg Brakes | 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 onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof Energy 2,AUDITCalifornia Sector:Shrenik IndustriesState of
Multi-element probabilistic collocation method in high dimensions
Foo, Jasmine [Division of Applied Mathematics, Brown University, 182 George St., Box F, Providence, RI 02912 (United States); Karniadakis, George Em [Division of Applied Mathematics, Brown University, 182 George St., Box F, Providence, RI 02912 (United States)], E-mail: gk@dam.brown.edu
2010-03-01T23:59:59.000Z
We combine multi-element polynomial chaos with analysis of variance (ANOVA) functional decomposition to enhance the convergence rate of polynomial chaos in high dimensions and in problems with low stochastic regularity. Specifically, we employ the multi-element probabilistic collocation method MEPCM and so we refer to the new method as MEPCM-A. We investigate the dependence of the convergence of MEPCM-A on two decomposition parameters, the polynomial order {mu} and the effective dimension {nu}, with {nu}<
Mass Generation and Related Issues from Exotic Higher Dimensions
Rojas, M; Colatto, L P; Matheus-Valle, J L; De Assis, L P G; Helayel-Neto, J A
2011-01-01T23:59:59.000Z
The main purpose of this work is to show that massless Dirac equation formulated for non-interacting Majorana-Weyl spinors in higher dimensions, particularly in D=1+9 and D=5+5, can lead to an interpretation of massive Majorana and Dirac spinors in D=1+3. By adopting suitable representations of the Dirac matrices in higher dimensions, we pursue the investigation of which higher dimensional space-times and which mass-shell relation concerning massless Dirac equations in higher dimensions may induce massive spinors in D=1+3. The mixing of the chiral fermions in higher dimensions may induce a mechanism such that four massive Majorana fermions may show up and, at an appropriate limit an almost zero and a huge mass show up with corresponding left-handed and right-handed eigenstates. This mechanism, in a peculiar way, could reassess the See-Saw scheme associated to neutrino with Majorana-type masses. Remarkably the masses of the particles are fixed by the dimension decoupling/reduction scheme based on the mass Lore...
TASI Lectures on Supergravity and String Vacua in Various Dimensions
Washington Taylor
2011-04-14T23:59:59.000Z
These lectures aim to provide a global picture of the spaces of consistent quantum supergravity theories and string vacua in higher dimensions. The lectures focus on theories in the even dimensions 10, 8, and 6. Supersymmetry, along with with anomaly cancellation and other quantum constraints, places strong limitations on the set of physical theories which can be consistently coupled to gravity in higher-dimensional space-times. As the dimensionality of space-time decreases, the range of possible supergravity theories and the set of known string vacuum constructions expand. These lectures develop the basic technology for describing a variety of string vacua, including heterotic, intersecting brane, and F-theory compactifications. In particular, a systematic presentation is given of the basic elements of F-theory. In each dimension, we summarize the current state of knowledge regarding the extent to which supergravity theories not realized in string theory can be shown to be inconsistent.
Constraints on extra dimensions from precision molecular spectroscopy
Salumbides, E J; Gato-Rivera, B; Ubachs, W
2015-01-01T23:59:59.000Z
Accurate investigations of quantum level energies in molecular systems are shown to provide a test ground to constrain the size of compactified extra dimensions. This is made possible by the recent progress in precision metrology with ultrastable lasers on energy levels in neutral molecular hydrogen (H$_2$, HD and D$_2$) and the molecular hydrogen ions (H$_2^+$, HD$^+$ and D$_2^+$). Comparisons between experiment and quantum electrodynamics calculations for these molecular systems can be interpreted in terms of probing large extra dimensions, under which conditions gravity will become much stronger. Molecules are a probe of space-time geometry at typical distances where chemical bonds are effective, i.e. at length scales of an \\AA. Constraints on compactification radii for extra dimensions are derived within the Arkani-Hamed-Dimopoulos-Dvali framework, while constraints for curvature or brane separation are derived within the Randall-Sundrum framework. Based on the molecular spectroscopy of D$_2$ molecules an...
On the selection of dimension reduction techniques for scientific applications
Fan, Y J; Kamath, C
2012-02-17T23:59:59.000Z
Many dimension reduction methods have been proposed to discover the intrinsic, lower dimensional structure of a high-dimensional dataset. However, determining critical features in datasets that consist of a large number of features is still a challenge. In this paper, through a series of carefully designed experiments on real-world datasets, we investigate the performance of different dimension reduction techniques, ranging from feature subset selection to methods that transform the features into a lower dimensional space. We also discuss methods that calculate the intrinsic dimensionality of a dataset in order to understand the reduced dimension. Using several evaluation strategies, we show how these different methods can provide useful insights into the data. These comparisons enable us to provide guidance to a user on the selection of a technique for their dataset.
Fermions in odd space-time dimensions: back to basics
Bashir, A; Galicia, Ma. de Jesus Anguiano
2005-01-01T23:59:59.000Z
It is a well known feature of odd space-time dimensions $d$ that there exist two inequivalent fundamental representations $A$ and $B$ of the Dirac gamma matrices. Moreover, the parity transformation swaps the fermion fields living in $A$ and $B$. As a consequence, a parity invariant Lagrangian can only be constructed by incorporating both the representations. Based upon these ideas and contrary to long held belief, we show that in addition to a discrete exchange symmetry for the massless case, we can also define chiral symmetry provided the Lagrangian contains fields corresponding to both the inequivalent representations. We also study the transformation properties of the corresponding chiral currents under parity and charge conjugation operations. We work explicitly in 2+1 dimensions and later show how some of these ideas generalize to an arbitrary number of odd dimensions.
Fermions in odd space-time dimensions: back to basics
A. Bashir; Ma. de Jesus Anguiano Galicia
2005-02-09T23:59:59.000Z
It is a well known feature of odd space-time dimensions $d$ that there exist two inequivalent fundamental representations $A$ and $B$ of the Dirac gamma matrices. Moreover, the parity transformation swaps the fermion fields living in $A$ and $B$. As a consequence, a parity invariant Lagrangian can only be constructed by incorporating both the representations. Based upon these ideas and contrary to long held belief, we show that in addition to a discrete exchange symmetry for the massless case, we can also define chiral symmetry provided the Lagrangian contains fields corresponding to both the inequivalent representations. We also study the transformation properties of the corresponding chiral currents under parity and charge conjugation operations. We work explicitly in 2+1 dimensions and later show how some of these ideas generalize to an arbitrary number of odd dimensions.
Probing Large Extra Dimensions With IceCube
Arman Esmaili; O. L. G. Peres; Zahra Tabrizi
2014-12-02T23:59:59.000Z
In models with Large Extra Dimensions the smallness of neutrino masses can be naturally explained by introducing gauge singlet fermions which propagate in the bulk. The Kaluza-Klein modes of these fermions appear as towers of sterile neutrino states on the brane. We study the phenomenological consequences of this picture for the high energy atmospheric neutrinos. For this purpose we construct a detailed equivalence between a model with large extra dimensions and a (3 + n) scenario consisting of three active and n extra sterile neutrino states, which provides a clear intuitive understanding of Kaluza-Klein modes. Finally, we analyze the collected data of high energy atmospheric neutrinos by IceCube experiment and obtain bounds on the radius of extra dimensions.
Dark Energy from Casimir Energy on Noncommutative Extra Dimensions
S. Fabi; B. Harms; G. Karatheodoris
2006-07-20T23:59:59.000Z
We study the possibility that dark energy is a manifestation of the Casimir energy on extra dimensions with the topology of $S^2$. We consider our universe to be $M^4 \\times S^2$ and modify the geometry by introducing noncommutativity on the extra dimensions only, i.e. replacing $S^2$ with the fuzzy version $S_{F}^2$. We find the energy density as a function of the size of the representation $M+1$ of the algebra of $S_{F}^2$, and we calculate its value for the $M+1=2$ case. The value of the energy density turns out to be positive, i.e. provides dark energy, and the size of the extra dimensions agrees with the experimental limit. We also recover the correct commutative limit as the noncommutative parameter goes to zero.
RECURRENCE, DIMENSION AND ENTROPY AI-HUA FAN, DE-JUN FENG AND JUN WU
Fan, Ai-Hua
about the Hausdorff dimension dimH , the packing dimension dimP and the upper box dimension dimB (see [8 setting, topological entropy is related to dimension by 1 log m htop (E()) l dimH (E()) l dimP (E
A Critical "Dimension" in a Shell Model for Turbulence
Paolo Giuliani; Mogens H. Jensen; Victor Yakhot
2001-02-08T23:59:59.000Z
We investigate the GOY shell model within the scenario of a critical dimension in fully developed turbulence. By changing the conserved quantities, one can continuously vary an ``effective dimension'' between $d=2$ and $d=3$. We identify a critical point between these two situations where the flux of energy changes sign and the helicity flux diverges. Close to the critical point the energy spectrum exhibits a turbulent scaling regime followed by a plateau of thermal equilibrium. We identify scaling laws and perform a rescaling argument to derive a relation between the critical exponents. We further discuss the distribution function of the energy flux.
Bulk torsion fields in theories with large extra dimensions
Biswarup Mukhopadhyaya; Somasri Sen; Soumitra SenGupta
2002-04-25T23:59:59.000Z
We study the consequences of spacetime torsion coexisting with gravity in the bulk in scenarios with large extra dimensions. Having linked torsion with the Kalb-Ramond antisymmetric tensor field arising in string theories, we examine its artifacts on the visible 3-brane when the extra dimensions are compactified. It is found that while torsion would have led to parity violation in a 4-dimensional framework, all parity violating effects disappear on the visible brane when the torsion originates in the bulk. However, such a scenario is found to have characteristics of its own, some of which can be phenomenologically significant.
Fractal dimension analysis in a highly granular calorimeter
Ruan, M; Brient, J.C; Jeans, D; Videau, H
2015-01-01T23:59:59.000Z
The concept of “particle flow” has been developed to optimise the jet energy resolution by distinguishing the different jet components. A highly granular calorimeter designed for the particle flow algorithm provides an unprecedented level of detail for the reconstruction of calorimeter showers and enables new approaches to shower analysis. In this paper the measurement and use of the fractal dimension of showers is described. The fractal dimension is a characteristic number that measures the global compactness of the shower. It is highly dependent on the primary particle type and energy. Its application in identifying particles and estimating their energy is described in the context of a calorimeter designed for the International Linear Collider.
Yang-Mills like instantons in eight and seven dimensions
E. K. Loginov; E. D. Loginova
2014-10-10T23:59:59.000Z
We consider a gauge theory in which a nonassociative Moufang loop takes the place of a structure group. We construct Belavin-Polyakov-Schwartz-Tyupkin (BPST) and t'Hooft like instanton solutions of the gauge theory in seven and eight dimensions.
Fractal dimension and turbulence in Giant HII Regions
Caicedo-Ortiz, H E; López-Bonilla, J; Castañeda, H O
2015-01-01T23:59:59.000Z
We have measured the fractal dimensions of the Giant HII Regions Hubble X and Hubble V in NGC6822 using images obtained with the Hubble's Wide Field Planetary Camera 2 (WFPC2). These measures are associated with the turbulence observed in these regions, which is quantified through the velocity dispersion of emission lines in the visible. Our results suggest low turbulence behaviour.
Power: The New Dimension of Test Patrick GIRARD
Paris-Sud XI, UniversitÃ© de
1 Power: The New Dimension of Test Patrick GIRARD WRTLT 2008WRTLT 2008 ÂÂ SapporoSapporo -- Japan;2 1. Relevance of power during test 2. Main test power issues 3. Reducing test power by dedicated techniques 4. Low Power Design and its implications on test 5. One step to the future Outline lirmm-00820640
The Post Anachronism: The Temporal Dimension of Facebook Privacy
Reiter, Michael
The Post Anachronism: The Temporal Dimension of Facebook Privacy Lujo Bauer , Lorrie Faith Cranor the audience and emphasis of Facebook posts change over time. In a 63-participant longitudinal study, par- ticipants gave their audience and emphasis preferences for up to ten of their Facebook posts in the week
Independent Control of Multiple Magnetic Microrobots in Three Dimensions
Sitti, Metin
Independent Control of Multiple Magnetic Microrobots in Three Dimensions Eric Diller, Joshua method to independently control multiple sub-mm microrobots in three dimen- sions (3D) using magnetic of geometrically or magnetically distinct microrobots which assume different magnetization directions in a rotating
The Equivalence Principle as a Probe for Higher Dimensions
Paul S. Wesson
2006-01-17T23:59:59.000Z
Higher-dimensional theories of the kind which may unify gravitation with particle physics can lead to significant modifications of general relativity. In five dimensions, the vacuum becomes non-standard, and the Weak Equivalence Principle becomes a geometrical symmetry which can be broken, perhaps at a level detectable by new tests in space.
Looking into Higher Dimensions: Research with Joseph McMoneagle
Bryan, Ronald
by nuclear reactors can travel as far as 25 light- years in solid lead before being deflected. Another at nuclear distances, and see into higher dimensions. To "calibrate" McMoneagle, I asked him three things (in, if not the best: Joseph McMoneagle. [Joe has published four interesting and informative books on remote viewing
PACKING DIMENSION RESULTS FOR ANISOTROPIC GAUSSIAN RANDOM FIELDS
Xiao, Yimin
and GrX [0, 1]N are determined by the lower index of . Namely, dimP X [0, 1]N = min d, N , a.s. (1.5) and dimP GrX [0, 1]N = min N , N + (1 - )d , a.s., (1.6) where dimP E denotes the packing dimension of E
PACKING DIMENSION RESULTS FOR ANISOTROPIC GAUSSIAN RANDOM FIELDS
Paris-Sud XI, Université de
by the lower index of . Namely, dimP X [0, 1]N = min d, N , a.s. (1.5) and dimP GrX [0, 1]N = min N , N + (1 - )d , a.s., (1.6) where dimP E denotes the packing dimension o
Dimensioning hospital wards using the Erlang loss model Corresponding author
-2006. Finally, we demonstrate the efficiency of merging departments. Keywords: hospital resource allocationDimensioning hospital wards using the Erlang loss model Corresponding author: A.M. de Bruin (MSc of Sciences Department of Mathematics Assistant professor Optimization of Business Processes L. van Zanten
Upper bounds for multiphase composites in any dimension
Luis Silvestre
2010-10-12T23:59:59.000Z
We prove a rigorous upper bound for the effective conductivity of an isotropic composite made of several isotropic components in any dimension. This upper bound coincides with the Hashin Shtrikman bound when the volume ratio of all phases but any two vanish.
Top-kkk Preferences in High Dimensions Duke University
Agarwal, Pankaj K.
Top-kkk Preferences in High Dimensions Albert Yu Duke University syu@cs.duke.edu Pankaj K. Agarwal applications, users are interested only in a small num- ber (say, k) of "top" objects from a large set on preference top-k queries [9, 12, 13, 23, 38]. Motivated by applications in business analysis, Vlachou et al
Favors from Facebook Friends: Unpacking Dimensions of Social Capital
Michigan, University of
capital [5, 14, 19]. Social capital is a conceptual framework that considers the resources held by thoseFavors from Facebook Friends: Unpacking Dimensions of Social Capital Yumi Jung, Rebecca Gray]@umich.edu ABSTRACT Past research has demonstrated a link between perceptions of social capital and use of the popular
IEEE TRANSACTIONS ON IMAGE PROCESSING 1 Determining the Intrinsic Dimension
Damelin, Steven
chemical unmixing [1], extracting speech signals in a noisy line [2], unmixing minerals [3] and unmixingIEEEProof IEEE TRANSACTIONS ON IMAGE PROCESSING 1 Determining the Intrinsic Dimension is an important step in the spectral unmixing process and under- or overestimation of this number may lead
The 5th Dimension: Building Blocks for Smart Infrastructures
artifact. Obviously, since the books only pass the energy field of the reader for a few seconds, any formThe 5th Dimension: Building Blocks for Smart Infrastructures Marc Langheinrich ETH Zurich Institute example of such an interaction in 5D would be the following scenario: two "smart" (i.e., tagged) books
Biocompatible Force Sensor with Optical Readout and Dimensions of
Straight, Aaron
Biocompatible Force Sensor with Optical Readout and Dimensions of 6 nm3 Hari Shroff,,§ Bjo1rn M Received June 6, 2005 ABSTRACT We have developed a nanoscopic force sensor with optical readout. The sensor energy transfer. The sensor was calibrated between 0 and 20 pN using a combined magnetic tweezers
Singularity free stars in (2+1) dimensions
Farook Rahaman; Ayan Banerjee; Irina Radinschi; Sumita Banerjee; Soumendranath Ruz
2012-10-23T23:59:59.000Z
We present some new types of non-singular model for anisotropic stars with constant $\\Lambda $ and variable $\\Lambda$ based on the Krori and Barua (KB) metric in $(2+1)$ dimensions. The solutions obtained here satisfy all the regularity conditions and its simple analytical form helps us to study the various physical properties of the configuration.
PRIMITIVE ALGEBRAS WITH ARBITRARY GELFAND-KIRILLOV DIMENSION
Vishne, Uzi
(1), (1999), 151-158 1. Preliminaries Let A be an affine k-algebra. The Gelfand-Kirillov dimension [6 A is finite dimensional. Otherwise GKdim(A) 1, and by Bergman's gap theorem [3], ei- ther GKdim(A) = 1 (in
A procedure to Estimate the Fractal Dimension of Waveforms
Carlos Sevcik
2010-03-27T23:59:59.000Z
A method is described for calculating the approximate fractal dimension from a set of N values y sampled from a waveform between time zero and t. The waveform was subjected to a double linear transformation that maps it into a unit square.
Running Scaling Dimensions in Holographic Renormalization Group Flows
Wolfgang Mueck
2010-06-15T23:59:59.000Z
Holographic renormalization group flows can be interpreted in terms of effective field theory. Based on such an interpretation, a formula for the running scaling dimensions of gauge-invariant operators along such flows is proposed. The formula is checked for some simple examples from the AdS/CFT correspondence, but can be applied also in non-AdS/non-CFT cases.
Quantum Gravity in Three Dimensions from Higher-Spin Holography
Tan, Hai Siong
2013-01-01T23:59:59.000Z
Higher Spin Anti-de Sitter Gravity,” JHEP 1012, 007 (2010)gravity in three dimensions from the per- spective of higher-spin holography in anti-gravity in three dimen- sions in the framework of higher-spin holography in anti-
DIMENSIONS OF DISTRIBUTED LEADERSHIP IN THE SME CONTEXT
Mottram, Nigel
1 DIMENSIONS OF DISTRIBUTED LEADERSHIP IN THE SME CONTEXT Steve Kempster*, Jason Cope** and Ken IN THE SME CONTEXT Abstract. Entrepreneurial ventures are led as effectively by small teams as by individuals individual leadership within the SME context. The overlap between heroic individual leadership
MODELLING THE ONSET OF DYNAMIC Importance of the Vertical Dimension
Johansen, Tom Henning
block models of an elastic slider under dry friction. I apply AmontonsCoulomb friction at the block levelMODELLING THE ONSET OF DYNAMIC FRICTION Importance of the Vertical Dimension by JØRGEN TRØMBORG of the onset of dynamic friction. Optical methods give access to the sliding interface before and during
Sliced Coordinate Analysis for Effective Dimension Reduction and Nonlinear Extensions
Kwok, James Tin-Yau
regression; Re- producing kernels. 1. INTRODUCTION The notion of effective dimension reduction (EDR, Li 1991 for estimating the EDR space. Unlike principal component regression, which first applies principal component of an input vector by regressing the input vector against the corresponding output to form an EDR space
DISORDERED BOSE EINSTEIN CONDENSATES WITH INTERACTION IN ONE DIMENSION
Boyer, Edmond
DISORDERED BOSE EINSTEIN CONDENSATES WITH INTERACTION IN ONE DIMENSION ROBERT SEIRINGER, JAKOB- Pitaevskii regime. We prove that Bose Einstein condensation survives even a strong random potential with a high density of scatterers. The character of the wave func- tion of the condensate, however, depends
Liquid pair correlations in four spatial dimensions: Theory versus simulation
M. Heinen; J. Horbach; H. Löwen
2014-11-06T23:59:59.000Z
Using liquid integral equation theory, we calculate the pair correlations of particles that interact via a smooth repulsive pair potential in d = 4 spatial dimensions. We discuss the performance of different closures for the Ornstein-Zernike equation, by comparing the results to computer simulation data. Our results are of relevance to understand crystal and glass formation in high-dimensional systems.
Magnetic and Electric Black Holes in Arbitrary Dimension
Adil Belhaj; Pablo Diaz; Antonio segui
2009-06-02T23:59:59.000Z
In this work, we compare two different objects: electric black holes and magnetic black holes in arbitrary dimension. The comparison is made in terms of the corresponding moduli space and their extremal geometries. We treat parallelly the magnetic and the electric cases. Specifically, we discuss the gravitational solution of these spherically symmetric objects in the presence of a positive cosmological constant. Then, we find the bounded region of the moduli space allowing the existence of black holes. After identifying it in both the electric and the magnetic case, we calculate the geometry that comes out between the horizons at the coalescence points. Although the electric and magnetic cases are both very different (only dual in four dimensions), gravity solutions seem to clear up most of the differences and lead to very similar geometries.
Efficient Cluster Algorithm for Spin Glasses in Any Space Dimension
Zheng Zhu; Andrew J. Ochoa; Helmut G. Katzgraber
2015-01-22T23:59:59.000Z
Spin systems with frustration and disorder are notoriously difficult to study both analytically and numerically. While the simulation of ferromagnetic statistical mechanical models benefits greatly from cluster algorithms, these accelerated dynamics methods remain elusive for generic spin-glass-like systems. Here we present a cluster algorithm for Ising spin glasses that works in any space dimension and speeds up thermalization by several orders of magnitude at temperatures where thermalization is typically difficult. Our isoenergetic cluster moves are based on the Houdayer cluster algorithm for two-dimensional spin glasses and lead to a speedup over conventional state-of-the-art methods that increases with the system size. We illustrate the benefits of the isoenergetic cluster moves in two and three space dimensions, as well as the nonplanar Chimera topology found in the D-Wave quantum annealing machine.
Perturbative c-theorem in d-dimensions
Kazuya Yonekura
2013-01-15T23:59:59.000Z
We study perturbative behavior of free energies on a d-dimensional sphere S^d for theories with marginal interactions. The free energies are interpreted as the "dilaton effective action" with the dilaton having a nontrivial background vacuum expectation value. We compute the dependence of the free energies on the radius of the sphere by using dimensional regularization. It is shown that the first (second) derivative of the free energies in odd (even) dimensions with respect to the radius of the sphere are proportional to the square of the beta functions of coupling constants. The result is consistent with the c, F and a-theorems in two, three, four and six dimensions. The result is also used to rule out a large class of scale invariant theories which are not conformally invariant.
Borromean ground state of fermions in two dimensions
A. G. Volosniev; D. V. Fedorov; A. S. Jensen; N. T. Zinner
2014-08-29T23:59:59.000Z
The study of quantum mechanical bound states is as old as quantum theory itself. Yet, it took many years to realize that three-body borromean systems that are bound when any two-body subsystem is unbound are abundant in nature. Here we demonstrate the existence of borromean systems of spin-polarized (spinless) identical fermions in two spatial dimensions. The ground state with zero orbital (planar) angular momentum exists in a borromean window between critical two- and three-body strengths. The doubly degenerate first excited states of angular momentum one appears only very close to the two-body threshold. They are the lowest in a possible sequence of so-called super-Efimov states. While the observation of the super-Efimov scaling could be very difficult, the borromean ground state should be observable in cold atomic gases and could be the basis for producing a quantum gas of three-body states in two dimensions.
