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Sample records for average api gravity

  1. A Complete Cosmological Solution to the Averaged Einstein Field Equations as found in Macroscopic Gravity

    E-Print Network [OSTI]

    R. J. van den Hoogen

    2009-09-01

    A formalism for analyzing the complete set of field equations describing Macroscopic Gravity is presented. Using this formalism, a cosmological solution to the Macroscopic Gravity equations is determined. It is found that if a particular segment of the connection correlation tensor is zero and if the macroscopic geometry is described by a flat Robertson-Walker metric, then the effective correction to the averaged Einstein Field equations of General Relativity i.e., the backreaction, is equivalent to a positive spatial curvature term. This investigation completes the analysis of [Phys. Rev. Lett., vol. 95, 151102, (2005)] and the formalism developed provides a possible basis for future studies.

  2. Glossary API Gravity: An

    U.S. Energy Information Administration (EIA) Indexed Site

    Finished motor gaso- line formulated for use in motor vehicles, the composition and properties of which meet the requirements of the reformulated gasoline regu- Energy...

  3. Glossary API Gravity: An

    U.S. Energy Information Administration (EIA) Indexed Site

    Finished motor gaso- line formulated for use in motor vehicles, the composition and properties of which meet the requirements of the reformulated gasoline regulations...

  4. Glossary API Gravity: An

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb Mar Apr MayYear Jan Feb Mar87.1CubicYear Jan Feb2.56 441 60 60

  5. Glossary API Gravity: An

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb Mar Apr MayYear Jan Feb Mar87.1CubicYear Jan Feb2.56 441 60 60

  6. Web Service Interface (API)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    OSCARS and Future Tech OSCARS Standard and Open Grid Forum OSCARS Developers Community Web Browser Interface (WBUI) Web Service Interface (API) Read More... Fasterdata IPv6...

  7. The COCONUT API Version 2.32

    E-Print Network [OSTI]

    Schichl, Hermann

    The COCONUT API Version 2.32 Reference Manual Hermann Schichl University of Vienna, Department Contents 1 COCONUT API Namespace Index 1 2 COCONUT API Hierarchical Index 1 3 COCONUT API Compound Index 8 4 COCONUT API File Index 12 5 COCONUT API Namespace Documentation 15 6 COCONUT API Class

  8. CIT 2011 2554! Facebook API

    E-Print Network [OSTI]

    Runapongsa, Kanda

    ! ! ! ! ! ! ! ! ! CIT 2011 2554! ! 1 #12; 2 #12; 3 #12; Facebook API/3) ! 24 #12; (1/2) ! 25 #12; (2/2) ! 26 #12; Facebook Query Language (FQL) FQL SQL FQL to Facebook 8th IEEE International Conference on Automatic Face & Gesture Recognition, 2008 (FG '08). H [10

  9. Coherent Averaging

    E-Print Network [OSTI]

    Julien M. E. Fraïsse; Daniel Braun

    2015-04-13

    We investigate in detail a recently introduced "coherent averaging scheme" in terms of its usefulness for achieving Heisenberg limited sensitivity in the measurement of different parameters. In the scheme, $N$ quantum probes in a product state interact with a quantum bus. Instead of measuring the probes directly and then averaging as in classical averaging, one measures the quantum bus or the entire system and tries to estimate the parameters from these measurement results. Combining analytical results from perturbation theory and an exactly solvable dephasing model with numerical simulations, we draw a detailed picture of the scaling of the best achievable sensitivity with $N$, the dependence on the initial state, the interaction strength, the part of the system measured, and the parameter under investigation.

  10. OpenEI Community - API

    Open Energy Info (EERE)

    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 QA:QA J-E-1 SECTION J APPENDIXsourceII Jump to:InformationInformationOorja Protonics JumpHome AllAPI is now

  11. OpenEI Community - APIs

    Open Energy Info (EERE)

    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 QA:QA J-E-1 SECTION J APPENDIXsourceII Jump to:InformationInformationOorja Protonics JumpHome AllAPI is

  12. Costs of Imported Crude Oil by API Gravity

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    1996 January ... 13.37 13.78 16.32 17.32 18.36 18.65 W February ... 14.23 14.73 17.14 18.38 18.10 19.58 W March ... 15.41 16.74 19.23...

  13. Costs of Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) Indexed Site

    1997 January ... 16.99 18.37 22.62 21.89 24.21 22.07 22.08 February ... 13.75 16.25 20.15 19.27 21.61 21.61 W March ... 13.39 14.96...