Global symmetries of Yang-Mills squared in various dimensions
Anastasiou, A; Hughes, M J; Nagy, S
2015-01-01T23:59:59.000Z
Tensoring two on-shell super Yang-Mills multiplets in dimensions $D\\leq 10$ yields an on-shell supergravity multiplet, possibly with additional matter multiplets. Associating a (direct sum of) division algebra(s) $\\mathbb{D}$ with each dimension $3\\leq D\\leq 10$ we obtain formulae for the algebras $\\mathfrak{g}$ and $\\mathfrak{h}$ of the U-duality group $G$ and its maximal compact subgroup $H$, respectively, in terms of the internal global symmetry algebras of each super Yang-Mills theory. We extend our analysis to include supergravities coupled to an arbitrary number of matter multiplets by allowing for non-supersymmetric multiplets in the tensor product.
Stable heteronuclear few-atom bound states in mixed dimensions
Yin Tao; Zhang Peng; Zhang Wei [Department of Physics, Renmin University of China, Beijing 100872 (China)
2011-11-15T23:59:59.000Z
We study few-body problems in mixed dimensions where two or three heavy atoms are trapped individually in parallel one-dimensional tubes or two-dimensional disks and a single light atom travels freely in three dimensions. Using the Born-Oppenheimer approximation, we find three- and four-body bound states for a broad parameter region. Specifically, the existence of trimer and tetramer states persists to the negative scattering length regime, where no two-body bound state is present. As pointed out by Y. Nishida in an earlier work [Phys. Rev. A 82, 011605(R) (2010)], these few-body bound states are stable against three-body recombination due to geometric separation. In addition, we find that the binding energy of the ground trimer and tetramer state reaches its maximum value when the scattering lengths are comparable to the separation between the low-dimensional traps.
The Fractal Dimension of the Spectrum of the Fibonacci Hamiltonian
David Damanik; Mark Embree; Anton Gorodetski; Serguei Tcheremchantsev
2007-05-02T23:59:59.000Z
We study the spectrum of the Fibonacci Hamiltonian and prove upper and lower bounds for its fractal dimension in the large coupling regime. These bounds show that as $\\lambda \\to \\infty$, $\\dim (\\sigma(H_\\lambda)) \\cdot \\log \\lambda$ converges to an explicit constant ($\\approx 0.88137$). We also discuss consequences of these results for the rate of propagation of a wavepacket that evolves according to Schr\\"odinger dynamics generated by the Fibonacci Hamiltonian.
Fractal Zeta Functions and Complex Dimensions of Relative Fractal Drums
Michel L. Lapidus; Goran Radunovi?; Darko Žubrini?
2014-11-17T23:59:59.000Z
The theory of 'zeta functions of fractal strings' has been initiated by the first author in the early 1990s, and developed jointly with his collaborators during almost two decades of intensive research in numerous articles and several monographs. In 2009, the same author introduced a new class of zeta functions, called `distance zeta functions', which since then, has enabled us to extend the existing theory of zeta functions of fractal strings and sprays to arbitrary bounded (fractal) sets in Euclidean spaces of any dimension. A natural and closely related tool for the study of distance zeta functions is the class of 'tube zeta functions', defined using the tube function of a fractal set. These three classes of zeta functions, under the name of 'fractal zeta functions', exhibit deep connections with Minkowski contents and upper box dimensions, as well as, more generally, with the complex dimensions of fractal sets. Further extensions include zeta functions of relative fractal drums, the box dimension of which can assume negative values, including minus infinity. We also survey some results concerning the existence of the meromorphic extensions of the spectral zeta functions of fractal drums, based in an essential way on earlier results of the first author on the spectral (or eigenvalue) asymptotics of fractal drums. It follows from these results that the associated spectral zeta function has a (nontrivial) meromorphic extension, and we use some of our results about fractal zeta functions to show the new fact according to which the upper bound obtained for the corresponding abscissa of meromorphic convergence is optimal. Finally, we conclude this survey article by proposing several open problems and directions for future research in this area.
PACKING-DIMENSION PROFILES AND FRACTIONAL BROWNIAN MOTION
Khoshnevisan, Davar
analytic set E RN and every integer 1 m N, (1.1) dimP (PV E) = DimmE for n,m-almost all V Gn,m, Date is the packing dimension dimP E. The principle aim of this note is to prove that (1.2) holds for all real numbers, 1985, Chapter 18). Xiao (1997) proved that for every analytic set E RN , (1.3) dimP X(E) = 1 H Dim
Auto-Concealment of Supersymmetry in Extra Dimensions
Savas Dimopoulos; Kiel Howe; John March-Russell; James Scoville
2014-12-02T23:59:59.000Z
In supersymmetric (SUSY) theories with extra dimensions the visible energy in sparticle decays can be significantly reduced and its energy distribution broadened, thus significantly weakening the present collider limits on SUSY. The mechanism applies when the lightest supersymmetric particle (LSP) is a bulk state-- e.g. a bulk modulino, axino, or gravitino-- the size of the extra dimensions larger than ~$10^{-14}$ cm, and for a broad variety of visible sparticle spectra. In such cases the lightest ordinary supersymmetric particle (LOSP), necessarily a brane-localised state, decays to the Kaluza-Klein (KK) discretuum of the LSP. This dynamically realises the compression mechanism for hiding SUSY as decays into the more numerous heavier KK LSP states are favored. We find LHC limits on right-handed slepton LOSPs evaporate, while LHC limits on stop LOSPs weaken to ~350-410 GeV compared to ~700 GeV for a stop decaying to a massless LSP. Similarly, for the searches we consider, present limits on direct production of degenerate first and second generation squarks drop to ~450 GeV compared to ~800 GeV for a squark decaying to a massless LSP. Auto-concealment typically works for a fundamental gravitational scale of $M_*$~10-100 TeV, a scale sufficiently high that traditional searches for signatures of extra dimensions are mostly avoided. If superpartners are discovered, their prompt, displaced, or stopped decays can also provide new search opportunities for extra dimensions with the potential to reach $M_*$~$10^9$ GeV. This mechanism applies more generally than just SUSY theories, pertaining to any theory where there is a discrete quantum number shared by both brane and bulk sectors.
Team Massachusetts Brings a Fourth Dimension to the Solar Decathlon
Broader source: Energy.gov [DOE]
Team Massachusetts is bringing a unique perspective to the Solar Decathlon this fall. You might say it is a fourth dimension because of the team’s newly constructed 4D Home. But it could also be argued that it is because the Massachusetts College of Art and Design and University of Massachusetts Lowell are collaborating for the team’s first entry into the biannual competition, and they’re both public institutions.
Zero point energy on extra dimension: Noncommutative Torus
S. Fabi; B. Harms; G. Karatheodoris
2007-04-25T23:59:59.000Z
In this paper we calculate the zero point energy density experienced by observers on M^4 due to a massless scalar field defined throughout M^4 x T^2_F, where T^2_F are fuzzy extra dimensions. Using the Green's function approach we calculate the energy density for the commutative torus and the fuzzy torus. We calculate then the energy density for the fuzzy torus using the Hamiltonian approach. Agreement is shown between Green's function and Hamiltonian approaches.
Bosonization in higher dimensions via noncommutative field theory
Alexios P. Polychronakos
2006-05-04T23:59:59.000Z
We propose the bosonization of a many-body fermion theory in D spatial dimensions through a noncommutative field theory on a (2D-1)-dimensional space. This theory leads to a chiral current algebra over the noncommutative space and reproduces the correct perturbative Hilbert space and excitation energies for the fermions. The validity of the method is demonstrated by bosonizing a two-dimensional gas of fermions in a harmonic trap.
Bosonization in Higher Dimensions via Noncommutative Field Theory
Polychronakos, Alexios P. [Physics Department, City College of the CUNY, New York, New York 10031 (United States)
2006-05-12T23:59:59.000Z
We propose the bosonization of a many-body fermion theory in D spatial dimensions through a noncommutative field theory on a (2D-1)-dimensional space. This theory leads to a chiral current algebra over the noncommutative space and reproduces the correct perturbative Hilbert space and excitation energies for the fermions. The validity of the method is demonstrated by bosonizing a two-dimensional gas of fermions in a harmonic trap.
Fractal dimensions of the galaxy distribution varying by steps?
Marie-Noelle Celerier; Reuben Thieberger
2005-04-20T23:59:59.000Z
The structure of the large scale distribution of the galaxies have been widely studied since the publication of the first catalogs. Since large redshift samples are available, their analyses seem to show fractal correlations up to the observational limits. The value of the fractal dimension(s) calculated by different authors have become the object of a large debate, as have been the value of the expected transition from fractality to a possible large scale homogeneity. Moreover, some authors have proposed that different scaling regimes might be discerned at different lenght scales. To go further on into this issue, we have applied the correlation integral method to the wider sample currently available. We therefore obtain a fractal dimension of the galaxy distribution which seems to vary by steps whose width might be related to the organization hierarchy observed for the galaxies. This result could explain some of the previous results obtained by other authors from the analyses of less complete catalogs and maybe reconcile their apparent discrepancy. However, the method applied here needs to be further checked, since it produces odd fluctuations at each transition scale, which need to be thoroughly explained.
HAUSDORFF DIMENSION, ANALYTIC SETS AND TRANSCENDENCE G. A. EDGAR AND CHRIS MILLER
Edgar, Gerald
HAUSDORFF DIMENSION, ANALYTIC SETS AND TRANSCENDENCE G. A. EDGAR AND CHRIS MILLER Abstract. Every of Edgar [5], Falconer [7], Mattila [9] or [11] for details). From now on, "dimension" means "Hausdorff
Burrow fractal dimension and foraging success in subterranean rodents: a simulation
Burrow fractal dimension and foraging success in subterranean rodents: a simulation S. C. Le Comber. Fractal dimension, which describes how a burrow explores the surrounding area in a way that is independent assumed that burrows of high fractal dimension will be associated with greater foraging success, this has
Texas at Austin. University of
Fractal dimension unscreened angles measured for radial viscous fingering Olivier Praud Harry, USA #Received November 2004; published July 2005# have examined fractal patterns formed injection experiments. fractal dimension D 0 of pattern large r / 1.70Â±0.02. Further, generalized dimensions D pattern
Co-dimension-two Grazing Bifurcations in Single-degree-of-freedom Impact Oscillators
Zhao, Xiaopeng
Co-dimension-two Grazing Bifurcations in Single-degree-of-freedom Impact Oscillators Phanikrishna paper, the transition be- tween two characteristically different co-dimension-one grazing bifurcation scenarios is found to be associated with the presence of certain co-dimension-two graz- ing bifurcation
DETERMINING THE FRACTAL DIMENSION OF A TIME SERIES WITH A NEURAL NET
Danon, Yaron
DETERMINING THE FRACTAL DIMENSION OF A TIME SERIES WITH A NEURAL NET MARK J. EMBRECHTS AND YARON and require expert interaction for interpreting the calculated fractal dimension. Artificial neural nets (ANN) offer a fast and elegant way to estimate the fractal dimension of a time series. A backpropagation net
Cosmology in One Dimension: Fractal Geometry, Power Spectra and Correlation
Bruce N. Miller; Jean-Louis Rouet
2010-12-08T23:59:59.000Z
Concentrations of matter, such as galaxies and galactic clusters, originated as very small density fluctuations in the early universe. The existence of galaxy clusters and super-clusters suggests that a natural scale for the matter distribution may not exist. A point of controversy is whether the distribution is fractal and, if so, over what range of scales. One-dimensional models demonstrate that the important dynamics for cluster formation occur in the position-velocity plane. Here the development of scaling behavior and multifractal geometry is investigated for a family of one-dimensional models for three different, scale-free, initial conditions. The methodology employed includes: 1) The derivation of explicit solutions for the gravitational potential and field for a one-dimensional system with periodic boundary conditions (Ewald sums for one dimension); 2) The development of a procedure for obtaining scale-free initial conditions for the growing mode in phase space for an arbitrary power-law index; 3) The evaluation of power spectra, correlation functions, and generalized fractal dimensions at different stages of the system evolution. It is shown that a simple analytic representation of the power spectra captures the main features of the evolution, including the correct time dependence of the crossover from the linear to nonlinear regime and the transition from regular to fractal geometry. A possible physical mechanism for understanding the self-similar evolution is introduced. It is shown that hierarchical cluster formation depends both on the model and the initial power spectrum. Under special circumstances a simple relation between the power spectrum, correlation function, and correlation dimension in the highly nonlinear regime is confirmed.
Method of forming cavitated objects of controlled dimension
Anderson, P.R.; Miller, W.J.
1981-02-11T23:59:59.000Z
A method is disclosed of controllably varying the dimensions of cavitated objects such as hollow spherical shells wherein a precursor shell is heated to a temperature above the shell softening temperature in an ambient atmosphere wherein the ratio of gases which are permeable through the shell wall at that temperature to gases which are impermeable through the shell wall is substantially greater than the corresponding ratio for gases contained within the precursor shell. As the shell expands, the partial pressures of permeable gases internally and externally of the shell approach and achieve equilibrium, so that the final shell size depends solely upon the difference in impermeable gas partial pressures and shell surface tension.
Fractal Dimensions for Continuous Time Random Walk Limits
Mark M. Meerschaert; Erkan Nane; Yimin Xiao
2011-02-03T23:59:59.000Z
In a continuous time random walk (CTRW), each random jump follows a random waiting time. CTRW scaling limits are time-changed processes that model anomalous diffusion. The outer process describes particle jumps, and the non-Markovian inner process (or time change) accounts for waiting times between jumps. This paper studies fractal properties of the sample functions of a time-changed process, and establishes some general results on the Hausdorff and packing dimensions of its range and graph. Then those results are applied to CTRW scaling limits.
Model Independence in Two Dimensions and Polarized Cold Dipolar Molecules
Volosniev, A. G.; Fedorov, D. V.; Jensen, A. S.; Zinner, N. T. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark)
2011-06-24T23:59:59.000Z
We calculate the energy and wave functions of two particles confined to two spatial dimensions interacting via arbitrary anisotropic potentials with negative or zero net volume. The general rigorous analytic expressions are given in the weak coupling limit where universality or model independence are approached. The monopole part of anisotropic potentials is crucial in the universal limit. We illustrate the universality with a system of two arbitrarily polarized cold dipolar molecules in a bilayer. We discuss the transition to universality as a function of polarization and binding energy and compare analytic and numerical results obtained by the stochastic variational method. The universal limit is essentially reached for experimentally accessible strengths.
Compton Scattering at the NLC and Large Extra Dimensions
Hooman Davoudiasl
1999-09-23T23:59:59.000Z
We study Compton scattering, gamma e -> gamma e, in the context of the recent proposal for Weak Scale Quantum Gravity (WSQG) with large extra dimensions. It is shown that, with an ultraviolet cutoff $M_S \\sim 1$ TeV for the effective gravity theory, the cross section for this process at the Next Linear Collider (NLC) deviates from the prediction of the Standard Model significantly. Our results suggest that, for typical proposed NLC energies and luminosities, WSQG can be tested in the range 4 TeV$\\lsim M_S \\lsim$ 16 TeV, making gamma e -> gamma e an important test channel.
Radion stabilization from the vacuum on flat extra dimensions
Santos, Eli [Departamento de Fisica, Universidad Autonoma Metropolitana, Apartado Postal 55-534, C. P. 09340 Mexico, D.F. (Mexico); Secretaria Academica de Fisica y Matematicas, Fac. de Ingenieria, Universidad Autonoma de Chiapas, Calle 4a. Oriente, Norte 1428, 29000 Tuxtla Gutierrez, Chiapas (Mexico); Perez-Lorenzana, A. [Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados del I.P.N., Apartado Postal 14-740, 07000, Mexico, D.F. (Mexico); Pimentel, Luis O. [Departamento de Fisica, Universidad Autonoma Metropolitana, Apartado Postal 55-534, C. P. 09340 Mexico, D.F. (Mexico)
2008-01-15T23:59:59.000Z
Volume stabilization in models with flat extra dimensions could follow from vacuum energy residing in the bulk when translational invariance is spontaneously broken. We study a simple toy model that exemplifies this mechanism which considers a massive scalar field with nontrivial boundary conditions at the end points of the compact space, and includes contributions from brane and bulk cosmological constants. We perform our analysis in the conformal frame where the radion field, associated with volume variations, is defined, and present a general strategy for building stabilization potentials out of those ingredients. We also provide working examples for the interval and the T{sup n}/Z{sub 2} orbifold configuration.
Statistical Mechanics of Kinks in (1+1)-Dimensions
Francis J. Alexander; Salman Habib
1992-12-09T23:59:59.000Z
We investigate the thermal equilibrium properties of kinks in a classical $\\phi^4$ field theory in $1+1$ dimensions. The distribution function, kink density, and correlation function are determined from large scale simulations. A dilute gas description of kinks is shown to be valid below a characteristic temperature. A double Gaussian approximation to evaluate the eigenvalues of the transfer operator enables us to extend the theoretical analysis to higher temperatures where the dilute gas approximation fails. This approach accurately predicts the temperature at which the kink description breaks down.
Search for universal extra dimensions in ppbar collisions
Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; /Oklahoma U.; Acharya, Bannanje Sripath; /Tata Inst.; Adams, Mark Raymond; /Illinois U., Chicago; Adams, Todd; /Florida State U.; Alexeev, Guennadi D.; /Dubna, JINR; Alkhazov, Georgiy D.; /St. Petersburg, INP; Alton, Andrew K.; /Michigan U. /Augustana Coll., Sioux Falls; Alverson, George O.; /Northeastern U.; Aoki, Masato; /Fermilab; Askew, Andrew Warren; /Florida State U. /Stockholm U.
2011-12-01T23:59:59.000Z
We present a search for Kaluza-Klein (KK) particles predicted by models with universal extra dimensions (UED) using a data set corresponding to an integrated luminosity of 7.3 fb{sup -1}, collected by the D0 detector at a p{bar p} center of mass energy of 1.96 TeV. The decay chain of KK particles can lead to a final state with two muons of the same charge. This signature is used to set a lower limit on the compactification scale of R{sup -1} > 260 GeV in a minimal UED model.
Zero point energy on extra dimensions: Noncommutative torus
Fabi, S.; Harms, B.; Karatheodoris, G. [Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, Alabama 35487-0324 (United States)
2007-09-15T23:59:59.000Z
In this paper we calculate the zero point energy density experienced by observers on M{sup 4} due to a massless scalar field defined throughout M{sup 4}xT{sub F}{sup 2}, where T{sub F}{sup 2} are fuzzy extra dimensions. Using the Green's function approach we calculate the energy density for the commutative torus and the fuzzy torus. We also calculate the energy density for the fuzzy torus using the Hamiltonian approach. Agreement is shown between the Green's function and Hamiltonian approaches.
The Running coupling BFKL anomalous dimensions and splitting functions.
Thorne, Robert S
2 2 + 30.72?¯50? ) . (2.36) 14 This contribution to the splitting function for t = 6 and is shown in fig. 6.a. Note that because of the truncation of GE(N, t), beyond 6th order the expression for PLOgg (?, ?s(Q2)) is not what one would really get... .K. Abstract I explicitly calculate the anomalous dimensions and splitting functions governing the Q2 evolu- tion of the parton densities and structure functions which result from the running coupling BFKL equation at LO, i.e. I perform a resummation in powers...
Near field optical probe for critical dimension measurements
Stallard, B.R.; Kaushik, S.
1999-05-18T23:59:59.000Z
A resonant planar optical waveguide probe for measuring critical dimensions on an object in the range of 100 nm and below is disclosed. The optical waveguide includes a central resonant cavity flanked by Bragg reflector layers with input and output means at either end. Light is supplied by a narrow bandwidth laser source. Light resonating in the cavity creates an evanescent electrical field. The object with the structures to be measured is translated past the resonant cavity. The refractive index contrasts presented by the structures perturb the field and cause variations in the intensity of the light in the cavity. The topography of the structures is determined from these variations. 8 figs.
Method of forming cavitated objects of controlled dimension
Anderson, Paul R. (Toledo, OH); Miller, Wayne J. (Ann Arbor, MI)
1982-01-01T23:59:59.000Z
A method of controllably varying the dimensions of cavitated objects such as hollow spherical shells wherein a precursor shell is heated to a temperature above the shell softening temperature in an ambient atmosphere wherein the ratio of gases which are permeable through the shell wall at that temperature to gases which are impermeable through the shell wall is substantially greater than the corresponding ratio for gases contained within the precursor shell. As the shell expands, the partial pressures of permeable gases internally and externally of the shell approach and achieve equilibrium, so that the final shell size depends solely upon the difference in impermeable gas partial pressures and shell surface tension.
Explicit Supersymmetry Breaking on Boundaries of Warped Extra Dimensions
Hall, Lawrence J.; Nomura, Yasunori; Okui, Takemichi; Oliver, Steven J.
2003-02-25T23:59:59.000Z
Explicit supersymmetry breaking is studied in higher dimensional theories by having boundaries respect only a subgroup of the bulk symmetry. If the boundary symmetry is the maximal subgroup allowed by the boundary conditions imposed on the fields, then the symmetry can be consistently gauged; otherwise gauging leads to an inconsistent theory. In a warped fifth dimension, an explicit breaking of all bulk supersymmetries by the boundaries is found to be inconsistent with gauging; unlike the case of flat 5D, complete supersymmetry breaking by boundary conditions is not consistent with supergravity. Despite this result, the low energy effective theory resulting from boundary supersymmetry breaking becomes consistent in the limit where gravity decouples, and such models are explored in the hope that some way of successfully incorporating gravity can be found. A warped constrained standard model leads to a theory with one Higgs boson with mass expected close to the experimental limit. A unified theory in a warped fifth dimension is studied with boundary breaking of both SU(5) gauge symmetry and supersymmetry. The usual supersymmetric predictionfor gauge coupling unification holds even though the TeV spectrum is quite unlike the MSSM. Such a theory may unify matter and Higgs in the same SU(5) hypermultiplet.
Black holes with gravitational hair in higher dimensions
Anabalon, Andres [Departamento de Ciencias Facultad de Artes Liberales, Facultad de Ingenieria y Ciencias, Universidad Adolfo Ibanez, Vina Del Mar (Chile); Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1 D-14476 Golm (Germany); Canfora, Fabrizio [Centro de Estudios Cientificos (CECS), Casilla 1469 Valdivia (Chile); Giacomini, Alex; Oliva, Julio [Instituto de Ciencias Fisicas y Matematicas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia (Chile)
2011-10-15T23:59:59.000Z
A new class of vacuum black holes for the most general gravity theory leading to second order field equations in the metric in even dimensions is presented. These space-times are locally anti-de Sitter in the asymptotic region, and are characterized by a continuous parameter that does not enter in the conserve charges, nor it can be reabsorbed by a coordinate transformation: it is therefore a purely gravitational hair. The black holes are constructed as a warped product of a two-dimensional space-time, which resembles the r-t plane of the Banados-Teitelboim-Zanelli black hole, times a warp factor multiplying the metric of a D-2-dimensional Euclidean base manifold, which is restricted by a scalar equation. It is shown that all the Noether charges vanish. Furthermore, this is consistent with the Euclidean action approach: even though the black hole has a finite temperature, both the entropy and the mass vanish. Interesting examples of base manifolds are given in eight dimensions which are products of Thurston geometries, giving then a nontrivial topology to the black hole horizon. The possibility of introducing a torsional hair for these solutions is also discussed.
Deformations of infrared-conformal theories in two dimensions
Oscar Akerlund; Philippe de Forcrand
2014-10-05T23:59:59.000Z
We study two exactly solvable two-dimensional conformal models, the critical Ising model and the Sommerfield model, on the lattice. We show that finite-size effects are important and depend on the aspect ratio of the lattice. In particular, we demonstrate how to obtain the correct massless behavior from an infinite tower of finite-size-induced masses and show that it is necessary to first take the cylindrical geometry limit in order to get correct results. In the Sommerfield model we also introduce a mass deformation to measure the mass anomalous dimension, $\\gamma_m$. We find that the explicit scale breaking of the lattice setup induces corrections which must be taken into account in order to reproduce $\\gamma_m$ at the infrared fixed point. These results can be used to improve the methodology in the search for the conformal window in QCD-like theories with many flavors.
Brane solutions of a spherical sigma model in six dimensions
Hyun Min Lee; Antonios Papazoglou
2004-11-16T23:59:59.000Z
We explore solutions of six dimensional gravity coupled to a non-linear sigma model, in the presence of co-dimension two branes. We investigate the compactifications induced by a spherical scalar manifold and analyze the conditions under which they are of finite volume and singularity free. We discuss the issue of single-valuedness of the scalar fields and provide some special embedding of the scalar manifold to the internal space which solves this problem. These brane solutions furnish some self-tuning features, however they do not provide a satisfactory explanation of the vanishing of the effective four dimensional cosmological constant. We discuss the properties of this model in relation with the self-tuning example based on a hyperbolic sigma model.
Decay of Graviton Condensates and their Generalizations in Arbitrary Dimensions
Florian Kuhnel; Bo Sundborg
2014-09-30T23:59:59.000Z
Classicalons are self-bound classical field configurations, which include black holes in General Relativity. In quantum theory, they are described by condensates of many soft quanta. In this work, their decay properties are studied in arbitrary dimensions. It is found that generically the decays of other classicalons are enhanced compared to pure graviton condensates, ie. black holes. The evaporation of higher dimensional graviton condensates turns out to match Hawking radiation solely due to non-linearites captured by the classicalon picture. Although less stable than black holes, all self-bound condensates are shown to be stable in the limit of large mass. Like for black holes, the effective coupling always scales as the inverse of the number of constituents, indicating that these systems are at critical points of quantum phase transitions. Consequences for cosmology, astro- and collider physics are briefly discussed.
Inhomogeneous Cooling of the Rough Granular Gas in Two Dimensions
Sudhir N. Pathak; Dibyendu Das; R. Rajesh
2014-07-03T23:59:59.000Z
We study the inhomogeneous clustered regime of a freely cooling granular gas of rough particles in two dimensions using large-scale event driven simulations and scaling arguments. During collisions, rough particles dissipate energy in both the normal and tangential directions of collision. In the inhomogeneous regime, translational kinetic energy and the rotational energy decay with time $t$ as power-laws $t^{-\\theta_T}$ and $t^{-\\theta_R}$. We numerically determine $\\theta_T \\approx 1$ and $\\theta_R \\approx 1.6$, independent of the coefficients of restitution. The inhomogeneous regime of the granular gas has been argued to be describable by the ballistic aggregation problem, where particles coalesce on contact. Using scaling arguments, we predict $\\theta_T=1$ and $\\theta_R=1$ for ballistic aggregation, $\\theta_R$ being different from that obtained for the rough granular gas. Simulations of ballistic aggregation with rotational degrees of freedom are consistent with these exponents.
Accident at Three Mile Island: the human dimensions
Sills, D.L.; Wolf, C.P.; Shelanski, V.B. (eds.)
1982-01-01T23:59:59.000Z
A separate abstract was prepared for each of the 19 chapters, divided according to the following Parts: (1) Public Perceptions of Nuclear Energy; (2) Local Responses to Nuclear Plants; (3) Institutional Responsibilities for Nuclear Energy; (4) The Interaction of Social and Technical Systems; and (5) Implications for Public Policy. All of the abstracts will appear in Energy Abstracts for Policy Analysis (EAPA); three will appear in Energy Research Abstracts (ERA). At the request of the President's Commission on the Accident at Three Mile Island (the Kemeny Commission), the Social Science Research Council commissioned social scientists to write a series of papers on the human dimensions of the event. This volume includes those papers, in revised and expanded form, and a comprehensive bibliography of published and unpublished social science research on the accident and its aftermath.
Conserved Quasilocal Quantities and General Covariant Theories in Two Dimensions
W. Kummer; P. Widerin
1995-02-15T23:59:59.000Z
General matterless--theories in 1+1 dimensions include dilaton gravity, Yang--Mills theory as well as non--Einsteinian gravity with dynamical torsion and higher power gravity, and even models of spherically symmetric d = 4 General Relativity. Their recent identification as special cases of 'Poisson--sigma--models' with simple general solution in an arbitrary gauge, allows a comprehensive discussion of the relation between the known absolutely conserved quantities in all those cases and Noether charges, resp. notions of quasilocal 'energy--momentum'. In contrast to Noether like quantities, quasilocal energy definitions require some sort of 'asymptotics' to allow an interpretation as a (gauge--independent) observable. Dilaton gravitation, although a little different in detail, shares this property with the other cases. We also present a simple generalization of the absolute conservation law for the case of interactions with matter of any type.
Massive "spin-2" theories in arbitrary $D \\ge 3$ dimensions
D. Dalmazi; A. L. R. dos Santos; E. L. Mendonça
2014-08-28T23:59:59.000Z
Here we show that in arbitrary dimensions $D\\ge 3$ there are two families of second order Lagrangians describing massive "spin-2" particles via a nonsymmetric rank-2 tensor. They differ from the usual Fierz-Pauli theory in general. At zero mass one of the families is Weyl invariant. Such massless theory has no particle content in $D=3$ and gives rise, via master action, to a dual higher order (in derivatives) description of massive spin-2 particles in $D=3$ where both the second and the fourth order terms are Weyl invariant, contrary to the linearized New Massive Gravity. However, only the fourth order term is invariant under arbitrary antisymmetric shifts. Consequently, the antisymmetric part of the tensor $e_{[\\mu\
Higgs Critical Exponents and Conformal Bootstrap in Four Dimensions
Oleg Antipin; Esben Mølgaard; Francesco Sannino
2015-05-11T23:59:59.000Z
We investigate relevant properties of composite operators emerging in nonsupersymmetric, four-dimensional gauge-Yukawa theories with interacting conformal fixed points within a precise framework. The theories investigated in this work are structurally similar to the standard model of particle interactions, but differ by developing perturbative interacting fixed points. We investigate the physical properties of the singlet and the adjoint composite operators quadratic in the Higgs field, and discover that the singlet anomalous dimension is substantially larger than the adjoint one. The numerical bootstrap results are then compared to precise four dimensional conformal field theoretical results. To accomplish this, it was necessary to calculate explicitly the crossing symmetry relations for the global symmetry group SU($N$)$\\times$SU($N$).
The Metastability Threshold for Modified Bootstrap Percolation in d Dimensions
Alexander E. Holroyd
2006-04-03T23:59:59.000Z
In the modified bootstrap percolation model, sites in the cube {1,...,L}^d are initially declared active independently with probability p. At subsequent steps, an inactive site becomes active if it has at least one active nearest neighbour in each of the d dimensions, while an active site remains active forever. We study the probability that the entire cube is eventually active. For all d>=2 we prove that as L\\to\\infty and p\\to 0 simultaneously, this probability converges to 1 if L=exp^{d-1} (lambda+epsilon)/p, and converges to 0 if L=exp^{d-1} (lambda-epsilon)/p, for any epsilon>0. Here exp^n denotes the n-th iterate of the exponential function, and the threshold lambda equals pi^2/6 for all d.
Strongly interacting confined quantum systems in one dimension
A. G. Volosniev; D. V. Fedorov; A. S. Jensen; M. Valiente; N. T. Zinner
2015-05-24T23:59:59.000Z
In one dimension, the study of magnetism dates back to the dawn of quantum mechanics when Bethe solved the famous Heisenberg model that describes quantum behaviour in magnetic systems. In the last decade, one-dimensional systems have become a forefront area of research driven by the realization of the Tonks-Girardeau gas using cold atomic gases. Here we prove that one-dimensional fermionic and bosonic systems with strong short-range interactions are solvable in arbitrary confining geometries by introducing a new energy-functional technique and obtaining the full spectrum of energies and eigenstates. As a first application, we calculate spatial correlations and show how both ferro- and anti-ferromagnetic states are present already for small system sizes that are prepared and studied in current experiments. Our work demonstrates the enormous potential for quantum manipulation of magnetic correlations at the microscopic scale.
Dirac equation in low dimensions: The factorization method
J. A. Sanchez-Monroy; C. J. Quimbay
2014-09-30T23:59:59.000Z
We present a general approach to solve the (1+1) and (2+1)-dimensional Dirac equation in the presence of static scalar, pseudoscalar and gauge potentials, for the case in which the potentials have the same functional form and thus the factorization method can be applied. We show that the presence of electric potentials in the Dirac equation leads to a two Klein-Gordon equations including an energy-dependent potential. We then generalize the factorization method for the case of energy-dependent Hamiltonians. Additionally, the shape invariance is generalized for a specific class of energy-dependent Hamiltonians. We also present a condition for the absence of the Klein's paradox (stability of the Dirac sea), showing how Dirac particles in low dimensions can be confined for a wide family of potentials.
Diesel lube oils; Fourth dimension of diesel particulate control
Springer, K.J. (Southwest Research Institute, San Antonio, TX (US))
1989-07-01T23:59:59.000Z
Particulate emission control, for the HD diesel engine, has previously been considered a three-dimensional problem involving: combustion of the fuel by the engine, fuel modification, and exhaust aftertreatment. The lube oil contribution may be considered a fourth dimension of the problem. Historically, the heavy-duty engine manufacturer has met emission standards for smoke (1968 to present), CO, HC, and NOx (1974 to present) and particulates (1988 to present) through changes in engine design. This paper used the allocation method to estimate the reduction in lube oil consumption needed to meet 1991 and 1994 U.S. particulate emission standards. This analysis places the contribution of lube oil as a source of exhaust particulates into prospective with the contributions from fuel sulfur and fuel combustion. An emissions control strategy to meet future regulations is offered in which reductions from fuel modification, combustion improvement, reduced lube oil consumption, and exhaust particulate trap-catalysts are all involved.
Cross product in N Dimensions - the doublewedge product
Carlo Andrea Gonano; Riccardo Enrico Zich
2014-07-21T23:59:59.000Z
The cross product frequently occurs in Physics and Engineering, since it has large applications in many contexts, e.g. for calculating angular momenta, torques, rotations, volumes etc. Though this mathematical operator is widely used, it is commonly expressed in a 3-D notation which gives rise to many paradoxes and difficulties. In fact, instead of other vector operators like scalar product, the cross product is defined just in 3-D space, it does not respect reflection rules and invokes the concept of "handedness". In this paper we are going to present an extension of cross product in an arbitrary number N of spatial Dimensions, different from the one adopted in the Exterior Algebra and explicitly designed for an easy calculus of moments.
Extra dimensions and neutrinoless double beta decay experiments
Gozdz, Marek; Kaminski, Wieslaw A.; Faessler, Amand [Theoretical Physics Department, Maria Curie-Sklodowska University, Lublin (Poland); Institute fuer Theoretische Physik, Universitaet Tuebingen, Auf der Morgenstelle 14, D-72076 Tuebingen (Germany)
2005-05-01T23:59:59.000Z
The neutrinoless double beta decay is one of the few phenomena, belonging to the nonstandard physics, which is extensively being sought for in experiments. In the present paper the link between the half-life of the neutrinoless double beta decay and theories with large extra dimensions is explored. The use of the sensitivities of currently planned 0{nu}2{beta} experiments: DAMA, CANDLES, COBRA, DCBA, CAMEO, GENIUS, GEM, MAJORANA, MOON, CUORE, EXO, and XMASS, gives the possibility for a nondirect 'experimental' verification of various extra dimensional scenarios. We discuss also the results of the Heidelberg-Moscow Collaboration. The calculations are based on the Majorana neutrino mass generation mechanism in the Arkani-Hamed-Dimopoulos-Dvali model.
Sparse matrix transform for fast projection to reduced dimension
Theiler, James P [Los Alamos National Laboratory; Cao, Guangzhi [GE HEALTHCARE; Bouman, Charles A [PURDUE UNIV
2010-01-01T23:59:59.000Z
We investigate three algorithms that use the sparse matrix transform (SMT) to produce variance-maximizing linear projections to a lower-dimensional space. The SMT expresses the projection as a sequence of Givens rotations and this enables computationally efficient implementation of the projection operator. The baseline algorithm uses the SMT to directly approximate the optimal solution that is given by principal components analysis (PCA). A variant of the baseline begins with a standard SMT solution, but prunes the sequence of Givens rotations to only include those that contribute to the variance maximization. Finally, a simpler and faster third algorithm is introduced; this also estimates the projection operator with a sequence of Givens rotations, but in this case, the rotations are chosen to optimize a criterion that more directly expresses the dimension reduction criterion.
Black holes in extra dimensions can decay on the bulk
A. K. Chaudhuri
2003-01-08T23:59:59.000Z
In the extra dimensional theories, with TeV scale Plank constant, black holes may be produced in the Large Hadron Collider experiments. We have argued that in the d-dimensional black hole, the intrinsically 4-dimensional brane fields do not see the same geometry at the horizon, as in a 4-dimensional space-time. Kaluza-Klein modes invades the brane and surroundings and the brane fields can be considered as a thermal system at the temperature of the black hole. From energy and entropy consideration, we show that whether or not a six-dimensional black hole will decay by emitting Kaluza-Klein modes or the standard model particles, will depend on the length scale of the extra dimensions as well as on the mass of the black hole. For higher dimensional black holes, Kaluza-Klein modes will dominate the decay.
The Need of Dark Energy for Dynamical Compactification of Extra Dimensions on the Brane
Cuadros-Melgar, B; Cuadros-Melgar, Bertha; Papantonopoulos, Eleftherios
2005-01-01T23:59:59.000Z
We consider a six-dimensional braneworld model and we study the cosmological evolution of a (4+1) brane-universe. Introducing matter on the brane we show that the scale factor of the physical three-dimensional brane-universe is related to the scale factor of the fourth dimension on the brane, and the suppression of the extra dimension compared to the three dimensions requires the presence of dark energy.
The Need of Dark Energy for Dynamical Compactification of Extra Dimensions on the Brane
Bertha Cuadros-Melgar; Eleftherios Papantonopoulos
2005-08-31T23:59:59.000Z
We consider a six-dimensional braneworld model and we study the cosmological evolution of a (4+1) brane-universe. Introducing matter on the brane we show that the scale factor of the physical three-dimensional brane-universe is related to the scale factor of the fourth dimension on the brane, and the suppression of the extra dimension compared to the three dimensions requires the presence of dark energy.
Non-linear scaling of performance appraisal dimensions: application of the ProMES methodology
Hedley, Amie Lynn
1990-01-01T23:59:59.000Z
of an employee to the organization. For example, one dimension of performance might be the ability of an employee to effectively communicate with co-workers. In order to determine what these performance dimensions might be, interviews were conducted. 22... overall composite, the raw scores were converted to z-scores. In order to do this, the mean and standard deviation were computed for each performance dimension. These calculations were done across the subjects in all three groups. An employee's z...
Packing Dimension Profiles and Levy Processes D. Khoshnevisan, R.L. Schilling and Y. Xiao
Khoshnevisan, Davar
that computes the Hausdorff dimension dimH X(F) of X(F), see [13] and its extensive bibliography. Let dimP denote the packing dimension. The main goal of the present paper is to evaluate dimP X(F) in terms study the packing dimension dimP X(F). Let us point out two noteworthy cases where dimP X(F) has been
Non-linear scaling of performance appraisal dimensions: application of the ProMES methodology
Hedley, Amie Lynn
1990-01-01T23:59:59.000Z
of an employee to the organization. For example, one dimension of performance might be the ability of an employee to effectively communicate with co-workers. In order to determine what these performance dimensions might be, interviews were conducted. 22... overall composite, the raw scores were converted to z-scores. In order to do this, the mean and standard deviation were computed for each performance dimension. These calculations were done across the subjects in all three groups. An employee's z...
ON THE DIMENSION OF THE SET OF RIM PERTURBATIONS FOR OPTIMAL PARTITION INVARIANCE
Greenberg, Harvey J.
that if the dimension of the primal optimality region, dim(P ), is zero, this means it is an extreme point.
HOW BEHAVE THE TYPICAL Lq-DIMENSIONS OF MEASURES? FREDERIC BAYART
Boyer, Edmond
. The Hausdorff and the packing dimension of E are denoted respectively by dimH(E) and dimP(E). Also, for a subset
The inverse conductivity problem with power densities in dimension n2
François Monard, Guillaume Bal
2012-06-19T23:59:59.000Z
Jun 19, 2012 ... The inverse conductivity problem with power densities in dimension n ? 2. François Monard Guillaume Bal. Dept. of Applied Physics and ...
Extra Dimensions: 3D and Time in PDF Documentation
Graf, Norman A.; /SLAC
2011-11-10T23:59:59.000Z
High energy physics is replete with multi-dimensional information which is often poorly represented by the two dimensions of presentation slides and print media. Past efforts to disseminate such information to a wider audience have failed for a number of reasons, including a lack of standards which are easy to implement and have broad support. Adobe's Portable Document Format (PDF) has in recent years become the de facto standard for secure, dependable electronic information exchange. It has done so by creating an open format, providing support for multiple platforms and being reliable and extensible. By providing support for the ECMA standard Universal 3D (U3D) file format in its free Adobe Reader software, Adobe has made it easy to distribute and interact with 3D content. By providing support for scripting and animation, temporal data can also be easily distributed to a wide audience. In this talk, we present examples of HEP applications which take advantage of this functionality. We demonstrate how 3D detector elements can be documented, using either CAD drawings or other sources such as GEANT visualizations as input. Using this technique, higher dimensional data, such as LEGO plots or time-dependent information can be included in PDF files. In principle, a complete event display, with full interactivity, can be incorporated into a PDF file. This would allow the end user not only to customize the view and representation of the data, but to access the underlying data itself.
Dimensions of Usability: Cougaar, Aglets and Adaptive Agent Architecture (AAA)
Haack, Jereme N.; Cowell, Andrew J.; Gorton, Ian
2004-06-20T23:59:59.000Z
Research and development organizations are constantly evaluating new technologies in order to implement the next generation of advanced applications. At Pacific Northwest National Laboratory, agent technologies are perceived as an approach that can provide a competitive advantage in the construction of highly sophisticated software systems in a range of application areas. An important factor in selecting a successful agent architecture is the level of support it provides the developer in respect to developer support, examples of use, integration into current workflow and community support. Without such assistance, the developer must invest more effort into learning instead of applying the technology. Like many other applied research organizations, our staff are not dedicated to a single project and must acquire new skills as required, underlining the importance of being able to quickly become proficient. A project was instigated to evaluate three candidate agent toolkits across the dimensions of support they provide. This paper reports on the outcomes of this evaluation and provides insights into the agent technologies evaluated.
Global Fits of the Minimal Universal Extra Dimensions Scenario
Bertone, Gianfranco; /Zurich U. /Paris, Inst. Astrophys.; Kong, Kyoungchul; /SLAC /Kansas U.; de Austri, Roberto Ruiz; /Valencia U., IFIC; Trotta, Roberto; /Imperial Coll., London
2012-06-22T23:59:59.000Z
In theories with Universal Extra-Dimensions (UED), the {gamma}{sub 1} particle, first excited state of the hypercharge gauge boson, provides an excellent Dark Matter (DM) candidate. Here we use a modified version of the SuperBayeS code to perform a Bayesian analysis of the minimal UED scenario, in order to assess its detectability at accelerators and with DM experiments. We derive in particular the most probable range of mass and scattering cross sections off nucleons, keeping into account cosmological and electroweak precision constraints. The consequences for the detectability of the {gamma}{sub 1} with direct and indirect experiments are dramatic. The spin-independent cross section probability distribution peaks at {approx} 10{sup -11} pb, i.e. below the sensitivity of ton-scale experiments. The spin-dependent cross-section drives the predicted neutrino flux from the center of the Sun below the reach of present and upcoming experiments. The only strategy that remains open appears to be direct detection with ton-scale experiments sensitive to spin-dependent cross-sections. On the other hand, the LHC with 1 fb{sup -1} of data should be able to probe the current best-fit UED parameters.
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.
The sharp threshold for bootstrap percolation in all dimensions
József Balogh; Béla Bollobás; Hugo Duminil-Copin; Robert Morris
2011-02-24T23:59:59.000Z
In r-neighbour bootstrap percolation on a graph G, a (typically random) set A of initially 'infected' vertices spreads by infecting (at each time step) vertices with at least r already-infected neighbours. This process may be viewed as a monotone version of the Glauber dynamics of the Ising model, and has been extensively studied on the d-dimensional grid $[n]^d$. The elements of the set A are usually chosen independently, with some density p, and the main question is to determine $p_c([n]^d,r)$, the density at which percolation (infection of the entire vertex set) becomes likely. In this paper we prove, for every pair $d \\ge r \\ge 2$, that there is a constant L(d,r) such that $p_c([n]^d,r) = [(L(d,r) + o(1)) / log_(r-1) (n)]^{d-r+1}$ as $n \\to \\infty$, where $log_r$ denotes an r-times iterated logarithm. We thus prove the existence of a sharp threshold for percolation in any (fixed) number of dimensions. Moreover, we determine L(d,r) for every pair (d,r).
Gauge symmetries decrease the number of Dp-brane dimensions
Nikolic, B.; Sazdovic, B. [Institute of Physics, 11001 Belgrade, P.O. Box 57 (Serbia and Montenegro)
2006-08-15T23:59:59.000Z
It is known that the presence of the antisymmetric background field B{sub {mu}}{sub {nu}} leads to the noncommutativity of the Dp-brane manifold. The addition of the linear dilaton field in the form {phi}(x)={phi}{sub 0}+a{sub {mu}}x{sup {mu}} causes the appearance of the commutative Dp-brane coordinate x=a{sub {mu}}x{sup {mu}}. In the present article we show that for some particular choices of the background fields, a{sup 2}{identical_to}G{sup {mu}}{sup {nu}}a{sub {mu}}a{sub {nu}}=0 and a-tilde{sup 2}{identical_to}[(G-4BG{sup -1}B){sup -1}]{sup {mu}}{sup {nu}}a{sub {mu}}a{sub {nu}}=0, the local gauge symmetries appear in the theory. They turn some Neuman boundary conditions into the Dirichlet ones, and consequently decrease the number of the Dp-brane dimensions.
The Compactification Problems of Additional Dimensions in Multidimensional Cosmological Theories
Tamerlan Saidov
2011-11-30T23:59:59.000Z
Multidimensionality of our Universe is one of the most intriguing assumption in modern physics. It follows naturally from theories unifying different fundamental interactions with gravity, e.g. M/string theory. The idea has received a great deal of renewed attention over the last few years. However, it also brings a row of additional questions. According to observations the internal space should be static or nearly static at least from the time of primordial nucleosynthesis, otherwise the fundamental physical constants would vary. This means that at the present evolutionary stage of the Universe there are two possibilities: slow variation or compactification of internal space scale parameters. In many recent studies the problem of extra dimensions stabilization was studied for so-called ADD. Under these approaches a massive scalar fields (gravitons or radions) of external space-time can be presented as conformal excitations. In above mentioned works it was assumed that multidimensional action to be linear with respect to curvature. Although as follows from string theory, the gravity action needs to be extended to nonlinear one. In order to investigate effects of nonlinearity, in this Thesis a multidimensional Lagrangian will be studied, having the form L = f(R), where f(R) is an arbitrary smooth function of the scalar curvature.
DIMENSIONS: Why do we need a new Data Handling architecture for Sensor Networks?
Ganesan, Deepak
DIMENSIONS: Why do we need a new Data Handling architecture for Sensor Networks? Deepak Ganesan incorporate their ex- treme resource constraints - energy, storage and processing - and spatio-temporal interpretation of the physical world in the design, cost model, and metrics of evaluation. We describe DIMENSIONS
On ascertaining inductively the dimension of the joint kernel of certain commuting linear operators
Shen, Zuowei
On ascertaining inductively the dimension of the joint kernel of certain commuting linear operators), and a collection f`xgx2X of commuting linear maps on some linear space, the family of linear operators whose joint DMS-9000053, DMS-9102857. i #12;proposed running head: dimension of joint kernels Proofs should
Texas at Austin. University of
Fractal dimension and unscreened angles measured for radial viscous fingering Olivier Praud fractal patterns formed by the injection of air into oil in a thin 0.127 mm layer contained between two reaches r/b=900, are far larger than in past experiments. The fractal dimension D0 of the pattern
Lower scaling dimensions of quarks and gluons and new energy scales
F. Palumbo
1996-05-08T23:59:59.000Z
We consider the possibility that quarks and gluons, due to confinement, have lower scaling dimensions. In such a case there appear naturally new energy scales below which the standard theory is recovered. Arguments are given whereby for dimension $1/2$ of the quarks the theory is unitary also above these energy scales.