  14. Costs of Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb Mar Apr May Jun Jul AugAdditions1 0 0 0 0 0 1967-2014864Year

  15. Costs of Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb Mar Apr May Jun Jul AugAdditions1 0 0 0 0 0 1967-2014864Year

  16. Costs of Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb Mar Apr May Jun Jul AugAdditions1 0 0 0 0 0 1967-2014864Year

  17. Costs of Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb Mar Apr May Jun Jul AugAdditions1 0 0 0 0 0 1967-2014864Year

  18. Costs of Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb Mar Apr May Jun Jul AugAdditions1 0 0 0 0 0 1967-2014864Year

  19. Domestic Crude Oil First Purchase Prices by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb Mar Apr May Jun Jul AugAdditions1-- -- -- --WO R K I N

  20. Landed Costs of Imported Crude by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb Mar Apr 2012 2013 2014Thousand343 342 328 37056 57 61 122009

  1. Revised API Gravity ranges of EIA-182 Crude Streams

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming963 1.969 1.979 1.988 1.996 2.003 1990-2016 East Coast (PADD236Review

  2. Percentages of Total Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) 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 PageMonthly","10/2015"4,"Ames5 Tables July 1996 Energy Information Administration Office of Coal, Nuclear,DecadeYearby the Price (Percent) Year Jan Feb Mar AprPrice2009

  3. Domestic Crude Oil First Purchase Prices by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming Dry Natural GasNatural Gas UsageDiesel pricesDiesel prices top $4May-15

  4. Landed Costs of Imported Crude by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming Dry Natural GasNatural GasEIARegional energy challenges in NewNatural

  5. Landed Costs of Imported Crude by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming Dry Natural GasNatural GasEIARegional energy challenges in

  6. Percentages of Total Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming Dry Natural GasNatural GasEIARegionalMethodologyNorth093EIA-815,May-15

  7. QER- Comment of American petroleum Institute (API)

    Office of Energy Efficiency and Renewable Energy (EERE)

    Please find attached API's comments (and associated attachments) to the Department of Energy's Public Comment on the Quadrennial Energy Review [79 FR 50638, Doc. No. 2014-20114]. Please do not hesitate to contact me should you have any questions or need anything else.

  8. Api Nova Energia Srl | Open Energy Information

    Open Energy Info (EERE)

    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 QA:QA J-E-1 SECTION J APPENDIX E LISTStar Energy LLC Jump to: navigation,Summaries | Open EnergyRoadmap andApi Nova

  9. An Active Measurement API Khaled Harfoush Azer Bestavros John Byers

    E-Print Network [OSTI]

    Byers, John W.

    PeriScope An Active Measurement API Khaled Harfoush Azer Bestavros John Byers harfoush. In this paper, we present Periscope: a Linux API that enables the de#12;nition of new probing structures and inference techniques from user space through a exible interface. PeriScope requires no sup- port from

  10. CIS192 Python Programming Web Servers and Web APIs

    E-Print Network [OSTI]

    Plotkin, Joshua B.

    CIS192 Python Programming Web Servers and Web APIs Eric Kutschera University of Pennsylvania March 6, 2015 Eric Kutschera (University of Pennsylvania) CIS 192 March 6, 2015 1 / 22 #12;Outline 1 Web Servers Purpose of Web Servers Flask 2 Web APIs REST Encoding and Encryption Eric Kutschera (University

  11. Automatically Generating Refactorings to Support API Jeff H. Perkins

    E-Print Network [OSTI]

    refactorings to be automati­ cally generated for the most common types of library API changes, without any MA USA jhp@csail.mit.edu Abstract When library APIs change, client code should change in response. This approach has several benefits. It requires no change in library development practice, since programmers

  12. Automatically Generating Refactorings to Support API Jeff H. Perkins

    E-Print Network [OSTI]

    to be automati- cally generated for the most common types of library API changes, without any extra work MA USA jhp@csail.mit.edu Abstract When library APIs change, client code should change in response. This approach has several benefits. It requires no change in library development practice, since programmers

  13. Neutron resonance averaging

    SciTech Connect (OSTI)

    Chrien, R.E.

    1986-10-01

    The principles of resonance averaging as applied to neutron capture reactions are described. Several illustrations of resonance averaging to problems of nuclear structure and the distribution of radiative strength in nuclei are provided. 30 refs., 12 figs.

  14. Achronal averaged null energy condition

    SciTech Connect (OSTI)

    Graham, Noah; Olum, Ken D. [Department of Physics, Middlebury College, Middlebury, Vermont 05753 (United States) and Center for Theoretical Physics, Laboratory for Nuclear Science, and Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, Massachusetts 02155 (United States)

    2007-09-15

    The averaged null energy condition (ANEC) requires that the integral over a complete null geodesic of the stress-energy tensor projected onto the geodesic tangent vector is never negative. This condition is sufficient to prove many important theorems in general relativity, but it is violated by quantum fields in curved spacetime. However there is a weaker condition, which is free of known violations, requiring only that there is no self-consistent spacetime in semiclassical gravity in which ANEC is violated on a complete, achronal null geodesic. We indicate why such a condition might be expected to hold and show that it is sufficient to rule out closed timelike curves and wormholes connecting different asymptotically flat regions.