Comment on the shape of Hydrogen equation in spaces of arbitrary dimension
M. Ya. Amusia
2015-02-20T23:59:59.000Z
We note that presenting Hydrogen atom Schrodinger equation in the case of arbitrary dimensions require simultaneous modification of the Coulomb potential that only in three dimensions has the form Z/r . This was not done in a number of relatively recent papers [1-5]. Therefore some results obtained there seem to be doubtful. Some required considerations in the area are mentioned.
A numerical study on the dimension of an extremely inhomogeneous matter distribution
Cecilia B. M. H. Chirenti
2005-08-10T23:59:59.000Z
We have developed an algorithm that numericaly computes the dimension of an extremely inhomogeous matter distribution, given by a discrete hierarchical metric. With our results it is possible to analise how the dimension of the matter density tends to d = 3, as we consider larger samples.
Packing Dimension and Cartesian Products Christopher J. Bishop1 Yuval Peres2
Bishop, Christopher
that (dimH (A B) dimH(B)) ~ dimP(A) ; (1) where "dimP " denotes packing dimension (see) showed that dimP(E F ) ~ dimH(E) + dimP(F ) : (3) Hu the "* *regular- ization" of this index the lower packing dimension, denoted dim_P, although it * *is
A wideband fast multipole method for the Helmholtz equation in three dimensions
Martinsson, Gunnar
A wideband fast multipole method for the Helmholtz equation in three dimensions Hongwei Cheng of the Fast Multipole Method for the Helmholtz equation in three dimensions. It uni- fies previously existing Inc. All rights reserved. MSC: 65R99; 78A45 Keywords: Helmholtz equation; Fast multipole method
A NEW FAST-MULTIPOLE ACCELERATED POISSON SOLVER IN TWO DIMENSIONS
Greengard, Leslie
A NEW FAST-MULTIPOLE ACCELERATED POISSON SOLVER IN TWO DIMENSIONS FRANK ETHRIDGE AND LESLIEÂ760 Abstract. We present an adaptive fast multipole method for solving the Poisson equation in two dimensions for highly nonuniform grids. Key words. fast multipole method, Poisson equation, adaptive refinement, fast
Change of order for regular chains in positive dimension Xavier Dahan , Xin Jin
Moreno Maza, Marc
in dimension zero; ·Newton-Hensel lifting. Basic setup Let V be an irreducible variety of dimension r, defined, . . . , yr) kr , Ts(y, Z1, . . . , Zs) ... T1(y, Z1) Specialize and lift paradigm: intermediate computations. lift v in T; [dim. 1] 3. specialize w at a random value. [dim. 0] Algorithm Input. ·A regular chain Tin
The wavelet dimension function for real dilations and dilations admitting non-MSF wavelets
Speegle, Darrin
The wavelet dimension function for real dilations and dilations admitting non-MSF wavelets Marcin Bownik and Darrin Speegle Abstract. The wavelet dimension function for arbitrary real dilations is defined and used to address several questions involving the existence of MRA wavelets and well
Almost global existence for nonlinear wave equations in an exterior domain in two space dimensions
Hideo Kubo
2012-05-26T23:59:59.000Z
In this paper we deal with the exterior problem for a system of nonlinear wave equations in two space dimensions, assuming that the initial data is small and smooth. We establish the same type of lower bound of the lifespan for the problem as that for the Cauchy problem, despite of the weak decay property of the solution in two space dimensions.
WILD ALGEBRAS HAVE ONE-POINT EXTENSIONS OF REPRESENTATION DIMENSION AT LEAST FOUR
Oppermann, Steffen
WILD ALGEBRAS HAVE ONE-POINT EXTENSIONS OF REPRESENTATION DIMENSION AT LEAST FOUR STEFFEN OPPERMANN Abstract. We show that any wild algebra has a one-point exten- sion of representation dimension at least between tame and wild representation type is another way of saying "how infinite" the representation
PHYSICAL REVIEW B 86, 184504 (2012) Topological excitonic superfluids in three dimensions
Gilbert, Matthew
PHYSICAL REVIEW B 86, 184504 (2012) Topological excitonic superfluids in three dimensions Youngseok exciton condensates within time-reversal invariant topological insulators in three spatial dimensions two-dimensional (2D) Dirac surface states separated by an insulating spacer.22Â26 Yet the existence
Lyapunov instability of rigid diatomic molecules in three dimensions: A simpler method Seungho Choe1
Lee, EokKyun
Lyapunov instability of rigid diatomic molecules in three dimensions: A simpler method Seungho Choe 2007 We present a method to calculate Lyapunov exponents of rigid diatomic molecules in three dimensions 12N-dimensional phase space . The spectra of Lyapunov exponents are obtained for 32 rigid diatomic
THE LYAPUNOV AND DIMENSION SPECTRA OF EQUILIBRIUM MEASURES FOR CONFORMAL EXPANDING MAPS.
THE LYAPUNOV AND DIMENSION SPECTRA OF EQUILIBRIUM MEASURES FOR CONFORMAL EXPANDING MAPS. HOWARD the dimension spectrum for equilibrium measures and the Lyapunov spectrum for conformal repellers. We explicitly compute the Lyapunov spectrum and show that it is a delta function. We observe that while the Lyapunov
Process Dimension of Classical and Non-Commutative Processes Wolfgang Lohr1,2
#12;Process Dimension of Classical and Non-Commutative Processes Wolfgang L¨ohr1,2 Arleta Szkola1-commutative generalisation, which we call NC-OOMs. A natural characteristic of a stochastic process in the context of classical OOM theory is the process dimension. We investigate its properties within the more general
Efficient Scheme of Experimental Quantifying non-Markovianity in High-Dimension Systems
S. -J. Dong; B. -H. Liu; Y. -N. Sun; Y. -J. Han; G. -C. Guo; Lixin He
2015-01-29T23:59:59.000Z
The non-Markovianity is a prominent concept of the dynamics of the open quantum systems, which is of fundamental importance in quantum mechanics and quantum information. Despite of lots of efforts, the experimentally measuring of non-Markovianity of an open system is still limited to very small systems. Presently, it is still impossible to experimentally quantify the non-Markovianity of high dimension systems with the widely used Breuer-Laine-Piilo (BLP) trace distance measure. In this paper, we propose a method, combining experimental measurements and numerical calculations, that allow quantifying the non-Markovianity of a $N$ dimension system only scaled as $N^2$, successfully avoid the exponential scaling with the dimension of the open system in the current method. After the benchmark with a two-dimension open system, we demonstrate the method in quantifying the non-Markovanity of a high dimension open quantum random walk system.
The Local Dimension: a method to quantify the Cosmic Web
Prakash Sarkar; Somnath Bharadwaj
2008-12-09T23:59:59.000Z
It is now well accepted that the galaxies are distributed in filaments, sheets and clusters all of which form an interconnected network known as the Cosmic Web. It is a big challenge to quantify the shapes of the interconnected structural elements that form this network. Tools like the Minkowski functionals which use global properties, though well suited for an isolated object like a single sheet or filament, are not suited for an interconnected network of such objects. We consider the Local Dimension $D$, defined through $N(R)=A R^D$, where $N(R)$ is the galaxy number count within a sphere of comoving radius $R$ centered on a particular galaxy, as a tool to locally quantify the shape in the neigbourhood of different galaxies along the Cosmic Web. We expect $D \\sim 1,2$ and 3 for a galaxy located in a filament, sheet and cluster respectively. Using LCDM N-body simulations we find that it is possible to determine $D$ through a power law fit to $N(R)$ across the length-scales 2 to $10 {\\rm Mpc}$ for $\\sim 33 %$ of the galaxies. We have visually identified the filaments and sheets corresponding to many of the galaxies with $D \\sim 1$ and 2 respectively. In several other situations the structure responsible for the $D$ value could not be visually identified, either due to its being tenuous or due to other dominating structures in the vicinity. We also show that the global distribution of the $D$ values can be used to visualize and interpret how the different structural elements are woven into the Cosmic Web.
Human dimensions in cyber operations research and development priorities.
Forsythe, James Chris; Silva, Austin Ray; Stevens-Adams, Susan Marie; Bradshaw, Jeffrey [Institute for Human and Machine Cognition
2012-11-01T23:59:59.000Z
Within cyber security, the human element represents one of the greatest untapped opportunities for increasing the effectiveness of network defenses. However, there has been little research to understand the human dimension in cyber operations. To better understand the needs and priorities for research and development to address these issues, a workshop was conducted August 28-29, 2012 in Washington DC. A synthesis was developed that captured the key issues and associated research questions. Research and development needs were identified that fell into three parallel paths: (1) human factors analysis and scientific studies to establish foundational knowledge concerning factors underlying the performance of cyber defenders; (2) development of models that capture key processes that mediate interactions between defenders, users, adversaries and the public; and (3) development of a multi-purpose test environment for conducting controlled experiments that enables systems and human performance measurement. These research and development investments would transform cyber operations from an art to a science, enabling systems solutions to be engineered to address a range of situations. Organizations would be able to move beyond the current state where key decisions (e.g. personnel assignment) are made on a largely ad hoc basis to a state in which there exist institutionalized processes for assuring the right people are doing the right jobs in the right way. These developments lay the groundwork for emergence of a professional class of cyber defenders with defined roles and career progressions, with higher levels of personnel commitment and retention. Finally, the operational impact would be evident in improved performance, accompanied by a shift to a more proactive response in which defenders have the capacity to exert greater control over the cyber battlespace.
Low dimension structures and devices for new generation photonic technology
Zhang, D. H.; Tang, D. Y.; Chen, T. P. [School of Electrical and Electronic Engineering, Nanyang Technological University, 679798 (Singapore); Mei, T. [Institute of Optoelectronic Materials and Technology, South China Normal University, Guangzhou 510631 (China); Yuan, X. C. [Institute of Modern Optics, Nankai University, Tianjin 300071 (China)
2014-05-15T23:59:59.000Z
Low dimensional structures and devices are the key technological building blocks for new generation of electronic and photonic technology. Such structures and devices show novel properties and can be integrated into systems for wide applications in many areas, including medical, biological and military and advancement of science. In this invited talk, I will present the main results achieved in our competitive research program which aims to explore the application of the mesoscopic structures in light source, manipulation and imaging and integrate them into advanced systems. In the light source aspect, we have for the first time developed graphene mode-locked lasers which are in the process of commercialization. Nanocrystal Si embedded in dielectrics was formed by ion implantation and subsequent annealing. Si light emitting devices with external quantum efficiency of about 2.9×10{sup ?3}% for visible emission were demonstrated at room temperature and the color of emitted light can be tuned electrically from violet to white by varying the injected current. In light manipulation, loss compensation of surface plasmon polaritons (SPPs) using quantum well (QW) gain media was studied theoretically and demonstrated experimentally. The SPP propagation length was effectively elongated several times through electrical pumping. One and two microring resonators based on silicon on insulator and III-V semiconductors technologies have been successfully fabricated and they can be used as filter and switch in the photonic circuit. In imaging, both SPP and low dimension structures are investigated and resolution far beyond diffraction limit in visible range has been realized. The integration of the components in the three aspects into complicated systems is on the way.
Fractal Dimensions of a Weakly Clustered Distribution and the Scale of Homogeneity
J. S. Bagla; Jaswant Yadav; T. R. Seshadri
2008-08-04T23:59:59.000Z
Homogeneity and isotropy of the universe at sufficiently large scales is a fundamental premise on which modern cosmology is based. Fractal dimensions of matter distribution is a parameter that can be used to test the hypothesis of homogeneity. In this method, galaxies are used as tracers of the distribution of matter and samples derived from various galaxy redshift surveys have been used to determine the scale of homogeneity in the Universe. Ideally, for homogeneity, the distribution should be a mono-fractal with the fractal dimension equal to the ambient dimension. While this ideal definition is true for infinitely large point sets, this may not be realised as in practice, we have only a finite point set. The correct benchmark for realistic data sets is a homogeneous distribution of a finite number of points and this should be used in place of the mathematically defined fractal dimension for infinite number of points (D) as a requirement for approach towards homogeneity. We derive the expected fractal dimension for a homogeneous distribution of a finite number of points. We show that for sufficiently large data sets the expected fractal dimension approaches D in absence of clustering. It is also important to take the weak, but non-zero amplitude of clustering at very large scales into account. In this paper we also compute the expected fractal dimension for a finite point set that is weakly clustered. Clustering introduces departures in the Fractal dimensions from D and in most situations the departures are small if the amplitude of clustering is small. Features in the two point correlation function, like those introduced by Baryon Acoustic Oscillations (BAO) can lead to non-trivial variations in the Fractal dimensions where the amplitude of clustering and deviations from D are no longer related in a monotonic manner.
Chakhlov, V.L.; Kashovskii, V.V.; Pushin, V.S.
1985-09-01T23:59:59.000Z
The authors discuss the results of refinement of the dynamics of particles of a beam extracted from a betatron, a refinement which has made it possible to select the main dimensions of the accelerating chamber. Expressions are obtained which make it possible to determine the chamber dimensions and the profile of the extraction window from the distribution of the magnetic field of the betatron. It is shown that proper selection of the dimensions will increase the dose rate at the exit from the magnetic core of the accelerator.
Extending the Standard Model Effective Field Theory with the Complete Set of Dimension-7 Operators
Landon Lehman
2014-12-26T23:59:59.000Z
We present a complete list of the independent dimension-7 operators that are constructed using the Standard Model degrees of freedom and are invariant under the Standard Model gauge group. This list contains only 20 independent operators; far fewer than the 63 operators available at dimension 6. All of these dimension-7 operators contain fermions and violate lepton number, and 7 of the 20 violate baryon number as well. This result extends the Standard Model Effective Field Theory (SMEFT) and allows a more detailed exploration of the structure and properties of possible deformations from the Standard Model Lagrangian.
Boom and Bust Inflation: A Graceful Exit via Compact Extra Dimensions
Brown, Adam R. [Physics Department, Columbia University, New York, New York 10027 (United States)
2008-11-28T23:59:59.000Z
A model of inflation is proposed in which compact extra dimensions allow a graceful exit without recourse to flat potentials or super-Planckian field values. Though bubbles of true vacuum are too sparse to uniformly reheat the Universe by colliding with each other, a compact dimension enables a single bubble to uniformly reheat by colliding with itself. This mechanism, which generates an approximately scale invariant perturbation spectrum, requires that inflation be driven by a bulk field, that vacuum decay be slow, and that the extra dimension be at least a hundred times larger than the false vacuum Hubble length.
Fixed Points Structure & Effective Fractional Dimension for O(N) Models with Long-Range Interactions
Nicolo Defenu; Andrea Trombettoni; Alessandro Codello
2014-11-25T23:59:59.000Z
We study O(N) models with power-law interactions by using functional renormalization group methods: we show that both in Local Potential Approximation (LPA) and in LPA' their critical exponents can be computed from the ones of the corresponding short-range O(N) models at an effective fractional dimension. In LPA such effective dimension is given by $D_{eff}=2d/\\sigma$, where d is the spatial dimension and $d+\\sigma$ is the exponent of the power-law decay of the interactions. In LPA' the prediction by Sak [Phys. Rev. B 8, 1 (1973)] for the critical exponent $\\eta$ is retrieved and an effective fractional dimension $D_{eff}'$ is obtained. Using these results we determine the existence of multicritical universality classes of long-range O(N) models and we present analytical predictions for the critical exponent $\
Recurrence, dimension and entropy Ai-hua FAN De-jun FENG Jun WU
Feng, De-Jun
are then defined on . We shall talk about_the Hausdorff dimensio* *n dimH , the packing dimension dimP dimH E (ff) = dimP E (ff) = _____ max h~ logm ~2F
A LOCAL DIMENSION TEST FOR NUMERICALLY APPROXIMATED POINTS ON ALGEBRAIC SETS
Sommese, Andrew J.
, denoted here as dimp(V ). This article presents a rigorous numerical local dimension test. The test (and computing the mult* *i- plicity if it is); 2.computing dimp(V ) for nonisolated
A LOCAL DIMENSION TEST FOR NUMERICALLY APPROXIMATED POINTS ON ALGEBRAIC SETS
Sommese, Andrew J.
, denoted here as dimp(V ). This article presents a rigorous numerical local dimension test. The test, which- plicity if it is); 2. computing dimp(V ) for nonisolated points p; 3. finding all irreducible components
A LOCAL DIMENSION TEST FOR NUMERICALLY APPROXIMATED POINTS ON ALGEBRAIC SETS
Sommese, Andrew J.
containing p, denoted here as dimp (V ). This article presents a rigorous numerical local dimension test the multiÂ plicity if it is); 2. computing dimp (V ) for nonisolated points p; 3. finding all irreducible
An Examination of Magical Beliefs as Predictors of Obsessive-Compulsive Symptom Dimensions
Spears, Lauren
2014-08-31T23:59:59.000Z
study improved on methodological limitations of previous studies and used the Dimensional Obsessive-Compulsive Scale (DOCS) to conceptualize OCD as a dimensional construct. Relationships between magical belief constructs and four OCD symptom dimensions...
Einstein-Born-Infeld on Taub-NUT Spacetime in 2k+2 Dimensions
A. Khodam-Mohammadi
2009-05-26T23:59:59.000Z
We wish to construct solutions of Taub-NUT spacetime in Einstein-Born-Infeld gravity in even dimensions. Since Born-Infeld theory is a nonlinear electrodynamics theory, in leads to nonlinear differential equations. However a proper analytical solution was not obtain, we try to solve it numerically (by the Runge-Kotta method) with initial conditions coinciding with those of our previous work in Einstein-Maxwell gravity. We solve equations for 4, 6 and 8 dimensions and do data fitting by the least-squares method. For N=l=b=1, the metric turns to the NUT solution only in 8 dimensions, but in 4 and 6 dimensions the spacetime does not have any Nut solution.
Title: Multimedia Kaleidoscope: New dimensions for the organization of social multimedia
Title: Multimedia Kaleidoscope: New dimensions for the organization of social multimedia Responsible lab: Delft Multimedia Information Retrieval Lab Martha impression of a possible design for a multimedia Kaleidoscope Description
Title: Multimedia Kaleidoscope: New dimensions for the organization of social multimedia
Title: Multimedia Kaleidoscope: New dimensions for the organization of social multimedia Description: A multimedia kaleidoscope is a dynamic collection.g., blogs and Twitter content) and multimedia (e.g., Flickr and other image
Rajesh Maingi adds a new strategic dimension to fusion and plasma...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Rajesh Maingi adds a new strategic dimension to fusion and plasma physics research By John Greenwald March 14, 2013 Tweet Widget Google Plus One Share on Facebook Rajesh Maingi...
HAUSDORFF DIMENSION, ANALYTIC SETS AND TRANSCENDENCE G. A. EDGAR AND CHRIS MILLER
Edgar, Gerald
HAUSDORFF DIMENSION, ANALYTIC SETS AND TRANSCENDENCE G. A. EDGAR AND CHRIS MILLER Abstract. Every, is the infimum of all s # 0 such that H s (A) = 0. (See any of Edgar [5], Falconer [7], Mattila [9] or [11
A New Dimension in Access Control: Studying Maintenance Engineering across Organizational
A New Dimension in Access Control: Studying Maintenance Engineering across Organizational Inter-organizational cooperation has specific requirements for access control. The paper presents be extended to realize additional mechanisms for access control with little efforts. Keywords inter-organizational
More on critical collapse of axion-dilaton system in dimension four
Álvarez-Gaumé, Luis [Theory Group, Physics Department, CERN, CH-1211, Geneva 23 (Switzerland); Hatefi, Ehsan, E-mail: Luis.Alvarez-Gaume@cern.ch, E-mail: ehsan.hatefi@cern.ch [International Centre for Theoretical Physics, Strada Costiera 11, Trieste (Italy)
2013-10-01T23:59:59.000Z
We complete our previous study of critical gravitational collapse in the axion-dilaton system by analysing the hyperbolic and parabolic ansaetze. As could be expected, the corresponding Choptuik exponents in four-dimensions differ from the elliptic case.
Search for Signatures of Extra Dimensions in the Diphoton Mass Spectrum at the Large Hadron Collider
Bauer, Gerry P.
A search for signatures of extra spatial dimensions in the diphoton invariant-mass spectrum has been performed with the CMS detector at the LHC. No excess of events above the standard model expectation is observed using a ...
On the Dimensioning of Cellular OFDMA Networks Jean-Marc Kelifa
Boyer, Edmond
On the Dimensioning of Cellular OFDMA Networks Jean-Marc Kelifa , Marceau Coupechoux,b , Philippe.kelif@orange-ftgroup.com (Jean-Marc Kelif), coupecho@enst.fr (Marceau Coupechoux), godlewsk@enst.fr (Philippe Godlewski) Preprint
On the Fractal Dimension of Isosurfaces Marc Khoury and Rephael Wenger
Wenger, Rephael
On the Fractal Dimension of Isosurfaces Marc Khoury and Rephael Wenger 2 2.2 2.4 2.6 2.8 3 0 50 100 150 200 250 1 10 100 1000 10000 0 50 100 150 200 250 Fractal dimension Topological Noise (Number of Components) Isovalue 60 Isovalue 68 Isovalue 72 Fig. 1: Visible male data set (www.stereofx.org): Fractal box
Fractal dimension of the topological charge density distribution in SU(2) lattice gluodynamics
P. V. Buividovich; T. Kalaydzhyan; M. I. Polikarpov
2012-10-21T23:59:59.000Z
We study the effect of cooling on the spatial distribution of the topological charge density in quenched SU(2) lattice gauge theory with overlap fermions. We show that as the gauge field configurations are cooled, the Hausdorff dimension of regions where the topological charge is localized gradually changes from d = 2..3 towards the total space dimension. Therefore, the cooling procedure destroys some of the essential properties of the topological charge distribution.
POWER-LAW BOUNDS ON TRANSFER MATRICES AND QUANTUM DYNAMICS IN ONE DIMENSION
the proof of [20] that + #21; 1 d dimP (#22; ) (7) (with d #21; 1 in the case of l 2 (Z d ) and d = 1 , and dimH (#22;); dimP (#22;) denote the (upper) Hausdor#11; and packing dimensions of the measure #22 "!0 log #22;([E "; E + "]) log " ; E 2 supp #22;: For the packing dimension, we have dimP (#22;) = #22
Kitchen layout and dimensions for the ambulatory and wheelchair-bound elderly
Resendiz, Anita Janice
1985-01-01T23:59:59.000Z
KITCHEN LAYOUT AND DIMENSIONS FOR THE Al&ULATORY AND WHEELCHAIR-BOUND ELDERLY A Thesis ANITA JANICE RESENDIZ Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE August ' 9BS Major Subject: Industrial Engineering KITCHEN LAYOUT AND DIMENSIONS FOR THE AMBULATORY AND WHEELCHAIR-BOUND ELDERLY A Thesis by ANITA JANICE RESENDIZ Approved as to style and content by: R. D. uchings n (Chairman) G. Bayliss...
Rotating charged hairy black hole in (2+1) dimensions and particle acceleration
J. Sadeghi; B. Pourhassan; H. Farahani
2013-10-26T23:59:59.000Z
In this paper we construct rotating charged hairy black hole in (2+1) dimensions for infinitesimal black hole charge and rotation parameters. Then we consider this black hole as particle accelerator and calculate the center-of-mass energy of two colliding test particles near the rotating charged hairy black hole in (2+1) dimensions. As we expected, the center-of-mass energy has infinite value.
Entanglement Entropy of Gapped Phases and Topological Order in Three dimensions
Tarun Grover; Ari M. Turner; Ashvin Vishwanath
2011-08-19T23:59:59.000Z
We discuss entanglement entropy of gapped ground states in different dimensions, obtained on partitioning space into two regions. For trivial phases without topological order, we argue that the entanglement entropy may be obtained by integrating an `entropy density' over the partition boundary that admits a gradient expansion in the curvature of the boundary. This constrains the expansion of entanglement entropy as a function of system size, and points to an even-odd dependence on dimensionality. For example, in contrast to the familiar result in two dimensions, a size independent constant contribution to the entanglement entropy can appear for trivial phases in any odd spatial dimension. We then discuss phases with topological entanglement entropy (TEE) that cannot be obtained by adding local contributions. We find that in three dimensions there is just one type of TEE, as in two dimensions, that depends linearly on the number of connected components of the boundary (the `zeroth Betti number'). In D > 3 dimensions, new types of TEE appear which depend on the higher Betti numbers of the boundary manifold. We construct generalized toric code models that exhibit these TEEs and discuss ways to extract TEE in D >=3.
DIMENSION AS A KEY TO THE NEUTRINO MECHANISM OF CORE-COLLAPSE SUPERNOVA EXPLOSIONS
Nordhaus, J.; Burrows, A. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Almgren, A.; Bell, J., E-mail: nordhaus@astro.princeton.ed, E-mail: burrows@astro.princeton.ed, E-mail: ASAlmgren@lbl.go, E-mail: JBBell@lbl.go [Computational Research Division, Lawrence Berkeley National Lab, Berkeley, CA 94720 (United States)
2010-09-01T23:59:59.000Z
We explore the dependence on spatial dimension of the viability of the neutrino heating mechanism of core-collapse supernova explosions. We find that the tendency to explode is a monotonically increasing function of dimension, with three dimensions (3D) requiring {approx}40%-50% lower driving neutrino luminosity than one dimension and {approx}15%-25% lower driving neutrino luminosity than two dimensions (2D). Moreover, we find that the delay to explosion for a given neutrino luminosity is always shorter in 3D than 2D, sometimes by many hundreds of milliseconds. The magnitude of this dimensional effect is much larger than the purported magnitude of a variety of other effects, such as nuclear burning, inelastic scattering, or general relativity, which are sometimes invoked to bridge the gap between the current ambiguous and uncertain theoretical situation and the fact of robust supernova explosions. Since real supernovae occur in three dimensions, our finding may be an important step toward unraveling one of the most problematic puzzles in stellar astrophysics. In addition, even though in 3D, we do see pre-explosion instabilities and blast asymmetries, unlike the situation in 2D, we do not see an obvious axially symmetric dipolar shock oscillation. Rather, the free energy available to power instabilities seems to be shared by more and more degrees of freedom as the dimension increases. Hence, the strong dipolar axisymmetry seen in 2D and previously identified as a fundamental characteristic of the shock hydrodynamics may not survive in 3D as a prominent feature.
Unified N=2 Maxwell-Einstein and Yang-Mills-Einstein Supergravity Theories in Four Dimensions
M. Gunaydin; S. McReynolds; M. Zagermann
2005-07-22T23:59:59.000Z
We study unified N=2 Maxwell-Einstein supergravity theories (MESGTs) and unified Yang-Mills Einstein supergravity theories (YMESGTs) in four dimensions. As their defining property, these theories admit the action of a global or local symmetry group that is (i) simple, and (ii) acts irreducibly on all the vector fields of the theory, including the ``graviphoton''. Restricting ourselves to the theories that originate from five dimensions via dimensional reduction, we find that the generic Jordan family of MESGTs with the scalar manifolds [SU(1,1)/U(1)] X [SO(2,n)/SO(2)X SO(n)] are all unified in four dimensions with the unifying global symmetry group SO(2,n). Of these theories only one can be gauged so as to obtain a unified YMESGT with the gauge group SO(2,1). Three of the four magical supergravity theories defined by simple Euclidean Jordan algebras of degree 3 are unified MESGTs in four dimensions. Two of these can furthermore be gauged so as to obtain 4D unified YMESGTs with gauge groups SO(3,2) and SO(6,2), respectively. The generic non-Jordan family and the theories whose scalar manifolds are homogeneous but not symmetric do not lead to unified MESGTs in four dimensions. The three infinite families of unified five-dimensional MESGTs defined by simple Lorentzian Jordan algebras, whose scalar manifolds are non-homogeneous, do not lead directly to unified MESGTs in four dimensions under dimensional reduction. However, since their manifolds are non-homogeneous we are not able to completely rule out the existence of symplectic sections in which these theories become unified in four dimensions.
Adaptive Projection Subspace Dimension for the Thick-Restart Lanczos Method
Yamazaki, Ichitaro; Bai, Zhaojun; Simon, Horst; Wang, Lin-Wang; Wu, K.
2008-10-01T23:59:59.000Z
The Thick-Restart Lanczos (TRLan) method is an effective method for solving large-scale Hermitian eigenvalue problems. However, its performance strongly depends on the dimension of the projection subspace. In this paper, we propose an objective function to quantify the effectiveness of a chosen subspace dimension, and then introduce an adaptive scheme to dynamically adjust the dimension at each restart. An open-source software package, nu-TRLan, which implements the TRLan method with this adaptive projection subspace dimension is available in the public domain. The numerical results of synthetic eigenvalue problems are presented to demonstrate that nu-TRLan achieves speedups of between 0.9 and 5.1 over the static method using a default subspace dimension. To demonstrate the effectiveness of nu-TRLan in a real application, we apply it to the electronic structure calculations of quantum dots. We show that nu-TRLan can achieve speedups of greater than 1.69 over the state-of-the-art eigensolver for this application, which is based on the Conjugate Gradient method with a powerful preconditioner.
Conformal Bootstrap Approach to O(N) Fixed Points in Five Dimensions
Jin-Beom Bae; Soo-Jong Rey
2014-12-19T23:59:59.000Z
Whether O(N)-invariant conformal field theory exists in five dimensions with its implication to higher-spin holography was much debated. We find an affirmative result on this question by utilizing conformal bootstrap approach. In solving for the crossing symmetry condition, we propose a new approach based on specification for the low-lying spectrum distribution. We find the traditional one-gap bootstrapping is not suited since the nontrivial fixed point expected from large-N expansion sits at deep interior (not at boundary or kink) of allowed solution region. We propose two-gap bootstrapping that specifies scaling dimension of two lowest scalar operators. The approach carves out vast region of lower scaling dimensions and universally features two tips. We find that the sought-for nontrivial fixed point now sits at one of the tips, while the Gaussian fixed point sits at the other tip. The scaling dimensions of scalar operators fit well with expectation based on large-N expansion. We also find indication that the fixed point persist for lower values of N all the way down to N=1. This suggests that interacting unitary conformal field theory exists in five dimensions for all nonzero N.
Magic state distillation in all prime dimensions using quantum Reed-Muller codes
Campbell, Earl T; Browne, Dan E
2012-01-01T23:59:59.000Z
We propose families of protocols for magic state distillation -- important components of fault tolerance schemes --- for systems of odd prime dimension. Our protocols utilize quantum Reed-Muller codes with transversal non-Clifford gates. We find that in higher dimensions smaller codes can be used than one might expect based on qubit codes. All our protocols produce magic states at a resource cost that increases only polynomially with the inverse of the final ouput error probability. We give specific details for 3-dimensional systems, where we find that certain magic states can be distilled provided an initial error probability of less than 20.02% or a depolarizing noise rate of less than 31.7%. This is the largest error probability threshold of all known protocols with polynomial resource cost. For a depolarizing noise model we also give distillation thresholds for odd prime dimensions up-to 19.
Spherical collapse of a heat conducting fluid in higher dimensions without horizon
A. banerjee; S. Chatterjee
2004-06-08T23:59:59.000Z
We consider a scenario where the interior spacetime,described by a heat conducting fluid sphere is matched to a Vaidya metric in higher dimensions.Interestingly we get a class of solutions, where following heat radiation the boundary surface collapses without the appearance of an event horizon at any stage and this happens with reasonable properties of matter field.The non-occurrence of a horizon is due to the fact that the rate of mass loss exactly counterbalanced by the fall of boundary radius.Evidently this poses a counter example to the so-called cosmic censorship hypothesis.Two explicit examples of this class of solutions are also given and it is observed that the rate of collapse is delayed with the introduction of extra dimensions.The work extends to higher dimensions our previous investigation in 4D.
Splitting of 3d quaternion dimensions into 2d-sells and a "world screen technology"
Alexander P. Yefremov
2012-02-14T23:59:59.000Z
A set of basic vectors locally describing metric properties of an arbitrary 2-dimensional (2D) surface is used for construction of fundamental algebraic objects having nilpotent and idempotent properties. It is shown that all possible linear combinations of the objects when multiplied behave as a set of hypercomples (in particular, quaternion) units; thus interior structure of the 3D space dimensions pointed by the vector units is exposed. Geometric representations of elementary surfaces (2D-sells) structuring the dimensions are studied in detail. Established mathematical link between a vector quaternion triad treated as a frame in 3D space and elementary 2D-sells prompts to raise an idea of "world screen" having 1/2 of a space dimension but adequately reflecting kinematical properties of an ensemble of 3D frames.
Omar Maj
2008-02-12T23:59:59.000Z
This is the second part of a work aimed to study complex-phase oscillatory solutions of nonlinear symmetric hyperbolic systems. We consider, in particular, the case of one space dimension. That is a remarkable case, since one can always satisfy the \\emph{naive} coherence condition on the complex phases, which is required in the construction of the approximate solution. Formally the theory applies also in several space dimensions, but the \\emph{naive} coherence condition appears to be too restrictive; the identification of the optimal coherence condition is still an open problem.
Construction and exact solution of a nonlinear quantum field model in quasi-higher dimension
Kundu, Anjan
2015-01-01T23:59:59.000Z
Nonperturbative exact solutions are allowed for quantum integrable models in one space-dimension. Going beyond this class we propose an alternative Lax matrix approach, exploiting the hidden multi-time concept in integrable systems and construct a novel quantum nonlinear Schr\\"odinger model in quasi-two dimensions. An intriguing field commutator is discovered, confirming the integrability of the model and yielding its exact Bethe ansatz solution with rich scattering and bound-state properties. The universality of the scheme is expected to cover diverse models, opening up a new direction in the field.
General Rotating Charged Kaluza-Klein AdS Black Holes in Higher Dimensions
Shuang-Qing Wu
2011-08-21T23:59:59.000Z
I construct exact solutions for general nonextremal rotating, charged Kaluza-Klein black holes with a cosmological constant and with arbitrary angular momenta in all higher dimensions. I then investigate their thermodynamics and find their generalizations with the NUT charges. The metrics are given in both Boyer-Lindquist coordinates and a form very similar to the famous Kerr-Schild ansatz, which highlights its potential application to include multiple electric charges into solutions yet to be found in gauged supergravity. It is also observed that the metric ansatz in $D = 4$ dimensions is similar to those previously suggested by Yilmaz and later by Bekenstein.
Using Muonic Hydrogen in Optical Spectroscopy Experiment to Detect Extra Dimensions
Feng Luo; Hongya Liu
2006-02-23T23:59:59.000Z
Considering that gravitational force might deviate from Newton's inverse-square law (ISL) and become much stronger in small scale, we propose a kind of optical spectroscopy experiment to detect this possible deviation and take electronic, muonic and tauonic hydrogen atoms as examples. This experiment might be used to indirectly detect the deviation of ISL down to nanometer scale and to explore the possibility of three extra dimensions in ADD's model, while current direct gravity tests cannot break through micron scale and go beyond two extra dimensions scenario.
Dimension reduction for anisotropic Bose-Einstein condensates in the strong interaction regime
Weizhu Bao; Loic Le Treust; Florian Mehats
2014-03-12T23:59:59.000Z
We study the problem of dimension reduction for the three dimensional Gross-Pitaevskii equation (GPE) describing a Bose-Einstein condensate confined in a strongly anisotropic harmonic trap. Since the gas is assumed to be in a strong interaction regime, we have to analyze two combined singular limits: a semi-classical limit in the transport direction and the strong partial confinement limit in the transversal direction. We prove that both limits commute together and we provide convergence rates. The by-products of this work are approximated models in reduced dimension for the GPE, with a priori estimates of the approximation errors.
New bounds for the free energy of directed polymers in dimension 1+1 and 1+2
Hubert Lacoin
2009-11-19T23:59:59.000Z
We study the free energy of the directed polymer in random environment in dimension 1+1 and 1+2. For dimension 1, we improve the statement of Comets and Vargas concerning very strong disorder by giving sharp estimates on the free energy at high temperature. In dimension 2, we prove that very strong disorder holds at all temperatures, thus solving a long standing conjecture in the field.
Total Quality Management: Managing the Human Dimension in Natural Resource Agencies1
Standiford, Richard B.
Total Quality Management: Managing the Human Dimension in Natural Resource Agencies1 Denzil Verardo business is conducted in the public sector, and Total Quality Management (TQM) can be the avenue relationships within the DPR and make recommendations for change. Total Quality Management team practices were
Paris-Sud XI, Université de
The dimension of confessionalisation in the Ottoman Balkans at the time of Nationalisms Nathalie identities. However, particularly as far as the Balkan "Christian" nationalisms are concerned, many studies,version1-11Feb2012 Author manuscript, published in "Conflicting loyalties in the Balkans. The Great Powers
Random fractal strings: their zeta functions, complex dimensions and spectral asymptotics
Jordan, Jonathan
Random fractal strings: their zeta functions, complex dimensions and spectral asymptotics B-increasing real numbers which sums to one. For our purposes a fractal string is a string formed from the lengths versions of fractal strings. We show that using a random re- cursive self-similar construction
New Dimensions of Visual Landscape Assessment Wildlands Management for Wildlife Viewing1
Standiford, Richard B.
preservation and other activities associated with traditional game management. Fortunately, much of the knowledge and techniques developed for game #12;management can be transferred to considerations of wildlifeNew Dimensions of Visual Landscape Assessment Wildlands Management for Wildlife Viewing1 Tamsie
Pansu, Pierre
Metric problems in sub-Riemannian geometry Gromov's dimension approach to the H¨older equivalence problem Gromov's cochain approach to the H¨older equivalence problem Rumin's complex Quasisymmetric H¨older-Lipschitz equivalence problem Differential forms and the H¨older equivalence problem P. Pansu September 1st, 2014 P
Variable selection using Adaptive Non-linear Interaction Structures in High dimensions
Radchenko, Peter
superior predictive performance over other approaches. Some key words: Non-Linear Regression; InteractionsVariable selection using Adaptive Non-linear Interaction Structures in High dimensions Peter a tra- ditional linear regression model in which the number of predictors, p, is large relative
Large time behaviour of mild solutions of Hamilton-Jacobi-Bellman equations in infinite dimension
Boyer, Edmond
Large time behaviour of mild solutions of Hamilton-Jacobi-Bellman equations in infinite dimension by a probabilistic approach Ying Hu Pierre-Yves Madec Adrien Richou June 22, 2014 Abstract We study the large time We are concerned with the large time behaviour of solutions of the Cauchy problem in an infinite
GEON: Geophysical data add the 3rd dimension in geospatial studies
Kreinovich, Vladik
GEON: Geophysical data add the 3rd dimension in geospatial studies Aldouri, R.; Keller, G. R of subsurface information to provide a 3-D perspective on data. Geophysical data provide information about projects has required the development of many sophisticated tools to allow users to utilize geophysical
Bounds on the k-dimension of Products of Special Posets
Baym, Michael Hartmann
Trotter conjectured that dimP×Q?dimP+dimQ?2 for all posets P and Q. To shed light on this, we study the k-dimension of products of finite orders. For k???o(ln n), the value 2dimk(P)?dimk(P×P) is unbounded when P is an ...
MAX3SAT Is Exponentially Hard to Approximate If NP Has Positive Dimension
Hitchcock, John
. We will use the hypothesis that NP has positive p-dimension, dimp(NP) > 0. This hypothesis is implied by Âµp(NP) = 0 and implies P = NP. Under the hypothesis dimp(NP) > 0, we give an exponential-time lower but a subexponentially- dense set of satisfiable instances. Put another way, we prove: If dimp(NP) > 0, then any
Gomberoff, Andres; Henneaux, Marc; Teitelboim, Claudio [Centro de Estudios Cientificos (CECS), Valdivia (Chile); Physique Theorique et Mathematique, Universite Libre de Bruxelles and International Solvay Institutes, ULB Campus Plaine C.P. 231, B-1050 Brussels (Belgium); Centro de Estudios Cientificos (CECS), Valdivia (Chile); Centro de Estudios Cientificos (CECS), Valdivia (Chile)
2005-03-15T23:59:59.000Z
We study the decay of the cosmological constant in two spacetime dimensions through production of pairs. We show that the same nucleation process looks as quantum-mechanical tunneling (instanton) to one Killing observer and as thermal activation (thermalon) to another. Thus, we find another striking example of the deep interplay between gravity, thermodynamics and quantum mechanics which becomes apparent in presence of horizons.
Yu, Edward T.
Calculation of critical dimensions for wurtzite and cubic zinc blende coaxial nanowire-shell heterostructures in 111 zinc blende and 0001 wurtzite geometries. These calculations reveal that critical wurtzite nanowire systems. In this article we extend this methodology to explore and contrast coherency
WAVELET SAMPLING AND LOCALIZATION SCHEMES FOR THE RADON TRANSFORM IN TWO DIMENSIONS
Virginia Tech
WAVELET SAMPLING AND LOCALIZATION SCHEMES FOR THE RADON TRANSFORM IN TWO DIMENSIONS SHIYING ZHAO. 57, No. 6, pp. 17491762, December 1997 013 Abstract. Two theorems are presented for wavelet-norm between the Radon transform and its wavelet approximation whose coefficients at different scales
Green's Function for a Hierarchical Self-Avoiding Walk in Four Dimensions
Green's Function for a Hierarchical Self-Avoiding Walk in Four Dimensions David C. Brydges #3 . Apart from completing the program in the #12;rst paper, the main result is that the Green's function is almost equal to the Green's function for the Markov process with no self-repulsion, but at a di#11;erent
A Simple Linear Time (1 + )-Approximation Algorithm for k-Means Clustering in Any Dimensions
Sen, Sandeep
A Simple Linear Time (1 + )-Approximation Algorithm for k-Means Clustering in Any Dimensions Amit@cse.iitd.ernet.in Abstract We present the first linear time (1+)-approximation al- gorithm for the k-means problem for fixed of the most popular definitions of cluster- ing is the k-means clustering problem. Given a set of points P
REGULARISED k-MEANS CLUSTERING FOR DIMENSION REDUCTION APPLIED TO SUPERVISED CLASSIFICATION
McLachlan, Geoff
REGULARISED k-MEANS CLUSTERING FOR DIMENSION REDUCTION APPLIED TO SUPERVISED CLASSIFICATION]. The most popular clustering methods are hierarchical and k-means. However, several key issues for the analysis of large datasets is limited. The procedure k-means is relatively scalable and efficient when
Nanotube Formation: Researchers Learn To Control The Dimensions Of Metal Oxide Nanotubes
Nair, Sankar
made from metal oxides -- work that could lead to a technique for precisely conNanotube Formation: Researchers Learn To Control The Dimensions Of Metal Oxide Nanotubes Science their diameter and length. Based on metal oxides in combination with silicon and germanium, such single
Alternatives to the Seesaw: Extra Z's and Constraints on Large Extra Dimensions
Paul Langacker
2003-04-10T23:59:59.000Z
Alternatives to the traditional grand unified theory seesaw for neutrino masses are briefly described. These include the possibility of large extra dimensions and various possibilities for models involving an extra U(1)' gauge symmetry. The difficulty of observing Majorana phases in neutrinoless double beta decay is also briefly commented on.
Long-ranged forces and energy non-conservation in (1+1)-dimensions
V. A. Rubakov
1997-11-18T23:59:59.000Z
We consider whether local and causal non-conservation of energy may occur in generally covariant theories with long-ranged fields (analogs of Newton's gravity) whose source is energy--momentum. We find that such a possibility exists in (1+1) dimensions.
Optimization of Multiagent Systems with Increasing State Dimensions: Hybrid LQ Approach
Egerstedt, Magnus
been an increasing interest in practically relevant interconnected systems that can be formalized-740, Av. Instituto Politecnico Nacional No. 2508, C.P. 07360, Mexico D.F., Mexico, rgalvan of some groups (networks) of interconnected intelligent machines. The dimension of a robots
Rheingans, Richard
Water insecurity in 3 dimensions: An anthropological perspective on water and women's psychosocial, Rollins School of Public Health, 1518 Clifton Road, Atlanta, GA 30022, USA b Center for Global Safe Water f o Article history: Available online 20 April 2012 Keywords: Water insecurity Gender Psychosocial
Edge states for topological insulators in two dimensions and their Luttinger-like liquids
Denis Bernard; Eun-Ah Kim; André LeClair
2012-09-25T23:59:59.000Z
Topological insulators in three spatial dimensions are known to possess a precise bulk/boundary correspondence, in that there is a one-to-one correspondence between the 5 classes characterized by bulk topological invariants and Dirac hamiltonians on the boundary with symmetry protected zero modes. This holographic characterization of topological insulators is studied in two dimensions. Dirac hamiltonians on the one dimensional edge are classified according to the discrete symmetries of time-reversal, particle-hole, and chirality, extending a previous classification in two dimensions. We find 17 inequivalent classes, of which 11 have protected zero modes. Although bulk topological invariants are thus far known for only 5 of these classes, we conjecture that the additional 6 describe edge states of new classes of topological insulators. The effects of interactions in two dimensions are also studied. We show that all interactions that preserve the symmetries are exactly marginal, i.e. preserve the gaplessness. This leads to a description of the distinct variations of Luttinger liquids that can be realized on the edge.
Topological Insulators in Three Dimensions Liang Fu, C. L. Kane, and E. J. Mele
Kane, Charles
Topological Insulators in Three Dimensions Liang Fu, C. L. Kane, and E. J. Mele Department (STI) topological insulators. The WTI are like layered 2D QSH states, but are destroyed by disorder insulator by a Z2 topological invariant [6], analogous to the TKNN invariant of the integer quantum Hall
Bosonic topological insulator in three dimensions and the statistical Witten effect
Bosonic topological insulator in three dimensions and the statistical Witten effect Max A-known that one signature of the three-dimensional electron topological insulator is the Witten effect-odd-integer polarization charge. In the present work, we propose a corre- sponding phenomenon for the topological insulator
RESEARCH ARTICLE Open Access Social and cultural dimensions of hygiene in
Paris-Sud XI, Université de
RESEARCH ARTICLE Open Access Social and cultural dimensions of hygiene in Cambodian health care on the social and cultural factors that shape hygiene practices in Cambodian health care settings. Methods: We, regarding hygiene practices and social relationships amongst the health care staff and with patients. We
Global dimensions of endomorphism algebras for generator-cogenerators over $m$-replicated algebras
Lv, Hongbo
2008-01-01T23:59:59.000Z
Let $A$ be a finite dimensional hereditary algebra over a field $k$ and $A^{(m)}$ be the $m$-replicated algebra of $A$. We investigate the possibilities for the global dimensions of the endomorphism algebras of generator-cogenerators over $m$-replicated algebra $A^{(m)}$.