  15. Discovering Math APIs by Mining Unit Tests Anirudh Santhiar, Omesh Pandita

    E-Print Network [OSTI]

    Kanade, Aditya

    Discovering Math APIs by Mining Unit Tests Anirudh Santhiar, Omesh Pandita , and Aditya Kanade to discover the required APIs. In this paper, we present a technique and tool, called MathFinder, to discover APIs for mathematical computations by mining unit tests of API meth- ods. Given a math expression, Math

  16. Massive gravity from bimetric gravity

    E-Print Network [OSTI]

    Baccetti, Valentina; Visser, Matt

    2012-01-01

    We discuss the subtle relationship between so-called massive gravity (that is, gravity incorporating a non-zero graviton mass) and bimetric gravity, focussing particularly on the manner in which massive gravity may be viewed as a suitable limit of bimetric gravity. The limiting procedure is more delicate than currently appreciated, and in particular, in a cosmological context can lead to an interesting interplay between the "background" and "foreground" metrics. The fact that in bimetric theories one always has two sets of metric equations of motion, one for each metric, continues to have an effect even in the massive gravity limit. Thus, solutions of bimetric gravity in the limit of vanishing kinetic term are also solutions of massive gravity, but the contrary statement is not necessarily true.

  17. Liouville gravity from Einstein gravity

    E-Print Network [OSTI]

    D. Grumiller; R. Jackiw

    2007-12-28

    We show that Liouville gravity arises as the limit of pure Einstein gravity in 2+epsilon dimensions as epsilon goes to zero, provided Newton's constant scales with epsilon. Our procedure - spherical reduction, dualization, limit, dualizing back - passes several consistency tests: geometric properties, interactions with matter and the Bekenstein-Hawking entropy are as expected from Einstein gravity.

  18. X:\\L6046\\Data_Publication\\Pma\\current\\ventura\\pma.vp

    U.S. Energy Information Administration (EIA) Indexed Site

    States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 - by API gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 - for...

  19. Restricting information flow in security APIs via typing 

    E-Print Network [OSTI]

    Keighren, Gavin

    2014-06-27

    Security APIs are designed to enable the storage and processing of confidential data without that data becoming known to individuals who are not permitted to obtain it, and are central to the operation of Automated Teller ...

  20. Lab 6: Java API CSC1051 1/4

    E-Print Network [OSTI]

    Papalaskari, Mary-Angela

    Lab 6: Java API CSC1051 1/4 Java derives much of its power from the many classes already defined in the Java API. But how are we ever to learn and use these classes if we don't know about them? Any text on Java can only begin to cover these classes and the methods defined in them. For a complete listing

  1. Average Angular Velocity

    E-Print Network [OSTI]

    H. Essen

    2004-01-28

    This paper addresses the problem of the separation of rotational and internal motion. It introduces the concept of average angular velocity as the moment of inertia weighted average of particle angular velocities. It extends and elucidates the concept of Jellinek and Li (1989) of separation of the energy of overall rotation in an arbitrary (non-linear) $N$-particle system. It generalizes the so called Koenig's theorem on the two parts of the kinetic energy (center of mass plus internal) to three parts: center of mass, rotational, plus the remaining internal energy relative to an optimally translating and rotating frame.

  2. Einstein Gravity from Conformal Gravity

    E-Print Network [OSTI]

    Juan Maldacena

    2011-06-09

    We show that that four dimensional conformal gravity plus a simple Neumann boundary condition can be used to get the semiclassical (or tree level) wavefunction of the universe of four dimensional asymptotically de-Sitter or Euclidean anti-de Sitter spacetimes. This simple Neumann boundary condition selects the Einstein solution out of the more numerous solutions of conformal gravity. It thus removes the ghosts of conformal gravity from this computation. In the case of a five dimensional pure gravity theory with a positive cosmological constant we show that the late time superhorizon tree level probability measure, $|\\Psi [ g ]|^2$, for its four dimensional spatial slices is given by the action of Euclidean four dimensional conformal gravity.

  3. V-142: Oracle Java Reflection API Flaw Lets Remote Users Execute...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    2: Oracle Java Reflection API Flaw Lets Remote Users Execute Arbitrary Code V-142: Oracle Java Reflection API Flaw Lets Remote Users Execute Arbitrary Code April 25, 2013 - 12:14am...

  4. Help:US Utility Rate Database API Tutorial | Open Energy Information

    Open Energy Info (EERE)

    with OpenEI API Requests to the OpenEI API can be made in the address bar of your internet search engine. The following is the base of the "request url" that allows a user to...

  5. Gravity brake

    DOE Patents [OSTI]

    Lujan, Richard E. (Santa Fe, NM)

    2001-01-01

    A mechanical gravity brake that prevents hoisted loads within a shaft from free-falling when a loss of hoisting force occurs. A loss of hoist lifting force may occur in a number of situations, for example if a hoist cable were to break, the brakes were to fail on a winch, or the hoist mechanism itself were to fail. Under normal hoisting conditions, the gravity brake of the invention is subject to an upward lifting force from the hoist and a downward pulling force from a suspended load. If the lifting force should suddenly cease, the loss of differential forces on the gravity brake in free-fall is translated to extend a set of brakes against the walls of the shaft to stop the free fall descent of the gravity brake and attached load.

  6. FLAG@lab: An M-script API for Linear Algebra Operations on Graphics Processors

    E-Print Network [OSTI]

    Batory, Don

    FLAG@lab: An M-script API for Linear Algebra Operations on Graphics Processors Sergio Barrachina interfaces (APIs) to use a graphics processing unit (GPU) as a co-processor for dense linear algebra operations. Combined with an extension of the FLAME API and an implementation on top of NVIDIA CUBLAS

  7. The COCONUT API Version 4.0.0005

    E-Print Network [OSTI]

    Schichl, Hermann

    The COCONUT API Version 4.0.0005 Reference Manual Hermann Schichl University of Vienna Faculty Documentation 223 11 File Documentation 1971 1 Introduction The COCONUT environment is a modular solver::coco::full_node::get_database () const This method needs to be replaced, once the COCONUT environment really gets distributed. Member

  8. Privacy Issues of the W3C Geolocation API

    E-Print Network [OSTI]

    Doty, Nick; Mulligan, Deirdre K.; Wilde, Erik

    2010-01-01

    APIs for HTML and XHTML. World Wide Web Consortium, WorkingInstead, web sites are expected to use the HTML content ofweb sites to proactively 9 https://datatracker.ietf.org/liaison/486/ 10 http://lists.w3.org/Archives/Public/public-geolocation/2009Mar/0131.html

  9. Is nonrelativistic gravity possible?

    SciTech Connect (OSTI)

    Kocharyan, A. A.

    2009-07-15

    We study nonrelativistic gravity using the Hamiltonian formalism. For the dynamics of general relativity (relativistic gravity) the formalism is well known and called the Arnowitt-Deser-Misner (ADM) formalism. We show that if the lapse function is constrained correctly, then nonrelativistic gravity is described by a consistent Hamiltonian system. Surprisingly, nonrelativistic gravity can have solutions identical to relativistic gravity ones. In particular, (anti-)de Sitter black holes of Einstein gravity and IR limit of Horava gravity are locally identical.

  10. Stochastic Gravity

    E-Print Network [OSTI]

    B. L. Hu

    1999-02-22

    We give a summary of the status of current research in stochastic semiclassical gravity and suggest directions for further investigations. This theory generalizes the semiclassical Einstein equation to an Einstein-Langevin equation with a stochastic source term arising from the fluctuations of the energy-momentum tensor of quantum fields. We mention recent efforts in applying this theory to the study of black hole fluctuations and backreaction problems, linear response of hot flat space, and structure formation in inflationary cosmology. To explore the physical meaning and implications of this stochastic regime in relation to both classical and quantum gravity, we find it useful to take the view that semiclassical gravity is mesoscopic physics and that general relativity is the hydrodynamic limit of certain spacetime quantum substructures. Three basic issues - stochasticity, collectivity, correlations- and three processes - dissipation, fluctuations, decoherence- underscore the transformation from quantum micro structure and interaction to the emergence of classical macro structure and dynamics. We discuss ways to probe into the high energy activity from below and make two suggestions: via effective field theory and the correlation hierarchy. We discuss how stochastic behavior at low energy in an effective theory and how correlation noise associated with coarse-grained higher correlation functions in an interacting quantum field could carry nontrivial information about the high energy sector. Finally we describe processes deemed important at the Planck scale, including tunneling and pair creation, wave scattering in random geometry, growth of fluctuations and forms, Planck scale resonance states, and spacetime foams.

  11. ,"Domestic Crude Oil First Purchase Prices by API Gravity"

    U.S. Energy Information Administration (EIA) 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 Data Center Home Page| Open Energy Informationmonthly gasoline price to fall to $3.43U.S.longec 188 U.S.1 HomeRegional37Annual* j o n

  12. Table 23. Domestic Crude Oil First Purchase Prices by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    1996 January ... 13.80 15.60 12.16 17.04 16.97 17.65 February ... 14.16 15.49 12.78 16.84 16.94 17.60 March ......