Determining the intrinsic dimension of a hyperspectral image using Random Matrix Theory
Damelin, Steven
chemical unmixing [1], extracting speech signals in a noisy line [2], unmixing minerals [3] and unmixing dimension of a hyper- spectral image is an important step in the spectral unmixing process and under the number of sources in a signal is important for the processing of many different types of data, including
A parameter free approach for determining the intrinsic dimension of a hyperspectral image using
Damelin, Steven
chemical unmixing [1], extracting speech signals in a noisy line [2], unmixing minerals [3] and unmixing--Determining the intrinsic dimension of a hyper- spectral image is an important step in the spectral unmixing process the number of sources in a signal is important for the processing of many different types of data, including
INFLUENCE DES DIMENSIONS DE GRAINS SUR L'ANOMALIE DE LA RSISTIVIT DU NICKEL
Boyer, Edmond
L-223 INFLUENCE DES DIMENSIONS DE GRAINS SUR L'ANOMALIE DE LA RÉSISTIVITÉ DU NICKEL AUTOUR DU POINT. 2014 Les mesures de résistivité effectuées sur du nickel formé de cristaux très petits (15 Å, 25 Å) ont grain-sized nickel (15 Å, 25 Å). The critical exponent 03BD and the constant 03BE0 are computed. Results
Evaluation of the first Coulomb Bridge in three dimensions Y. Furutani (*), C. Deutsch
Paris-Sud XI, Université de
of point charges interacting via the Coulomb law in the presence of a neutralizing and mechanically rigidL-285 Evaluation of the first Coulomb Bridge in three dimensions Y. Furutani (*), C. Deutsch to study equilibrium and transport pro- perties in classical and more realistic strongly coupled Coulomb
Estimate for the size of the compactification radius of a one extra dimension universe
Da Rosa, Felipe S [Los Alamos National Laboratory; Pascoal, F [DEPARTAMENTO DE FISICA; Oliveira, L F [CIDADE UNIV; Farina, C [INSTITUTO DE FISICA
2008-01-01T23:59:59.000Z
In this work, we use the Casimir effect to probe the existence of one extra dimension. We begin by evaluating the Casimir pressure between two plates in a M{sup 4} x S{sup 1} manifold, and then use an appropriate statistical analysis in order to compare the theoretical expression with a recent experimental data and set bounds for the compactification radius.
Ecology and the ratchet of events: Climate variability, niche dimensions, and species distributions
Ecology and the ratchet of events: Climate variability, niche dimensions, and species distributionsDepartment of Botany and Program in Ecology and dWyoming Water Resources Data System and Wyoming State Climate Office superimposed on anthropogenic trends. Predicting ecological and biogeographic responses to these changes
DISPERSIVE ESTIMATES FOR SCHR ODINGER OPERATORS IN DIMENSION TWO WITH OBSTRUCTIONS AT ZERO ENERGY
Erdogan, Mehmet
DISPERSIVE ESTIMATES FOR SCHR Â¨ODINGER OPERATORS IN DIMENSION TWO WITH OBSTRUCTIONS AT ZERO ENERGY for the SchrÂ¨odinger operator H = -+V when there are obstructions, resonances or an eigenvalue, at zero energy. In particular, we show that the existence of an s-wave resonance at zero energy does not destroy the t-1 decay
Dimensions of identity Within an international network of researchers, le Rseau d'tudes
Paris-Sud XI, UniversitÃ© de
Dimensions of identity Within an international network of researchers, le RÃ©seau d'Ã©tudes sur le journalisme (the Network for journalism studies), we have developed this conception of journalism RUELLAN UniversitÃ© de Rennes, France ABSTRACT Thinking of journalism in new ways should be free of any
Paris-Sud XI, Université de
Towards an interaction evaluation between dimensions and objectives of sustainable development states, along with governments from around the world, have affirmed support for sustainable development, recently agreeing that the developed countries must take the lead in securing a "shift towards sustainable
Optimizing moderator dimensions for neutron scattering at the spallation neutron source
Zhao, J. K.; Robertson, J. L.; Herwig, Kenneth W.; Gallmeier, Franz X.; Riemer, Bernard W. [Instrument and Source Division, Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Instrument and Source Division, Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)
2013-12-15T23:59:59.000Z
In this work, we investigate the effect of neutron moderator dimensions on the performance of neutron scattering instruments at the Spallation Neutron Source (SNS). In a recent study of the planned second target station at the SNS facility, we have found that the dimensions of a moderator play a significant role in determining its surface brightness. A smaller moderator may be significantly brighter over a smaller viewing area. One of the immediate implications of this finding is that for modern neutron scattering instrument designs, moderator dimensions and brightness have to be incorporated as an integrated optimization parameter. Here, we establish a strategy of matching neutron scattering instruments with moderators using analytical and Monte Carlo techniques. In order to simplify our treatment, we group the instruments into two broad categories: those with natural collimation and those that use neutron guide systems. For instruments using natural collimation, the optimal moderator selection depends on the size of the moderator, the sample, and the moderator brightness. The desired beam divergence only plays a role in determining the distance between sample and moderator. For instruments using neutron optical systems, the smallest moderator available that is larger than the entrance dimension of the closest optical element will perform the best (assuming, as is the case here that smaller moderators are brighter)
Neutrinoless double beta decay constrained by the existence of large extra dimensions
Marek Gó?d?; W. A. Kami?ski
2012-01-05T23:59:59.000Z
We present the possible influence on the half-life of neutrinoless double beta decay coming from the existence of $n$ extra spatial dimensions. The half-life in question depends on the mass of the electron neutrino. We base our analysis on the Majorana neutrino mass mechanism in Arkani-Hamed--Dimopoulos--Dvali model.
Politècnica de Catalunya, Universitat
hampering the deployment of transparent optical networks (i.e., no electrical signal regenerators at minimiz- ing the number of electrical regenerators deployed in the network. To tackle it, in this paper and dimensioning problem in sub-wavelength switching optical networks Oscar Pedrola a,b, , Davide Careglio
Purely electric spin pumping in one-dimension Yshai Avishai1,3
Cohen, Doron
Purely electric spin pumping in one-dimension Yshai Avishai1,3 , Doron Cohen1 and Naoto Nagaosa2 1 (such as metallic wire) can display quantum spin pumping possibly without pushing any charge each period. This is referred to as quantum (charge) pumping [1Â5]. In recent years, the concept
Purely Electric Spin Pumping in One Dimension Yshai Avishai,1,2
Cohen, Doron
Purely Electric Spin Pumping in One Dimension Yshai Avishai,1,2 Doron Cohen,1 and Naoto Nagaosa3 1-dimensional system (such as metallic wire) can display quantum spin pumping possibly without pushing any charge to as quantum (charge) pumping [1Â5]. In recent years, pumping of spin polariza- tion has become a focus
Castorina, P.; Zappala, D. [Department of Physics, University of Catania and INFN Sezione di Catania, Via S. Sofia 64, I 95123, Catania (Italy); INFN Sezione di Catania, Via S. Sofia 64, I 95123, Catania (Italy)
2008-01-15T23:59:59.000Z
The spontaneous breaking of translational invariance in noncommutative self-interacting scalar field theory in two dimensions is investigated by effective action techniques. The analysis confirms the existence of the stripe phase, already observed in lattice simulations, due to the nonlocal nature of the noncommutative dynamics.
Agmon, Noam
on the level of the manybody theory employed. The survival probability in the simple ``Superposition Approxi problem'' 6 of a static A molecule, the Smoluchowski theory is actually exact. Even when A is mobile, the devia tions from the theory are small, 6,7 particularly in higher di mensions #e.g., three dimensions
Effective sea-level rise and deltas: Causes of change and human dimension implications
New Hampshire, University of
Effective sea-level rise and deltas: Causes of change and human dimension implications Jason P January 2006 Abstract An assessment is made of contemporary effective sea-level rise (ESLR) for a sample of eustatic sea-level rise, the natural gross rate of fluvial sediment deposition and subsidence
TRACKING TONGUE MOTION IN THREE DIMENSIONS USING TAGGED MR IMAGES Xiaofeng Liu1
Prince, Jerry L.
TRACKING TONGUE MOTION IN THREE DIMENSIONS USING TAGGED MR IMAGES Xiaofeng Liu1 , Maureen Stone3 and strain analysis of tagged magnetic res- onance (MR) imaging [1]. It was originally applied to car- diac This research was supported by NIH grants R01 HL047405 and R01 DC001758 (a) (b) Fig. 1. (a) A tagged MR image
QUESTIONS ON WILD Z/pZ-QUOTIENT SINGULARITIES IN DIMENSION 2
Lorenzini, Dino J.
QUESTIONS ON WILD Z/pZ-QUOTIENT SINGULARITIES IN DIMENSION 2 DINO LORENZINI 1. Some questions Let A is called a wild cyclic quotient singularity. Let f : X Z be a resolution of the singularity, minimal a terminal chain. Wild Z/pZ-quotient singularities of surfaces are expected to have resolution graphs which
Bashir, Rashid
dimensions and profiles R. Bashir,a),b) A. E. Kabir,b) F. Hebert,c) and C. Brackenb) National Semiconductors. In many applications a spacer needs to be formed on the polycide sidewall Fig. 1 . Undesirable undercutting can re- sult in nonideal spacer formation for further device fabrica- tion. Tungsten silicide
Fractal dimension based sand ripple suppression for mine hunting with sidescan sonar
Nelson, James
mine hunting. Manual inspection of such data can be a time consuming task that requires significant1 Fractal dimension based sand ripple suppression for mine hunting with sidescan sonar J. D. B. Nelson and N. G. Kingsbury Abstract--Sand ripples present a difficult challenge to current mine hunting
Stationary free surface viscous ows without surface tension in three dimensions
Paris-Sud XI, Université de
Stationary free surface viscous ows without surface tension in three dimensions Frederic Abergel owing down a three dimensional channel. In the absence of surface tension, we prove the existence is not elliptic when surface tension is neglected. Hence, analysis such as that made in [4] or [17] fails
Stationary free surface viscous flows without surface tension in three dimensions
Boyer, Edmond
Stationary free surface viscous flows without surface tension in three dimensions Frederic Abergel dimensional channel. In the absence of surface tension, we prove the existence of a unique stationary solution is not elliptic when surface tension is neglected. Hence, analysis such as that made in [4] or [17] fails
Unified N=2 Maxwell-Einstein and Yang-Mills-Einstein Supergravity Theories in Four Dimensions
Günaydin, M; Zagermann, M
2005-01-01T23:59:59.000Z
We study unified N=2 Maxwell-Einstein supergravity theories (MESGTs) and unified Yang-Mills Einstein supergravity theories (YMESGTs) in four dimensions. As their defining property, these theories admit the action of a global or local symmetry group that is (i) simple, and (ii) acts irreducibly on all the vector fields of the theory, including the ``graviphoton''. Restricting ourselves to the theories that originate from five dimensions via dimensional reduction, we find that the generic Jordan family of MESGTs with the scalar manifolds [SU(1,1)/U(1)] X [SO(2,n)/SO(2)X SO(n)] are all unified in four dimensions with the unifying global symmetry group SO(2,n). Of these theories only one can be gauged so as to obtain a unified YMESGT with the gauge group SO(2,1). Three of the four magical supergravity theories defined by simple Euclidean Jordan algebras of degree 3 are unified MESGTs in four dimensions. Two of these can furthermore be gauged so as to obtain 4D unified YMESGTs with gauge groups SO(3,2) and SO(6,2)...
The fractality of lung sounds: A comparison of three waveform fractal dimension algorithms
Moussavi, Zahra M. K.
The fractality of lung sounds: A comparison of three waveform fractal dimension algorithms January of flow-specific lung sounds (LS) have been compared to examine the fractal nature of these signals. LS between LS in health and disease. Ó 2005 Elsevier Ltd. All rights reserved. 1. Introduction Lung sounds
Predicting Pattern Tooling and Casting Dimensions for Investment Casting - Phase II
Sabau, Adrian S [ORNL
2005-09-01T23:59:59.000Z
The investment casting process allows the production of complex-shape parts and close dimensional tolerances. One of the most important phases in the investment casting process is the design of the pattern die. Pattern dies are used to create wax patterns by injecting wax into dies. The wax patterns are used to create a ceramic shell by the application of a series of ceramic coatings, and the alloy is cast into the dewaxed shell mold (Fig. 1.1). However, the complexity of shape and the close dimensional tolerances required in the final casting make it difficult to determine tooling dimensions. The final linear dimension of the casting depends on the cumulative effects of the linear expansions or contractions in each step of the investment casting process (Fig. 1.2). In most cases, the mold geometry or cores restrict the shrinkage of the pattern or the cast part, and the final casting dimensions may be affected by time-dependent processes such as viscoelastic deformation of the wax, and viscoplastic creep and plastic deformations of the shell and alloy. The pattern die is often reworked several times to produce castings whose dimensions are within acceptable tolerances. To date, investment casting technology has been based on hands-on training and experience. Technical literature is limited to experimental, phenomenological studies aimed at obtaining empirical correlations for quick and easy application in industry. The goal of this project was to predict casting dimensions for investment castings in order to meet blueprint nominal during the first casting run. Several interactions have to be considered in a coupled manner to determine the shrinkage factors: these are the die-wax, wax-shell, and shell-alloy interactions (as illustrated in Fig. 1.3). In this work, the deformations of the die-wax and shell-alloy systems were considered in a coupled manner, while the coupled deformation of the wax-shell system was not considered. Future work is needed in order to deliver to industry a computer program in which all three systems are coupled for determining the dimensions of the wax pattern, the shell mold, and casting in a sequential but coupled manner.
Prasanta Kumar Das; V H Satheeshkumar; P. K. Suresh
2008-08-20T23:59:59.000Z
In large extra dimensional Kaluza-Klein (KK) scenario, where the usual Standard Model (SM) matter is confined to a 3+1-dimensional hypersurface called the 3-brane and gravity can propagate to the bulk (D=4+d, d being the number of extra spatial dimensions), the light graviton KK modes can be produced inside the supernova core due to the usual nucleon-nucleon bremstrahlung, electron-positron and photon-photon annihilations. This photon inside the supernova becomes plasmon due to the plasma effect. In this paper, we study the energy-loss rate of SN 1987A due to the KK gravitons produced from the plasmon-plasmon annihilation. We find that the SN 1987A cooling rate leads to the conservative bound $M\\_D$ > 22.9 TeV and 1.38 TeV for the case of two and three space-like extra dimensions.
Hydrogen atom in space with a compactified extra dimension and potential defined by Gauss' law
Martin Bureš; Petr Siegl
2014-09-30T23:59:59.000Z
We investigate the consequences of one extra spatial dimension for the stability and energy spectrum of the non-relativistic hydrogen atom with a potential defined by Gauss' law, i.e. proportional to $1/|x|^2$. The additional spatial dimension is considered to be either infinite or curled-up in a circle of radius $R$. In both cases, the energy spectrum is bounded from below for charges smaller than the same critical value and unbounded from below otherwise. As a consequence of compactification, negative energy eigenstates appear: if $R$ is smaller than a quarter of the Bohr radius, the corresponding Hamiltonian possesses an infinite number of bound states with minimal energy extending at least to the ground state of the hydrogen atom.
SU(N) gauge theories in 2+1 dimensions -- further results
B. Lucini; M. Teper
2002-06-24T23:59:59.000Z
We calculate the string tension and part of the mass spectrum of SU(4) and SU(6) gauge theories in 2+1 dimensions using lattice techniques. We combine these new results with older results for N=2,...,5 so as to obtain more accurate extrapolations to N=infinity. The qualitative conclusions of the earlier work are unchanged: SU(N) theories in 2+1 dimensions are linearly confining as N->infinity; the limit is achieved by keeping g.g.N fixed; SU(3), and even SU(2), are `close' to SU(infinity). We obtain more convincing evidence than before that the leading large-N correction is O(1/N.N). We look for the multiplication of states that one expects in simple flux loop models of glueballs, but find no evidence for this.
Family symmetry and single right-handed neutrino dominance in five dimensions
Eisele, Marc-Thomas; Haba, Naoyuki [Physik-Department, Technische Universitaet Muenchen, James-Franck-Strasse, 85748 Garching (Germany)
2006-10-01T23:59:59.000Z
We consider several neutrino mass models in an extra-dimensional setting on a quantitative level. All the models are set in a five-dimensional scenario, with the standard model (SM) particles living on a brane, while three additional SM gauge singlets live in the bulk of an extra dimension, which is compactified on a S{sup 1}/Z{sub 2} orbifold. The spontaneous breaking of an additional, continuous U(1) family symmetry is used to generate suitable neutrino mass matrices via single right-handed neutrino dominance through the corresponding five-dimensional extension of the seesaw mechanism. In this manner, possible problems of this combination for some models in four dimensions could be overcome. The considered models differ with respect to the charges under the family symmetry and the nature of the five-dimensional Majorana mass term.
Holographic fractional topological insulators in 2+1 and 1+1 dimensions
Andreas Karch; Joseph Maciejko; Tadashi Takayanagi
2010-11-09T23:59:59.000Z
We give field theory descriptions of the time-reversal invariant quantum spin Hall insulator in 2+1 dimensions and the particle-hole symmetric insulator in 1+1 dimensions in terms of massive Dirac fermions. Integrating out the massive fermions we obtain a low-energy description in terms of a topological field theory, which is entirely determined by anomaly considerations. This description allows us to easily construct low-energy effective actions for the corresponding `fractional' topological insulators, potentially corresponding to new states of matter. We give a holographic realization of these fractional states in terms of a probe brane system, verifying that the expected topologically protected transport properties are robust even at strong coupling.
On Thermodynamics of AdS Black Holes in Arbitrary Dimensions
A. Belhaj; M. Chabab; H. El Moumni; M. B. Sedra
2012-09-23T23:59:59.000Z
Considering the cosmological constant $\\Lambda$ as a thermodynamic pressure and its conjugate quantity as a thermodynamic volume as proposed in Kubiznak and Mann (2012), we discuss the critical behavior of charged AdS black hole in arbitrary dimensions $d$. In particular, we present a comparative study in terms of the spacetime dimension $d$ and the displacement of critical points controlling the transition between the small and the large black holes. Such behaviors vary nicely in terms of $d$. Among our result in this context consists in showing that the equation of state for a charged RN-AdS black hole predicts an universal number given by $\\frac{2d-5}{4d-8}$. The three dimensional solution is also discussed.
Search for large extra spatial dimensions in dimuon production at D0
Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, M.; Adams, T.; Agelou, M.; Agram, J.-L.; Ahn, S.H.; Ahsan, M.; Alexeev, G.D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G.A.; Anastasoaie, M.; Andeen, T.; Anderson, S.; Andrieu, B.; Arnoud, Y.; Askew, A.; /Buenos Aires U. /Rio de Janeiro, CBPF /Rio de Janeiro State U. /Sao
2005-06-01T23:59:59.000Z
We present the results of a search for the e.ects of large extra spatial dimensions in p{bar p} collisions at {radical}s = 1.96 TeV in events containing a pair of energetic muons. The data correspond to 246 pb{sup -1} of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron Collider. Good agreement with the expected background was found, yielding no evidence for large extra dimensions. We set 95% C.L. lower limits on the fundamental Planck scale between 0.85 TeV and 1.27 TeV within several formalisms. These are the most stringent limits achieved in the dimuon channel to date.
Quantization of Space and Time in 3 and in 4 Space-time Dimensions
G. 't Hooft
1996-08-16T23:59:59.000Z
The fact that in Minkowski space, space and time are both quantized does not have to be introduced as a new postulate in physics, but can actually be derived by combining certain features of General Relativity and Quantum Mechanics. This is demonstrated first in a model where particles behave as point defects in 2 space dimensions and 1 time, and then in the real world having 3+1 dimensions. The mechanisms in these two cases are quite different, but the outcomes are similar: space and time form a (non-cummutative) lattice. These notes are short since most of the material discussed in these lectures is based on two earlier papers by the same author (gr-qc/9601014 and gr-qc/9607022), but the exposition given in the end is new.
BSM Primary Effects: The complete set of predictions from the dimension-6 BSM Lagrangian
Rick S. Gupta
2014-07-31T23:59:59.000Z
We present a physical parameterization of the leading effects beyond the SM (BSM), that give us, at present, the best way to constrain heavy new-physics at low-energies. We call these effects that constrain all possible interactions at the dimension 6 level, BSM Primary effects; there are 8 primaries related to Higgs physics, 3 related to Triple Gauge Couplings and 7 related to Z- pole measurements at LEP. Starting from these experimentally measurable deformations (and not operators), we construct the dimension 6 Lagrangian in a bottom up way. We, thus, show that other BSM effects are not independent from the primary ones and we provide the explicit correlations. We also discuss the theoretical expectation for the size of these BSM primaries in some well-motivated BSM theories.
Reconstruction of ionization probabilities from spatially averaged data in N dimensions
Strohaber, J.; Kolomenskii, A. A.; Schuessler, H. A. [Department of Physics, Texas A and M University, College Station, Texas 77843-4242 (United States)
2010-07-15T23:59:59.000Z
We present an analytical inversion technique, which can be used to recover ionization probabilities from spatially averaged data in an N-dimensional detection scheme. The solution is given as a power series in intensity. For this reason, we call this technique a multiphoton expansion (MPE). The MPE formalism was verified with an exactly solvable inversion problem in two dimensions, and probabilities in the postsaturation region, where the intensity-selective scanning approach breaks down, were recovered. In three dimensions, ionization probabilities of Xe were successfully recovered with MPE from simulated (using the Ammosov-Delone-Krainov tunneling theory) ion yields. Finally, we tested our approach with intensity-resolved benzene-ion yields, which show a resonant multiphoton ionization process. By applying MPE to this data (which were artificially averaged), the resonant structure was recovered, which suggests that the resonance in benzene may have been observed in spatially averaged data taken elsewhere.
Statistics of the gravitational force in various dimensions of space: from Gaussian to Levy laws
Pierre-Henri Chavanis
2009-07-28T23:59:59.000Z
We discuss the distribution of the gravitational force created by a Poissonian distribution of field sources (stars, galaxies,...) in different dimensions of space d. In d=3, it is given by a Levy law called the Holtsmark distribution. It presents an algebraic tail for large fluctuations due to the contribution of the nearest neighbor. In d=2, it is given by a marginal Gaussian distribution intermediate between Gaussian and Levy laws. In d=1, it is exactly given by the Bernouilli distribution (for any particle number N) which becomes Gaussian for N>>1. Therefore, the dimension d=2 is critical regarding the statistics of the gravitational force. We generalize these results for inhomogeneous systems with arbitrary power-law density profile and arbitrary power-law force in a d-dimensional universe.
PACKING DIMENSION OF THE RANGE OF A LEVY PROCESS DAVAR KHOSHNEVISAN AND YIMIN XIAO
Khoshnevisan, Davar
, normalized so that E[exp(izX(t))] = exp(-t(z)) for all t 0 and z Rd , and let dimP denote the packing dimension (Tricot, 1982; Sullivan, 1984). Taylor (1986) has proved that with probability one, dimP X([0 , 1 is to describe = dimP X([0 , 1]) more explicitly than (0.1), and solely in terms of the LÂ´evy exponent . For all
Baca, David Ray
2007-04-25T23:59:59.000Z
DIMENSIONS OF SERVICE QUALITY OF THE UNIVERSITY OF ARIZONA SPONSORED PROJECTS SERVICES OFFICE INTERNAL CUSTOMERS A Dissertation by DAVID RAY BACA Submitted to the Office of Graduate Studies of Texas A&M University in partial... CUSTOMERS A Dissertation by DAVID RAY BACA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of the Committee...
New Einstein Metrics in Dimension Five Charles P. Boyer Krzysztof Galicki
New Einstein Metrics in Dimension Five Charles P. Boyer Krzysztof Galicki Abstract: The purpose of this note is to prove the existence of new SasakianÂEinstein metÂ rics on S 2 \\ThetaS 3 and on (S 2 \\ThetaS 3 )#(S 2 \\ThetaS 3 ): These give the first known examples of nonÂregular SasakianÂEinstein 5
A Simple Linear Time (1 + #)Approximation Algorithm for kMeans Clustering in Any Dimensions
Kumar, Amit
A Simple Linear Time (1 + #)ÂApproximation Algorithm for kÂMeans Clustering in Any Dimensions Amit@cse.iitd.ernet.in Abstract We present the first linear time (1+#)Âapproximation alÂ gorithm for the kÂmeans problem for fixed of the most popular definitions of clusterÂ ing is the kÂmeans clustering problem. Given a set of points P
Effect of uneven sampling on correlation dimension computed from time series data
Sandip V. George; G. Ambika; R. Misra
2014-10-16T23:59:59.000Z
Observational data, especially astrophysical data, is often limited by uneven sampling that arises due to lack of observations for a variety of reasons. Such inadvertent gaps are usually smoothed over using interpolation techniques. However the smoothing techniques can introduce artificial effects, especially when non-linear analysis is undertaken. We investigate how uneven sampling can affect the computed values of correlation dimension of the system, without using any interpolation. For this we introduce gaps artificially in synthetic data derived from standard chaotic systems, like the Rossler and Lorenz, with frequency of occurrence and size of missing data drawn from Gaussian distributions. Then we study the changes in correlation dimension with change in the distributions of frequency of gaps introduced and size of data removed. We find that for a considerable range of gap frequency and size, the value of correlation dimension is not significantly affected. This would mean that in such specific cases, the calculated values can still be reliable and acceptable. Thus our study introduces a method of checking the reliability of computed correlation dimension values by calculating the distribution of gaps with respect to its size and frequency and comparing with the standard plots presented in the paper. This is illustrated for real world examples of the data from three variable stars, R Scuti, U Monocerotis and SU Tauri. We also demonstrate how a cubic spline interpolation can cause an unevenly sampled noisy data to be misinterpreted as being chaotic in origin. This is demonstrated for the non chaotic light curve of variable star SS Cygni, which gives a saturated D2 value, when interpolated using a cubic spline.