  13. Table 23. Domestic Crude Oil First Purchase Prices by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    1997 January ... 19.26 21.50 18.87 23.25 23.40 24.07 February ... 16.63 18.34 17.74 20.36 20.62 21.19 March ......

  14. Table 28. Percentages of Total Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    1996 January ... 4.15 22.60 17.85 28.54 23.19 2.19 1.48 February ... 4.52 22.26 14.69 28.79 24.96 3.51 1.27 March ... 3.79 19.54 19.77...

  15. Table 28. Percentages of Total Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    1997 January ... 4.81 21.56 12.96 34.96 21.61 2.76 1.34 February ... 4.66 22.18 15.45 29.96 24.56 2.33 0.86 March ... 5.24 21.60 12.11...

  16. Table 27. Landed Costs of Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    1996 January ... 14.41 14.81 17.62 18.12 18.80 19.22 18.47 February ... 15.29 15.52 17.66 18.86 18.80 20.03 19.74 March ... 16.57 17.52...

  17. Table 27. Landed Costs of Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) Indexed Site

    1997 January ... 18.57 19.34 23.73 22.13 24.80 23.89 23.89 February ... 14.79 17.00 21.18 19.69 22.81 22.74 24.44 March ... 14.56 16.06...

  18. Table 23. Domestic Crude Oil First Purchase Prices by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 January33

  19. Table 23. Domestic Crude Oil First Purchase Prices by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 January33

  20. Table 23. Domestic Crude Oil First Purchase Prices by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 January33

  1. Table 23. Domestic Crude Oil First Purchase Prices by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 January33

  2. Table 23. Domestic Crude Oil First Purchase Prices by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 January33

  3. Table 27. Landed Costs of Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 1994 1995

  4. Table 27. Landed Costs of Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 1994 1995

  5. Table 27. Landed Costs of Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 1994 1995

  6. Table 27. Landed Costs of Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 1994 1995

  7. Table 27. Landed Costs of Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 1994 1995

  8. Table 28. Percentages of Total Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 1994 1995

  9. Table 28. Percentages of Total Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 1994 1995

  10. Table 28. Percentages of Total Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 1994 1995

  11. Table 28. Percentages of Total Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 1994 1995

  12. Table 28. Percentages of Total Imported Crude Oil by API Gravity

    U.S. Energy Information Administration (EIA) 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: AlternativeMonthly","10/2015"Monthly","10/2015" ,"Release7CubicthroughtheSeptember 24, 20145,137 4,9743Number63 1993 1994 1995

  13. F.O.B. Costs of Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb Mar Apr May Jun2003 DetailedThousand Cubic2009 2010 2011 2012

  14. F.O.B. Costs of Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming Dry Natural GasNatural GasEIA lowers 2015 U.S.4LycomingReview,xx/xx/xxxx

  15. F.O.B. Costs of Imported Crude Oil by API Gravity

    Gasoline and Diesel Fuel Update (EIA)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming Dry Natural GasNatural GasEIA lowers 2015

  16. APIs for Online Energy Saving Tools: Home Energy Saver and EnergyIQ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    KB) Technology Marketing Summary Berkeley Lab is offering direct access to Application Programming Interfaces (APIs) for two popular, proven energy saving online tools: Home...

  17. TORSION AND QUANTUM GRAVITY

    E-Print Network [OSTI]

    Hanson, Andrew J.

    2011-01-01

    more restrictive context of Einstein's theory of gravity.6782 TORSION AND QUANTUM GRAVITY Andrevr J, Him son Lawrencetorsion in conventional gravity cou~d in fact be dynamicaL A

  18. Intrusive gravity currents

    E-Print Network [OSTI]

    Hang, Alice Thanh

    2009-01-01

    The front speed of intrusive gravity currents. J. FluidP.F. Linden. Intrusive gravity currents. J. Fluid Mechanics,of mesoscale variability of gravity waves. Part II: Frontal,

  19. Spacetime Averaged Null Energy Condition

    E-Print Network [OSTI]

    Douglas Urban; Ken D. Olum

    2010-06-13

    The averaged null energy condition has known violations for quantum fields in curved space, even if one considers only achronal geodesics. Many such examples involve rapid variation in the stress-energy tensor in the vicinity of the geodesic under consideration, giving rise to the possibility that averaging in additional dimensions would yield a principle universally obeyed by quantum fields. However, after discussing various procedures for additional averaging, including integrating over all dimensions of the manifold, we give a class of examples that violate any such averaged condition.

  20. Spacetime averaged null energy condition

    SciTech Connect (OSTI)

    Urban, Douglas; Olum, Ken D.

    2010-06-15

    The averaged null energy condition has known violations for quantum fields in curved space, even when one considers only achronal geodesics. Many such examples involve rapid variation in the stress-energy tensor in the vicinity of the geodesic under consideration, giving rise to the possibility that averaging in additional dimensions would yield a principle universally obeyed by quantum fields. However, after discussing various procedures for additional averaging, including integrating over all dimensions of the manifold, we give here a class of examples that violate any such averaged condition.

  1. OpenEI API listing | OpenEI Community

    Open Energy Info (EERE)

    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 QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to:Newberg, Oregon:OGE EnergyOklahoma: EnergyOpenOpenEI API listing Home

  2. OpenEI API. Implementation help | OpenEI Community

    Open Energy Info (EERE)

    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 QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to:Newberg, Oregon:OGE EnergyOklahoma: EnergyOpenOpenEI API listing

  3. Energy API and dataset overview | OpenEI Community

    Open Energy Info (EERE)

    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 QA:QA J-E-1 SECTION J APPENDIX ECoopButtePowerEdisto Electric Coop, Inc JumpElko,Servizi Engineering SpA EEnergy API

  4. Towards Automatically Estimating Porting Effort Between Web Service APIs Hiranya Jayathilaka, Chandra Krintz, Rich Wolski

    E-Print Network [OSTI]

    Bigelow, Stephen

    Towards Automatically Estimating Porting Effort Between Web Service APIs Hiranya Jayathilaka to another. Keywords-Web APIs; Porting effort; Semantic similarity I. INTRODUCTION Web services are used in their applications (or, indeed, as part of other web services). Building applica- tions from curated web services

  5. An Active Internet Probing and Measurement API Khaled Harfoush Azer Bestavros John Byers

    E-Print Network [OSTI]

    1 PeriScope An Active Internet Probing and Measurement API Khaled Harfoush Azer Bestavros John- der to infer speci#12;c metrics of interest. In this paper, we present Periscope: a Linux API a exible interface. PeriScope requires no sup- port from clients beyond the ability to respond to ICMP ECHO

  6. Data Management in the GridRPC GridRPC Data Management API

    E-Print Network [OSTI]

    Caniou, Yves

    Data Management in the GridRPC Issues Conclusion GridRPC Data Management API Implementations, Le Mahec, Nakada GridRPC DM API: Implem. and Interop. Issues (1/13) #12;Data Management in the GridRPC Issues Conclusion Goal GridRPC DM types: Reminder 1 Data Management in the GridRPC Goal GridRPC DM types

  7. On the Effectiveness of API-Level Access Control Using Bytecode Rewriting in Android

    E-Print Network [OSTI]

    Du, Wenliang "Kevin"

    On the Effectiveness of API-Level Access Control Using Bytecode Rewriting in Android Hao Hao, Vicky, New York, USA {hahao,vsingh02,wedu}@syr.edu ABSTRACT Bytecode rewriting on Android applications has the effectiveness of API-level access control using bytecode rewriting on Android Operating System. In our

  8. Averaging Hypotheses in Newtonian Cosmology

    E-Print Network [OSTI]

    T. Buchert

    1995-12-20

    Average properties of general inhomogeneous cosmological models are discussed in the Newtonian framework. It is shown under which circumstances the average flow reduces to a member of the standard Friedmann--Lema\\^\\i tre cosmologies. Possible choices of global boundary conditions of inhomogeneous cosmologies as well as consequences for the interpretation of cosmological parameters are put into perspective.

  9. Chiral Gravity, Log Gravity and Extremal CFT

    E-Print Network [OSTI]

    Alexander Maloney; Wei Song; Andrew Strominger

    2009-03-26

    We show that the linearization of all exact solutions of classical chiral gravity around the AdS3 vacuum have positive energy. Non-chiral and negative-energy solutions of the linearized equations are infrared divergent at second order, and so are removed from the spectrum. In other words, chirality is confined and the equations of motion have linearization instabilities. We prove that the only stationary, axially symmetric solutions of chiral gravity are BTZ black holes, which have positive energy. It is further shown that classical log gravity-- the theory with logarithmically relaxed boundary conditions --has finite asymptotic symmetry generators but is not chiral and hence may be dual at the quantum level to a logarithmic CFT. Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We normally evaluate the Euclidean sum over geometries of chiral gravity and show that it gives precisely the holomorphic extremal CFT partition function. The modular invariance and integrality of the expansion coefficients of this partition function are consistent with the existence of an exact quantum theory of chiral gravity. We argue that the problem of quantizing chiral gravity is the holographic dual of the problem of constructing an extremal CFT, while quantizing log gravity is dual to the problem of constructing a logarithmic extremal CFT.