Simple thermodynamics of strongly coupled one-component-plasma in two and three dimensions
Khrapak, Sergey A., E-mail: Sergey.Khrapak@dlr.de [Forschungsgruppe Komplexe Plasmen, Deutsches Zentrum für Luft- und Raumfahrt, Oberpfaffenhofen (Germany); Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation); Khrapak, Alexey G. [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation)
2014-10-15T23:59:59.000Z
Simple analytical approximations for the internal energy of the strongly coupled one-component-plasma in two and three dimensions are discussed. As a result, new practical expressions for the internal energy in the fluid phase are proposed. Their accuracy is checked by evaluating the location of the fluid-solid phase transition from the free energy consideration. Possible applications to other related systems are briefly discussed.
Black hole radiation of spin-1 particles in (1+2) dimensions
S. I. Kruglov
2014-11-26T23:59:59.000Z
The radiation of vector particles by black holes in (1+2) dimensions is investigated within the WKB approximation. We consider the process of quantum tunnelling of bosons through an event horizon of the black hole. The emission temperature for the Schwarzschild background geometry coincides with the Hawking temperature and for the Rindler spacetime the temperature is the Unruh temperature. We also obtain the radiation temperatures for the de Sitter spacetime.
QCD condensates of dimension D=6 and D=8 from hadronic tau-decays
A. A. Almasy; K. Schilcher; H. Spiesberger
2006-12-22T23:59:59.000Z
The high-precision data from hadronic tau decays allows one to extract information on QCD condensates. Using the finalized ALEPH data, we obtain a more rigorous determination of the dimension 6 and 8 condensates for the V-A correlator. In particular, we find that the recent data fix a certain linear combination of these QCD condensates to a precision at the level of O(2%). Our approach relies on more general assumptions than alternative approaches based on finite energy sum rules.
Computing Characteristics of One Class of Non-commutative Hypercomplex Number Systems of 4-dimension
Yakiv O. Kalinovsky; Dmitry V. Lande; Yuliya E. Boyarinova; Alina S. Turenko
2014-09-09T23:59:59.000Z
The class of non-commutative hypercomplex number systems (HNS) of 4-dimension constructed by using of non-commutative procedure of Grassman-Clifford doubling of 2-dimensional systems is investigated in the article. All HNS of this class are constructed, algorithms of performance of operations and methods of algebraic characteristics calculation in them, such as conjugation, normalization, a type of zero dividers are investigated. Formulas of exponential functions representation in these systems are displayed.
Optimizing Moderator Dimensions for Neutron Scattering at the Spallation Neutron Source
Zhao, Jinkui [ORNL; Robertson, Lee [ORNL; Herwig, Kenneth W [ORNL; Gallmeier, Franz X [ORNL; Riemer, Bernie [ORNL
2013-01-01T23:59:59.000Z
In this work, we investigate the effect of neutron moderator dimensions on the performance of neutron scattering instruments at the Spallation Neutron Source. In a recent study of the planned second target station at the Spallation Neutron Source (SNS) facility [1,2], we have found that the dimensions of a moderator play a significant role in determining its surface brightness. A smaller moderator may be significantly brighter for a smaller viewing area [4]. One of the immediate implications of this finding is that for modern neutron scattering instrument designs, moderator dimensions and brightness have to be incorporated as an integrated optimization parameter. Here, we establish a strategy of matching neutron scattering instruments with moderators using analytical and Monte Carlo techniques. In order to simplify our treatment, we group the instruments into two broad categories, those with natural collimation and those that use neutron guide systems. We found that the cross-sections of the sample and the neutron guide, respectively, are the deciding factors for choosing the moderator. Beam divergence plays no role as long as it is within the reach of practical constraints. Namely, the required divergence is not too large for the guide or sample to be located close enough to the moderator on an actual spallation source.
The effective chiral Lagrangian from dimension-six parity and time-reversal violation
Vries, J. de, E-mail: devries.jordy@gmail.com [KVI, Theory Group, University of Groningen, 9747 AA Groningen (Netherlands); Nikhef, Science Park 105, 1098 XG Amsterdam (Netherlands); Mereghetti, E. [Ernest Orlando Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States)] [Ernest Orlando Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States); Timmermans, R.G.E. [KVI, Theory Group, University of Groningen, 9747 AA Groningen (Netherlands)] [KVI, Theory Group, University of Groningen, 9747 AA Groningen (Netherlands); Kolck, U. van [Institut de Physique Nucléaire, Université Paris Sud, CNRS/IN2P3, 91406 Orsay (France) [Institut de Physique Nucléaire, Université Paris Sud, CNRS/IN2P3, 91406 Orsay (France); Department of Physics, University of Arizona, Tucson, AZ 85721 (United States)
2013-11-15T23:59:59.000Z
We classify the parity- and time-reversal-violating operators involving quark and gluon fields that have effective dimension six: the quark electric dipole moment, the quark and gluon chromo-electric dipole moments, and four four-quark operators. We construct the effective chiral Lagrangian with hadronic and electromagnetic interactions that originate from them, which serves as the basis for calculations of low-energy observables. The form of the effective interactions depends on the chiral properties of these operators. We develop a power-counting scheme and calculate within this scheme, as an example, the parity- and time-reversal-violating pion–nucleon form factor. We also discuss the electric dipole moments of the nucleon and light nuclei. -- Highlights: •Classification of T-odd dimension-six sources based on impact on observables. •Building of the chiral Lagrangian for each dimension-six source. •Calculation of the PT-odd pion–nucleon form factor for each source. •Discussion of hadronic EDMs for each source and comparison with the theta term.
Schweik, Charles M.
Department of Environmental Conservation, University of Massachusetts-Amherst Concentration in Environmental Policy and Human Dimensions 1 Environmental Conservation Graduate Program Environmental Policy Master of Science (MS) and Doctor of Philosophy (PhD) degrees in Environmental Conservation (ECo
DeBartolo, Jack, III
1994-01-01T23:59:59.000Z
This thesis addresses the experiential dimension of architecture as it relates to the dynamics of light and the universal presence of the phenomenal. The effort is to (re)imagine the environment: to behold the pageantry ...
Sergey V. Yakovlev
2011-12-21T23:59:59.000Z
Were investigated anisotropic metric of higher dimensional space-time with only cosmological term and scalar field. Showed, that presence of scalar field is equivalent to anisotropic metric in the multy dimensional space-time and proposed idea of dimensions generation by scalar field. Were solved Einstein's equations for higher dimensional space-time of Kazner's type and derived expressions for density of energy for scalar field, which generate additional dimensions, and proposed the procedure of renormalization of the metric.
Couch, Sean M., E-mail: smc@flash.uchicago.edu [Flash Center for Computational Science, Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States)
2013-09-20T23:59:59.000Z
We present one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) hydrodynamical simulations of core-collapse supernovae including a parameterized neutrino heating and cooling scheme in order to investigate the critical core neutrino luminosity (L{sub crit}) required for explosion. In contrast to some previous works, we find that 3D simulations explode later than 2D simulations, and that L{sub crit} at fixed mass accretion rate is somewhat higher in three dimensions than in two dimensions. We find, however, that in two dimensions L{sub crit} increases as the numerical resolution of the simulation increases. In contrast to some previous works, we argue that the average entropy of the gain region is in fact not a good indicator of explosion but is rather a reflection of the greater mass in the gain region in two dimensions. We compare our simulations to semi-analytic explosion criteria and examine the nature of the convective motions in two dimensions and three dimensions. We discuss the balance between neutrino-driven buoyancy and drag forces. In particular, we show that the drag force will be proportional to a buoyant plume's surface area while the buoyant force is proportional to a plume's volume and, therefore, plumes with greater volume-to-surface-area ratios will rise more quickly. We show that buoyant plumes in two dimensions are inherently larger, with greater volume-to-surface-area ratios, than plumes in three dimensions. In the scenario that the supernova shock expansion is dominated by neutrino-driven buoyancy, this balance between buoyancy and drag forces may explain why 3D simulations explode later than 2D simulations and why L{sub crit} increases with resolution. Finally, we provide a comparison of our results with other calculations in the literature.
E. Elizalde; S. D. Odintsov; A. A. Saharian
2011-02-10T23:59:59.000Z
We investigate the fermionic condensate and the vacuum expectation value of the energy-momentum tensor for a massive fermionic field in the geometry of two parallel plate on the background of Minkowski spacetime with an arbitrary number of toroidally compactified spatial dimensions, in the presence of a constant gauge field. Bag boundary conditions are imposed on the plates and periodicity conditions with arbitrary phases are considered along the compact dimensions. The boundary induced parts in the fermionic condensate and the vacuum energy density are negative, with independence of the phases in the periodicity conditions and of the value of the gauge potential. Interaction forces between the plates are thus always attractive. However, in physical situations where the quantum field is confined to the region between the plates, the pure topological part contributes as well, and then the resulting force can be either attractive or repulsive, depending on the specific phases encoded in the periodicity conditions along the compact dimensions, and on the gauge potential, too. Applications of the general formulas to cylindrical carbon nanotubes are considered, within the framework of a Dirac-like theory for the electronic states in graphene. In the absence of a magnetic flux, the energy density for semiconducting nanotubes is always negative. For metallic nanotubes the energy density is positive for long tubes and negative for short ones. The resulting Casimir forces acting on the edges of the nanotube are attractive for short tubes with independence of the tube chirality. The sign of the force for long nanotubes can be controlled by tuning the magnetic flux. This opens the way to the design of efficient actuators driven by the Casimir force at the nanoscale.
Non-Relativistic Parity-Violating Hydrodynamics in Two Spatial Dimensions
Matthias Kaminski; Sergej Moroz
2014-04-01T23:59:59.000Z
We construct the non-relativistic parity-violating hydrodynamic description of a two-dimensional dissipative, normal fluid in presence of small U(1) background fields and vorticity. This is achieved by taking the non-relativistic limit of the recently developed relativistic hydrodynamics in 2+1 dimensions. We identify and interpret the resulting parity-violating contributions to the non-relativistic constitutive relations, which include the Hall current flowing perpendicular to the temperature gradient, the Hall viscosity and the Leduc-Righi energy current. Also a comparison of our findings is made with the non-relativistic parity-violating hydrodynamics obtained from a light-cone dimensional reduction.
Geometry of the Uniform Spanning Forest: Transitions in Dimensions 4, 8, 12
Itai Benjamini; Harry Kesten; Yuval Peres; Oded Schramm
2003-02-13T23:59:59.000Z
The uniform spanning forest (USF) in Z^d is the weak limit of random, uniformly chosen, spanning trees in [-n,n]^d. Pemantle proved that the USF consists a.s. of a single tree if and only if d = 9. More generally, let N(x,y) be the minimum number of edges outside the USF in a path joining x and y in Z^d. Then a.s. max{N(x,y) : x,y in Z^d} is the integer part of (d-1)/4. The notion of stochastic dimension for random relations in the lattice is introduced and used in the proof.
Analytical solutions of a generalized non-central potential in N-dimensions
Durmus, Aysen, E-mail: aysend@erciyes.edu.tr [Department of Physics, Erciyes University, Kayseri 38039 (Turkey); Özfidan, Aysel [Institute of Science, Erciyes University, Kayseri 38039 (Turkey)
2014-10-15T23:59:59.000Z
We present that N-dimensional non-relativistic wave equation for the generalized non-central potential with arbitrary angular momentum is analytically solvable in the hyperspherical coordinates. Asymptotic iteration method as a different approach is applied to obtain N-dimensional energy eigenvalues and the corresponding eigenfunctions. In hyperspherical coordinates, the wave function solutions are obtained in terms of hypergeometric functions and Jacobi polynomials. The bound states of quantum systems under consideration for some special cases, such as Hartmann and Makarov potentials, have been discussed in N-dimensions.
On the vacua of N = 8 gauged supergravity in 4 dimensions
G. Dall'Agata; G. Inverso
2012-01-23T23:59:59.000Z
We discuss a simple procedure for finding vacua of gauged supergravity models, based on the variation of the embedding tensor rather than on a direct minimization of the scalar potential. We apply this procedure to N=8 gauged supergravity in 4 dimensions. We easily recover many of the previously known vacua, also completing their scalar mass spectrum, and we apply our procedure to find a dozen of new analytical vacuum solutions. The analysis shows an interesting structure on the moduli spaces of these vacua and provides new criteria to determine the expected value of the cosmological constant by a simple inspection of the group properties of the embedding tensor.
Fermion Pair Production From an Electric Field Varying in Two Dimensions
J. E. Seger; A. B. Balantekin
1995-06-26T23:59:59.000Z
The Hamiltonian describing fermion pair production from an arbitrarily time-varying electric field in two dimensions is studied using a group-theoretic approach. We show that this Hamiltonian can be encompassed by two, commuting SU(2) algebras, and that the two-dimensional problem can therefore be reduced to two one-dimensional problems. We compare the group structure for the two-dimensional problem with that previously derived for the one-dimensional problem, and verify that the Schwinger result is obtained under the appropriate conditions.
The high-temperature behavior for the directed polymer in dimension 1+2
Quentin Berger; Hubert Lacoin
2015-06-30T23:59:59.000Z
We investigate the high-temperature behavior of the directed polymer model in dimension $1+2$. More precisely we study the difference $\\Delta \\mathtt{F}(\\beta)$ between the quenched and annealed free energies for small values of the inverse temperature $\\beta$. This quantity is associated to localization properties of the polymer trajectories, and is related to the overlap fraction of two replicas. Adapting recent techniques developed by the authors in the context of the disordered pinning model (Berger and Lacoin, arXiv:1503.07315 [math-ph]), we identify the sharp asymptotic high temperature behavior \\[\\lim_{\\beta\\to 0} \\, \\beta^2 \\log \\Delta \\mathtt{F}(\\beta) = -\\pi \\, .\\
Scaling exponents for a monkey on a tree - fractal dimensions of randomly branched polymers
Hans-Karl Janssen; Olaf Stenull
2012-03-13T23:59:59.000Z
We study asymptotic properties of diffusion and other transport processes (including self-avoiding walks and electrical conduction) on large randomly branched polymers using renormalized dynamical field theory. We focus on the swollen phase and the collapse transition, where loops in the polymers are irrelevant. Here the asymptotic statistics of the polymers is that of lattice trees, and diffusion on them is reminiscent of the climbing of a monkey on a tree. We calculate a set of universal scaling exponents including the diffusion exponent and the fractal dimension of the minimal path to 2-loop order and, where available, compare them to numerical results.
Stability of charged thin-shell wormholes in (2 + 1) dimensions
Ayan Banerjee
2013-10-20T23:59:59.000Z
In this paper we construct charged thin-shell wormholes in (2+1)-dimensions applying the cut-and -paste technique implemented by Visser, from a BTZ black hole which was discovered by Banados, Teitelboim and Zanelli, and the surface stress are determined using the Darmois-Israel formalism at the wormhole throat. We analyzed the stability of the shell considering phantom-energy or generalised Chaplygin gas equation of state for the exotic matter at the throat. We also discussed the linearized stability of charged thin-shell wormholes around the static solution.
Non-local correction to the energy-momentum tensor for $?^{3}$ theory in six dimensions
Feng Wu
2015-05-07T23:59:59.000Z
Applying the background field method, we construct by explicit computation the leading-order nonlocal quantum correction to the on-shell effective action for $\\phi^3$ theory in six dimensions. We then use the resulting action to obtain the nonlocal correction to the energy-momentum tensor. At leading order, we find that this nonlocal correction modified the virial current when the scalar field is minimally coupled to gravity. On the contrary, it only corrects the traceless part of the energy-momentum tensor in the classically Weyl invariant case.
Overdamped thermal ratchets in one and more dimensions. Kinesin transport and protein folding
Ernesto Gonzalez-Candela; Victor Romero-Rochin
2006-05-26T23:59:59.000Z
The overdamped thermal ratchet driven by an external (Orstein-Uhlenbeck) noise is revisited. The ratchet we consider is unbounded in space and not necessarily periodic . We briefly discuss the conditions under which current is obtained by analyzing the corresponding Fokker-Planck equation and its lack of stationary states. Next, two examples in more than one dimension and related to biological systems are presented. First, a two-dimensional model of a ``kinesin protein'' on a ``microtubule'' is analyzed and, second, we suggest that a ratchet mechanism may be behind the folding of proteins; the latter is elaborated with a multidimensional ratchet model.
Flat space cosmologies in two dimensions - Phase transitions and asymptotic mass-domination
Arjun Bagchi; Daniel Grumiller; Jakob Salzer; Sourav Sarkar; Friedrich Schöller
2014-08-22T23:59:59.000Z
We study flat space cosmologies in two dimensions by taking the flat space limit of the Achucarro-Ortiz model. We unravel a phase transition between hot flat space and flat space cosmologies, and derive a new dilaton-dependent counterterm required for the consistency of the Euclidean partition function. Our results generalize to asymptotically mass-dominated 2-dimensional dilaton gravity models, whose thermodynamical properties we discuss. The novel case of asymptotic mass-domination is neither covered by the comprehensive discussion of hep-th/0703230 nor by the more recent generalization to dilaton gravity with confining U(1) charges in 1406.7007.
Canonical Formulation of Gravitational Teleparallelism in 2+1 Dimensions in Schwinger's Time Gauge
A. A. Sousa; J. W. Maluf
2000-12-21T23:59:59.000Z
We consider the most general class of teleparallel gravitational {}{}theories quadratic in the torsion tensor, in three space-time dimensions, and carry out a detailed investigation of its Hamiltonian formulation in Schwinger's time gauge. This general class is given by a family of three-parameter theories. A consistent implementation of the Legendre transform reduces the original theory to a one-parameter family of theories. By calculating Poisson brackets we show explicitly that the constraints of the theory constitute a first-class set. Therefore the resulting theory is well defined with regard to time evolution. The structure of the Hamiltonian theory rules out the existence of the Newtonian limit.
Novel Spacetime Concept and Dimension Curling up Mechanism in Neon Shell
Kunming Xu
2005-11-02T23:59:59.000Z
Euclidean geometry does not characterize dynamic electronic orbitals satisfactorily for even a single electron in a hydrogen atom is a formidable mathematical task with the Schrodinger equation. Here the author puts forward a new spacetime concept that regards space and time as two orthogonal, symmetric and complementary quantities. They are inherent physical quantities that cannot be divorced from physical objects themselves. In two-dimensional helium shell, space and time are instantiated by two interactive 1s electrons; in four-dimensional neon shell, space and time dimensions blend into four types of curvilinear vectors represented by 2s, 2px, 2py, and 2pz electronic orbitals. The description of electronic orbitals constitutes an explanation of canonical spacetime properties such as harmonic oscillation, electromagnetism, and wave propagation. Through differential and integral operations, the author formulates a precise wavefunction for every electron in an inert neon atom where spacetime, as dimensional graduated by ten electrons, is continuous, and trigonometric function is the mechanism for dimension curling up. This fresh spacetime view based on dimensional interpretation of complex functions is an extension of classical mechanics and is compatible with relativity and quantum physics. It brings sharp insight into the geometries of 2p-orbitals and has broad support from chemistry.
Accelerating universe from gravitational leakage into extra dimensions: confrontation with SNeIa
Zong-Hong Zhu; Jailson S. Alcaniz
2004-11-01T23:59:59.000Z
There is mounting observational evidence that the expansion of our universe is undergoing an acceleration. A dark energy component has usually been invoked as the most feasible mechanism for the acceleration. However, it is desirable to explore alternative possibilities motivated by particle physics before adopting such an untested entity. In this work, we focus our attention on an acceleration mechanism: one arising from gravitational leakage into extra dimensions. We confront this scenario with high-$z$ type Ia supernovae compiled by Tonry et al. (2003) and recent measurements of the X-ray gas mass fractions in clusters of galaxies published by Allen et al. (2002,2003). A combination of the two databases gives at a 99% confidence level that $\\Omega_m=0.29^{+0.04}_{-0.02}$, $\\Omega_{rc}=0.21^{+0.08}_{-0.08}$, and $\\Omega_k=-0.36^{+0.31}_{-0.35}$, indicating a closed universe. We then constrain the model using the test of the turnaround redshift, $z_{q=0}$, at which the universe switches from deceleration to acceleration. We show that, in order to explain that acceleration happened earlier than $z_{q=0} = 0.6$ within the framework of gravitational leakage into extra dimensions, a low matter density, $\\Omega_m < 0.27$, or a closed universe is necessary.
Large Extra Dimension effects through Light-by-Light Scattering at the CERN LHC
Hao Sun
2014-07-31T23:59:59.000Z
Observing light-by-light scattering at the Large Hadron Collider (LHC) has received quite some attention and it is believed to be a clean and sensitive channel to possible new physics. In this paper, we study the diphoton production at the LHC via the process $\\rm pp\\rightarrow p\\gamma\\gamma p\\rightarrow p\\gamma\\gamma p$ through graviton exchange in the Large Extra Dimension (LED) model. Typically, when we do the background analysis, we also study the Double Pomeron Exchange (DPE) of $\\gamma\\gamma$ production. We compare its production in the quark-quark collision mode to the gluon-gluon collision mode and find that contributions from the gluon-gluon collision mode are comparable to the quark-quark one. Our result shows, for extra dimension $\\delta=4$, with an integrated luminosity $\\rm {\\cal L} = 200 fb^{-1}$ at the 14 TeV LHC, that diphoton production through graviton exchange can probe the LED effects up to the scale $\\rm M_S=5.06 (4.51, 5.11) TeV$ for the forward detector acceptance $\\xi_1 (\\xi_2, \\xi_3)$, respectively, where $0.00150.5$, $0.10.5$ and $0.0015<\\xi_3<0.15$.
Proton decay via dimension-six operators in intersecting D6-brane models
Mirjam Cvetic; Robert Richter
2006-08-04T23:59:59.000Z
We analyze the proton decay via dimension six operators in supersymmetric SU(5)-Grand Unified models based on intersecting D6-brane constructions in Type IIA string theory orientifolds. We include in addition to 10* 10 10* 10 interactions also the operators arising from 5-bar* 5-bar 10* 10 interactions. We provide a detailed construction of vertex operators for any massless string excitation arising for arbitrary intersecting D-brane configurations in Type IIA toroidal orientifolds. In particular, we provide explicit string vertex operators for the 10 and 5-bar chiral superfields and calculate explicitly the string theory correlation functions for above operators. In the analysis we chose the most symmetric configurations in order to maximize proton decay rates for the above dimension six operators and we obtain a small enhancement relative to the field theory result. After relating the string proton decay rate to field theory computations the string contribution to the proton lifetime is tau^{ST}_p =(0.5-2.1) x 10^{36} years, which could be up to a factor of three shorter than that predicted in field theory.
ILD SiW ECAL and sDHCAL dimension-performance optimisation
Tran, Trong Hieu
2014-01-01T23:59:59.000Z
The ILD, International Large Detector, is one of the detector concepts for a future linear collider. Its performance is investigated using Monte-Carlo full simulation and PandoraPFA. Among several options, a combination of the silicon-tungsten electromagnetic calorimeter (SiW ECAL) and the semi-digital hadronic calorimeter (sDHCAL) presenting the highest granularity calorimeters, is here investigated. It is shown that by reducing the radius and length of the entire detector by a factor of $\\sim1.3$ with respect to the baseline dimensions, the jet energy resolution is degraded by 8 to 19% in the range of 45 and 250 GeV. The price of ILD which scales roughly quadratically with the ILD dimensions may be reduced by a factor of nearly two. A similar study made with the SiW ECAL and the analog hadronic calorimeter (AHCAL) shows that for an inner radius of ECAL of about~1.4 m, the performance is comparable between sDHCAL and AHCAL.