  10. Towards noncommutative gravity

    E-Print Network [OSTI]

    D. V. Vassilevich

    2009-02-17

    In this short article accessible for non-experts I discuss possible ways of constructing a non-commutative gravity paying special attention to possibilities of realizing the full diffeomorphism symmetry and to relations with 2D gravities.

  11. Is gravity entropic force?

    E-Print Network [OSTI]

    Rong-Jia Yang

    2014-09-11

    If we assume that the source of thermodynamic system, $\\rho$ and $p$, are also the source of gravity, thermal quantities, such as entropy, temperature, and chemical potential, can induce effects of gravity, or gravity can induce thermal effects. We find only for systems with constant temperature and zero chemical potential, gravity can be seen as an entropic force. The case for Newtonian approximation is discussed.

  12. Motion in Quantum Gravity

    E-Print Network [OSTI]

    Karim Noui

    2010-03-31

    We tackle the question of motion in Quantum Gravity: what does motion mean at the Planck scale? Although we are still far from a complete answer we consider here a toy model in which the problem can be formulated and resolved precisely. The setting of the toy model is three dimensional Euclidean gravity. Before studying the model in detail, we argue that Loop Quantum Gravity may provide a very useful approach when discussing the question of motion in Quantum Gravity.

  13. Terrestrial Gravity Fluctuations

    E-Print Network [OSTI]

    Jan Harms

    2015-07-21

    The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our understanding of terrestrial gravity fluctuations will have great impact on the future development of GW detectors and high-precision gravimetry in general, and many open questions need to be answered still as emphasized in this article.

  14. VisionGL: Towards an API for Integrating Vision and Graphics Gregor Miller and Sidney Fels

    E-Print Network [OSTI]

    British Columbia, University of

    VisionGL: Towards an API for Integrating Vision and Graphics Gregor Miller and Sidney Fels Human) and per- formance/appearance capture. Recently we introduced OpenVL [Miller and Fels 2013], an abstraction

  15. Stephen Hawking Quantum Gravity

    E-Print Network [OSTI]

    Visser, Matt

    Stephen Hawking and Quantum Gravity Matt Visser Physics Department Washington University Saint Louis USA Science Saturdays 4 Nov 2000 #12; Stephen Hawking and Quantum Gravity Abstract: Through research, Stephen Hawking has captured a place in the popular imagina- tion. Quantum gravity in its various

  16. Quantum Physics Einstein's Gravity

    E-Print Network [OSTI]

    Visser, Matt

    Quantum Physics confronts Einstein's Gravity Matt Visser Physics Department Washington University Saint Louis USA Science Saturdays 13 October 2001 #12; Quantum Physics confronts Einstein's Gravity and with Einstein's theory of gravity (the general relativity) is still the single biggest theoretical problem

  17. Quantum Averages of Weak Values

    E-Print Network [OSTI]

    Yakir Aharonov; Alonso Botero

    2005-08-23

    We re-examine the status of the weak value of a quantum mechanical observable as an objective physical concept, addressing its physical interpretation and general domain of applicability. We show that the weak value can be regarded as a \\emph{definite} mechanical effect on a measuring probe specifically designed to minimize the back-reaction on the measured system. We then present a new framework for general measurement conditions (where the back-reaction on the system may not be negligible) in which the measurement outcomes can still be interpreted as \\emph{quantum averages of weak values}. We show that in the classical limit, there is a direct correspondence between quantum averages of weak values and posterior expectation values of classical dynamical properties according to the classical inference framework.

  18. A RESTful API for accessing microbial community data for MG-RAST

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wilke, Andreas; Bischof, Jared; Harrison, Travis; Brettin, Tom; D'Souza, Mark; Gerlach, Wolfgang; Matthews, Hunter; Paczian, Tobias; Wilkening, Jared; Glass, Elizabeth M.; et al

    2015-01-08

    Metagenomic sequencing has produced significant amounts of data in recent years. For example, as of summer 2013, MGRAST has been used to annotate over 110,000 data sets totaling over 43 Terabases. With metagenomic sequencing finding even wider adoption in the scientific community, the existing web-based analysis tools and infrastructure in MG-RAST provide limited capability for data retrieval and analysis, such as comparative analysis between multiple data sets. Moreover, although the system provides many analysis tools, it is not comprehensive. By opening MG-RAST up via a web services API (application programmers interface) we have greatly expanded access to MG-RAST data, asmore »well as provided a mechanism for the use of third-party analysis tools with MG-RAST data. This RESTful API makes all data and data objects created by the MG-RAST pipeline accessible as JSON objects. As part of the DOE Systems Biology Knowledgebase project (KBase, http:// kbase.us) we have implemented a web services API for MG-RAST. This API complements the existing MG-RAST web interface and constitutes the basis of KBase’s microbial community capabilities. In addition, the API exposes a comprehensive collection of data to programmers. This API, which uses a RESTful (Representational State Transfer) implementation, is compatible with most programming environments and should be easy to use for end users and third parties. It provides comprehensive access to sequence data, quality control results, annotations, and many other data types. Where feasible, we have used standards to expose data and metadata. Code examples are provided in a number of languages both to show the versatility of the API and to provide a starting point for users. We present an API that exposes the data in MG-RAST for consumption by our users, greatly enhancing the utility of the MG-RAST service.« less