Weapons proliferation and organized crime: The Russian military and security force dimension
Turbiville, G.H.
1996-06-01T23:59:59.000Z
One dimension of international security of the post-Cold War era that has not received enough attention is how organized crime facilitates weapons proliferation worldwide. The former Soviet Union (FSU) has emerged as the world`s greatest counterproliferation challenge. It contains the best developed links among organized crime, military and security organizations, and weapons proliferation. Furthermore, Russian military and security forces are the principle source of arms becoming available to organized crime groups, participants in regional conflict, and corrupt state officials engaged in the black, gray, and legal arms markets in their various dimensions. The flourishing illegal trade in conventional weapons is the clearest and most tangible manifestation of the close links between Russian power ministries and criminal organizations. The magnitude of the WMD proliferation problem from the FSU is less clear and less tangible. There have been many open reports of small-scale fissile material smuggling out of the FSU. The situation with regard to the proliferation of chemical weapon usually receives less attention but may be more serious. With an acknowledged stockpile of 40,000 metric tons of chemical agents, the potential for proliferation is enormous.
Cornering dimension-6 $HVV$ interactions at high luminosity LHC: the role of event ratios
Banerjee, Shankha; Mellado, Bruce; Mukhopadhyaya, Biswarup
2015-01-01T23:59:59.000Z
We suggest a way of improving the probes on dimension-6 CP-conserving $HVV$ interactions ($V$ = $W$, $Z$, $\\gamma$), from the LHC data on the Higgs boson to be available in the 14 TeV run with an integrated luminosity of $3000$ fb$^{-1}$. We find that the ratios of total rates in different channels can be quite useful in this respect. This includes ratios of event rates in (a) different final states for the Higgs produced by the same production mechanism, and (b) the same final state from two different production modes. While most theoretical uncertainties cancel in the former, the latter helps in the case of those operators which shift the numerator and denominator in opposite directions. Our analysis, incorporating theoretical, systematic and statistical uncertainties, leads to projected limits that are better than the strongest ones obtained so far from precision electroweak as well as LHC Higgs data. Moreover, values of the coefficients of the dimension-6 operators, which are allowed in disjoint intervals...
Cosmology in one dimension: Symmetry role in dynamics, mass oriented approaches to fractal analysis
Miller, Bruce N; Shiozawa, Yui
2015-01-01T23:59:59.000Z
The distribution of visible matter in the universe, such as galaxies and galaxy clusters, has its origin in the week fluctuations of density that existed at the epoch of recombination. The hierarchical distribution of the universe, with its galaxies, clusters and super-clusters of galaxies indicates the absence of a natural length scale. In the Newtonian formulation, numerical simulations of a one-dimensional system permit us to precisely follow the evolution of an ensemble of particles starting with an initial perturbation in the Hubble flow. The limitation of the investigation to one dimension removes the necessity to make approximations in calculating the gravitational field and, on the whole, the system dynamics. It is then possible to accurately follow the trajectories of particles for a long time. The simulations show the emergence of a self-similar hierarchical structure in both the phase space and the configuration space and invites the implementation of a multifractal analysis. Here, after showing th...
Regge Field Theory in zero transverse dimensions: loops versus "net" diagrams
Sergey Bondarenko
2010-11-22T23:59:59.000Z
Toy models of interacting Pomerons with triple and quaternary Pomeron vertices in zero transverse dimension are investigated. Numerical solutions for eigenvalues and eigenfunctions of the corresponding Hamiltonians are obtained, providing the quantum solution for the scattering amplitude in both models. The equations of motion for the Lagrangians of the theories are also considered and the classical solutions of the equations are found. Full two-point Green functions ("effective" Pomeron propagator) and amplitude of diffractive dissociation process are calculated in the framework of RFT-0 approach. The importance of the loops contribution in the amplitude at different values of the model parameters is discussed as well as the difference between the models with and without quaternary Pomeron vertex.
Phenomenology of non-relativistic parity-violating hydrodynamics in 2+1 dimensions
Andrew Lucas; Piotr Surówka
2014-12-09T23:59:59.000Z
Parity-violating fluids in two spatial dimensions can appear in a variety of contexts such as liquid crystal films, anyon fluids, and quantum Hall fluids. Nonetheless, the consequences of parity-violation on the solutions to the equations of motion are largely unexplored. In this paper, we explore phenomenological consequences of parity-violation through simple, illustrative examples. Although incompressible velocity fields are essentially unchanged by parity violation, we discuss examples where parity violation plays a role at boundaries, or in the dynamics of temperature. We then discuss new types of compressible flows which only exist in a parity-violating fluid, including new sound waves, and solitons in the dissipationless limit. We conclude with a discussion of some curious features in Rayleigh-B\\'enard convection of a parity-violating fluid.
Anomalous dimensions determine the power counting -- Wilsonian RG analysis of nuclear EFT --
Koji Harada; Hirofumi Kubo
2006-10-24T23:59:59.000Z
The Legendre flow equation, a version of exact Wilsonian renormalization group (WRG) equation, is employed to consider the power counting issues in Nuclear Effective Field Theory. A WRG approach is an ideal framework because it is nonperturbative and does not require any prescribed power counting rule. The power counting is determined systematically from the scaling dimensions of the operators at the nontrivial fixed point. The phase structure is emphasized and the inverse of the scattering length, which is identified as a relevant coupling, is shown to play a role of the order parameter. The relations to the work done by Birse, McGovern, and Richardson and to the Kaplan-Savage-Wise scheme are explained.
Ozgur Akarsu; Tekin Dereli; Nihan Katirci; Mikhail B. Sheftel
2015-05-04T23:59:59.000Z
In a recent study Akarsu and Dereli (Gen. Relativ. Gravit. 45:1211, 2013) discussed the dynamical reduction of a higher dimensional cosmological model which is augmented by a kinematical constraint characterized by a single real parameter, correlating and controlling the expansion of both the external (physical) and internal spaces. In that paper explicit solutions were found only for the case of three dimensional internal space ($n=3$). Here we derive a general solution of the system using Lie group symmetry properties, in parametric form for arbitrary number $n=1,2,3,\\dots$ of internal dimensions. We also investigate the dynamical reduction of the model as a function of cosmic time $t$ for various values of $n$ and generate parametric plots to discuss cosmologically relevant results.
Image patch analysis of sunspots and active regions. I. Intrinsic dimension and correlation analysis
Moon, Kevin R; Delouille, Veronique; De Visscher, Ruben; Watson, Fraser; Hero, Alfred O
2015-01-01T23:59:59.000Z
Complexity of an active region is related to its flare-productivity. Mount Wilson or McIntosh sunspot classifications measure such complexity but in a categorical way, and may therefore not use all the information present in the observations. Moreover, such categorical schemes hinder a systematic study of an active region's evolution for example. We propose fine-scale quantitative descriptors for an active region's complexity and relate them to the Mount Wilson classification. We analyze the local correlation structure within continuum and magnetogram data, as well as the cross-correlation between continuum and magnetogram data. We compute the intrinsic dimension, partial correlation, and canonical correlation analysis (CCA) of image patches of continuum and magnetogram active region images taken from the SOHO-MDI instrument. We use masks of sunspots derived from continuum as well as larger masks of magnetic active regions derived from the magnetogram to analyze separately the core part of an active region fr...
General analytic solution of R sup 2 gravity with dynamical torsion in two dimensions
Kummer, W.; Schwarz, D.J. (Institut fuer Theoretische Physik, Technische Universitaet Wien, Wiedner Haupstrasse 8-10, A-1040 Wien (Austria))
1992-05-15T23:59:59.000Z
Using light-cone variables, we show that {ital R}{sup 2} gravity with dynamical torsion in two dimensions is one of the rare field theories whose {ital complete} classical solution in closed form can be obtained. It fulfils an invariant relation between the cosmological constant, the curvature scalar, and the scalar formed by the torsion tensor. We conjecture that this relation, interpreted as a local conservation law, is closely connected to the integrability of the theory. The solutions may possess a rich spectrum of singularities in curvature and torsion. Special cases, including one with nonvanishing torsion, can be used to elucidate some physical properties of the solution where by physical'' we imply the validity of concepts from general relativity such as measurements of distances and times and of extremal trajectories of a scalar test particle.
Tilli, Andrea; Conficoni, Christian
2011-01-01T23:59:59.000Z
In this chapter some results related to Shunt Active Filters (SAFs) and obtained by the authors and some coauthors are reported. SAFs are complex power electronics equipments adopted to compensate for cur-rent harmonic pollution in electric mains, due to nonlinear loads. By using a proper "floating" capacitor as energy reservoir, the SAF purpose is to inject in the line grid currents canceling the polluting har-monics. Control algorithms play a key role for such devices and, in general, in many power electronics applications. Moreover, systems theory is crucial, since it is the mathematical tool that enables a deep understanding of the involved dynamics of such systems, allowing a correct dimensioning, beside an effective control. As a matter of facts, current injection objective can be straightforwardly formulated as an output tracking control problem. In this fashion, the structural and insidious marginally-stable internal/zero dynamics of SAFs can be immediately highlighted and characterized in terms of si...
Critical dimension sensitivity to post-exposure bake temperaturevariation in EUV photoresists
Cain, Jason P.; Naulleau, Patrick; Spanos, Costas J.
2005-01-11T23:59:59.000Z
Chemically amplified resists depend upon the post-exposure bake (PEB) process to drive the deprotection reactions (in positive resists) that lead to proper resist development. For this reason they often exhibit critical dimension (CD) sensitivity to PEB temperature variation. In this work the effects of variation in different aspects of the PEB step on post-develop CD are studied for two extreme ultraviolet (EUV) photoresists. The spatial and temporal temperature uniformity of the PEB plate is measured using a wireless sensor wafer. Programmed variations in the bake plate temperature set point are then used to measure the CD sensitivity to steady state temperature variation. In addition, the initial temperature ramp time is modified using a thin sheet of polyimide film between the wafer and the bake plate. This allows for measurement of the CD sensitivity to transient temperature variation. Finally, the bake time is adjusted to measure the CD sensitivity to this parameter.
Shearer's point process and the hard-sphere model in one dimension
Christoph Hofer-Temmel
2015-04-10T23:59:59.000Z
We revisit the smallest non-physical singularity of the hard-sphere model in one dimension, also known as Tonks gas. We give an explicit expression of the free energy and reduced correlations at negative real fugacity and elaborate the nature of the singularity: the free energy is right-continuous, but its derivative diverges. We derive these results in several novel ways: First, by scaling up the discrete solution. Second, by an inductive argument on the partition function \\`a la Dobrushin. Third, by a perfect cluster expansion counting the Penrose trees in the Mayer expansion perfectly. Fourth, by an explicit construction of Shearer's point process, the unique R-dependent point process with an R-hard-core. The last connection yields explicit and optimal lower bounds on the avoidance function of R-dependent point processes on the real line.
Holographic Superconductors in 3+1 dimensions away from the probe limit
Yves Brihaye; Betti Hartmann
2010-04-15T23:59:59.000Z
We study holographic superconductors in 3+1 dimensions away from the probe limit, i.e. taking back-reaction of the space-time into account. We consider the case of pure Einstein- and Gauss-Bonnet gravity, respectively. Similar to the probe limit we observe that the critical temperature at which condensation sets in decreases with increasing Gauss-Bonnet coupling. The decrease is however stronger when taking back-reaction of the space-time into account. We observe that the critical temperature becomes very small, but stays positive for all values of the Gauss-Bonnet coupling no matter how strong the back-reaction of the space-time is.
Free Energy and Plaquette expectation value for gluons on the lattice, in three dimensions
H. Panagopoulos; A. Skouroupathis; A. Tsapalis
2006-02-24T23:59:59.000Z
We calculate the perturbative value of the Free Energy in Lattice QCD in three dimensions, up to three loops. Our calculation is performed using the Wilson formulation for gluons in SU(N) gauge theories. The Free Energy is directly related to the average plaquette. To carry out the calculation, we compute the coefficients involved in the perturbative expansion of the Free Energy up to three loops, using an automated set of procedures developed by us in Mathematica. The dependence on N is shown explicitly in our results. For purposes of comparison, we also present the individual contributions from every diagram. These have been obtained by means of two independent calculations, in order to cross check our results.
Sean P. Robinson
2006-09-17T23:59:59.000Z
We calculate, in d spacetime dimensions, the relationship between the coefficient 1/K^2 of the Einstein-Hilbert term in the action of general relativity and the coefficient G_N of the force law that results from the Newtonian limit of general relativity. The result is K^2=2[(d-2)/(d-3)]Vol(S^[d-2])G_N, where Vol(S^n) is the volume of the unit n-sphere. While the d=4 case is an elementary calculation in any general relativity text, the arbitrary case presented here is slightly less well known. We discuss the relevance of this result for the definition of the so-called "reduced Planck mass" and comment very briefly on the implications for brane world models. [abstract abridged
Accelerating Taub-NUT and Eguchi-Hanson solitons in four dimensions
Chng, Brenda [Department of Physics, National University of Singapore 2 Science Drive 3, Singapore 117542 (Singapore); Mann, Robert [Perimeter Institute for Theoretical Physics 31 Caroline St. N. Waterloo, Ontario N2L 2Y5 (Canada); Department of Physics, University of Waterloo 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada); Stelea, Cristian [Department of Physics, University of Waterloo 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada)
2006-10-15T23:59:59.000Z
We construct new solutions of the vacuum Einstein field equations in four dimensions via a solution-generating method utilizing the SL(2,R) symmetry of the reduced Lagrangian. We apply the method to an accelerating version of the Zipoy-Voorhees solution and generate new solutions which we interpret to be the accelerating versions of the Zipoy-Voorhees generalization of the Taub-NUT solution (with Lorentzian signature) and the Zipoy-Voorhees generalization of the Eguchi-Hanson solitons (with Euclidean signature). As an intermediary in the solution-generating process we obtain charged versions of the accelerated Zipoy-Voorhees-like families of solutions. Finally we present the accelerating version of the Taub-NUT solution and discuss its properties.
Accelerating Taub-NUT and Eguchi-Hanson solitons in four dimensions
Brenda Chng; Robert Mann; Cristian Stelea
2006-08-19T23:59:59.000Z
We construct new solutions of the vacuum Einstein field equations in four dimensions via a solution generating method utilizing the SL(2,R) symmetry of the reduced Lagrangian. We apply the method to an accelerating version of the Zipoy-Voorhees solution and generate new solutions which we interpret to be the accelerating versions of the Zipoy-Voorhees generalisation of the Taub-NUT solution (with Lorentzian signature) and the Zipoy-Voorhees generalisation of the Eguchi-Hanson solitons (with Euclidean signature). As an intermediary in the solution-generating process we obtain charged versions of the accelerated Zipoy-Voorhees-like families of solutions. Finally we present the accelerating version of the Taub-NUT solution and discuss its properties.
Hur, Jin [School of Computational Sciences, Korea Institute for Advanced Study, Seoul 130-012 (Korea, Republic of); Min, Hyunsoo [Department of Physics, University of Seoul, Seoul 130-743 (Korea, Republic of); School of Physics, Korea Institute for Advanced Study, Seoul 130-012 (Korea, Republic of)
2008-06-15T23:59:59.000Z
Recently the partial-wave cutoff method was developed as a new calculational scheme for a functional determinant of quantum field theory in radial backgrounds. For the contribution given by an infinite sum of large partial waves, we derive explicitly radial-WKB series in the angular momentum cutoff for d=2, 3, 4, and 5 (d is the space-time dimension), which has uniform validity irrespectively of any specific values assumed for other parameters. Utilizing this series, precision evaluation of the renormalized functional determinant is possible with a relatively small number of low partial-wave contributions determined separately. We illustrate the power of this scheme in a numerically exact evaluation of the prefactor (expressed as a functional determinant) in the case of the false vacuum decay of 4D scalar field theory.
All bulk and boundary unitary cubic curvature theories in three dimensions
Guellue, Ibrahim; Sisman, Tahsin Cagri; Tekin, Bayram [Department of Physics, Middle East Technical University, 06531, Ankara (Turkey)
2011-01-15T23:59:59.000Z
We construct all the bulk and boundary unitary cubic curvature parity invariant gravity theories in three dimensions in (anti)-de Sitter spaces. For bulk unitarity, our construction is based on the principle that the free theory of the cubic curvature theory reduces to one of the three known unitary theories which are the cosmological Einstein-Hilbert theory, the quadratic theory of the scalar curvature, or the new massive gravity (NMG). Bulk and boundary unitarity in NMG is in conflict; therefore, cubic theories that are unitary both in the bulk and on the boundary have free theories that reduce to the other two alternatives. We also study the unitarity of the Born-Infeld extensions of NMG to all orders in curvature.
Neuronal micro-culture engineering by microchannel devices of cellular scale dimensions
Goyal, Gaurav
2015-01-01T23:59:59.000Z
Purpose: The purpose of the current study was to investigate the effect of microchannel geometry on neuronal cultures and to maintain these cultures for long period of time (over several weeks) inside the closed microchannels of cellular scale dimensions. Methods: The primary hippocampal neurons from E-18 rat were cultured inside the closed polydimethylsiloxane (PDMS) microchannels of varying sizes. The effect of the channel geometry on the spatial and the temporal variations in the neural microenvironment was investigated by studying neural maturation and variation in the media osmolality respectively. The cultures were maintained for longer time spans by PDMS device pretreatment, control on media evaporation (by using hydrophobic ethylene propylene membrane) and an effective culture maintenance protocol. Further, the devices were integrated with the planar microelectrode arrays (MEA) to record spontaneous electrical activity. Results: A direct influence of channel geometry on neuron maturation was observed ...
Causal dissipative hydrodynamics for QGP fluid in 2+1 dimensions
A. K. Chaudhuri
2007-08-01T23:59:59.000Z
In 2nd order causal dissipative theory, space-time evolution of QGP fluid is studied in 2+1 dimensions. Relaxation equations for shear stress tensors are solved simultaneously with the energy-momentum conservation equations. Comparison of evolution of ideal and viscous QGP fluid, initialized under the same conditions, e.g. same equilibration time, energy density and velocity profile, indicate that in a viscous dynamics, energy density or temperature of the fluid evolve slowly, than in an ideal fluid. Cooling gets slower as viscosity increases. Transverse expansion also increases in a viscous dynamics. For the first time we have also studied elliptic flow of 'quarks' in causal viscous dynamics. It is shown that elliptic flow of quarks saturates due to non-equilibrium correction to equilibrium distribution function, and can not be mimicked by an ideal hydrodynamics.
Virial Theorem for Non-relativistic Quantum Fields in D Spatial Dimensions
Lin, Chris L
2015-01-01T23:59:59.000Z
The virial theorem for non-relativistic complex fields in $D$ spatial dimensions and with arbitrary many-body potential is derived, using path-integral methods and scaling arguments recently developed to analyze quantum anomalies in lower-dimensional systems. The potential appearance of a Jacobian $J$ due to a change of variables in the path-integral expression for the partition function of the system is pointed out, although in order to make contact with the literature most of the analysis deals with the $J=1$ case. The virial theorem is recast into a form that displays the effect of microscopic scales on the thermodynamics of the system. From the point of view of this paper the case usually considered, $J=1$, is not natural, and the generalization to the case $J\
Peng Ye; Zheng-Cheng Gu
2014-11-20T23:59:59.000Z
Bosonic topological insulators (BTI) in three spatial dimensions are symmetry protected topological (SPT) phases with U(1)$\\rtimes$Z$^T_2$ symmetry, where U(1) is boson particle number conservation, and Z$^T_2$ is time-reversal symmetry with $\\mathcal{T}^2=1$. BTI were first proposed based on the group cohomology theory which suggests two distinct root states, each carrying a $\\mathbb{Z}_2$ index. Soon after, surface anomalous topological orders were proposed to identify different root states of BTI, leading to a new BTI root state beyond the group cohomology classification. Nevertheless, it is still unclear what is the universal physical mechanism for BTI phases and what kinds of microscopic Hamiltonians can realize them. In this paper, we answer the first question by proposing a universal physical mechanism via vortex-line condensation in a superfluid, which can potentially be realized in realistic systems, e.g., helium-4 or cold atoms in optical lattices. Using such a simple physical picture, we find three root phases, of which two of them are classified by group cohomology theory while the other is beyond group cohomology classification. The physical picture also leads to a "natural" bulk dynamic topological quantum field theory (TQFT) description for BTI phases and gives rise to a possible physical pathway towards experimental realizations. Finally, we generalize the vortex-line condensation picture to other symmetries and find that in three dimensions, even for a unitary Z$_2$ symmetry, there could be a nontrivial Z$_2$ SPT phase beyond the group cohomology classification.
Peffer, Therese; Arens, Edward A; Chen, Xue; Jang, Jaehwi; Auslander, David M.
2008-01-01T23:59:59.000Z
and Ed Arens. 2008. Demand Response-Enabled ResidentialEfficiency and Demand Response Programs for 2005/2006.The Human Dimension of Demand Response Enabling Technology
How to Use the Dimension Elite 3D Printer (in the Carnegie Mellon MechE Machine Shop)
McGaughey, Alan
How to Use the Dimension Elite 3D Printer (in the Carnegie Mellon MechE Machine Shop) The 3D printer is in the undergraduate area of the shop, by the safety glasses, lasercutters, etc. 2) Login to the computer beside the 3D printer using your Andrew username and password (Note: at the time
``Problem Set Six'' (1) In free scalar field theory in four dimensions, with mass m, calculate ij + \\Sigma ij , where \\Sigma ij , the ``selfÂenergy,'' is to be computed from loops. A very fundamental property of \\Sigma ij is that in momentum space k i \\Sigma ij (k) = 0. (An explanation of why
Christopher Shirley
2014-09-30T23:59:59.000Z
The purpose of the present work is to establish decorrelation estimates at distinct energies for some random Schr\\"odinger operator in dimension one. In particular, we establish the result for some random operators on the continuum with alloy-type potential. These results are used to give a description of the spectral statistics.
Lozano-Robledo, Alvaro
Formulas & definitions to know Formulas & definitions that will be provided if needed Distance formula in 3 dimensions compab = aÂ·b |a| Equation of a sphere W = F Â· D (work, force, distance) Vector of differentiability for a function of two variables arc length formula, arc length function the graph of a function
I. Radinschi; Th. Grammenos
2005-08-01T23:59:59.000Z
We use Moeller's energy-momentum complex in order to explicitly compute the energy and momentum density distributions for an exact solution of Einstein's field equations with a negative cosmological constant minimally coupled to a static massless scalar field in a static, spherically symmetric background in (2+1)-dimensions.
Phase transitions for N-electron atoms at the large-dimension limit Pablo Serra* and Sabre Kais
Kais, Sabre
that involve a nonzero latent heat and radical change of the structure of the material at the transition points. Second- order phase transitions are continuous phase changes where the properties of the system doPhase transitions for N-electron atoms at the large-dimension limit Pablo Serra* and Sabre Kais
Gray, Wayne
dynamic corpora such as the World Wide Web. There have been some attempts to reduce the vector-based form to allow these measures to evaluate relatedness of multi-word terms (documents, paragraphs). We. With the resulting dimension sets, VGEM matches or outperforms the probability-based measure, while adding the multi-word
sprays. _____ 7. I do not litter. _____ 8. I volunteer my time for environmental conservation projectsWhat is Your Environmental Wellness? The environmental dimension involves accepting the impact we points _____ 1. I consciously conserve energy (electricity, heat, light, water, etc.) in my place
Ringel, Claus Michael
The global dimension of the endomorphism ring of a generator-cogenerator for a hereditary artin a -module which is both a generator and a cogenerator. We are going to describe the possibilities is called a generator if any projective module belongs to add M; it is called a cogenerator if any injective