  19. Quantization of Emergent Gravity

    E-Print Network [OSTI]

    Hyun Seok Yang

    2014-12-24

    Emergent gravity is based on a novel form of the equivalence principle known as the Darboux theorem or the Moser lemma in symplectic geometry stating that the electromagnetic force can always be eliminated by a local coordinate transformation as far as spacetime admits a symplectic structure, in other words, a microscopic spacetime becomes noncommutative (NC). If gravity emerges from U(1) gauge theory on NC spacetime, this picture of emergent gravity suggests a completely new quantization scheme where quantum gravity is defined by quantizing spacetime itself, leading to a dynamical NC spacetime. Therefore the quantization of emergent gravity is radically different from the conventional approach trying to quantize a phase space of metric fields. This approach for quantum gravity allows a background independent formulation where spacetime as well as matter fields is equally emergent from a universal vacuum of quantum gravity.

  20. Average-Atom Thomson Scattering

    E-Print Network [OSTI]

    Johnson, Walter R.

    -Atom Approximation W. R. Johnson, Notre Dame J. Nilsen & K. T. Cheng, LLNL The cross section for Thomson scattering Average-Atom Model Divide plasma into WS cells with a nucleus and Z electrons p2 2 - Z r + V a(r) = a a(r) V(r) = VKS(n(r), r) n(r) = nb(r) + nc(r) 4r2nb(r) = nl 2(2l+1) 1+exp[( nl -µ)/kBT] Pnl(r)2 Z = r

  1. Dark gravity and cosmology

    E-Print Network [OSTI]

    F. Henry-Couannier; A. Tilquin; C. Tao; A. Ealet

    2007-10-24

    The previous version of this article was a first attempt to confront the Dark Gravity theory to cosmological data. However, more recent developments lead to the conclusion that the cosmological principle is probably not valid in Dark Gravity so that this kind of analysis is at best very premature. A more recent and living review of the Dark Gravity theory can be found in gr-qc/0610079

  2. Is Gravity an Interaction?

    E-Print Network [OSTI]

    Felix M. Lev

    2010-05-16

    We consider a possibility that gravity is not an interaction but a manifestation of a symmetry based on a Galois field.

  3. Emergent gravity requires kinematic nonlocality

    E-Print Network [OSTI]

    Marolf, D

    2015-01-01

    Saueressig, Quantum Einstein Gravity, New J.Phys. 14 (2012)T. Matsuki, and H. Terazawa, Gravity and Electromagnetism asat a lattice formulation of gravity, . http://cds.cern.ch/

  4. Quantum gravity on the lattice

    E-Print Network [OSTI]

    Hamber, Herbert W.

    2009-01-01

    the Conference Quantum Gravity: Challenges and Perspectives.divergences in quantum gravity. In: Hawking, S.W. , Israel,f ) V n?1 ( f ) = Quantum gravity on the lattice Similarly,

  5. A. Peer-reviewed publications 40. Forsgren E, Fries I, de Miranda JR (2012) Adult honey bees (Apis mellifera) with deformed wings discovered in

    E-Print Network [OSTI]

    2012-01-01

    (2011) Deformed wing virus and drone mating in the honey bee (Apis mellifera): implications for sexual, Bergoin M (2006) Localization of deformed wing virus infection in queen and drone Apis mellifera L.. Virol

  6. Mechanical Characteristics of Submerged Arc Weldment in API Gas Pipeline Steel of Grade X65

    SciTech Connect (OSTI)

    Hashemi, S. H.; Mohammadyani, D.

    2011-01-17

    The mechanical properties of submerged arc weldment (SAW) in gas transportation pipeline steel of grade API X65 (65 ksi yield strength) were investigated. This steel is produced by thermo mechanical control rolled (TMC), and is largely used in Iran gas piping systems and networks. The results from laboratory study on three different regions; i.e. base metal (BM), fusion zone (FZ) and heat affected zone (HAZ) were used to compare weldment mechanical characteristics with those specified by API 5L (revision 2004) standard code. Different laboratory experiments were conducted on test specimens taken from 48 inch outside diameter and 14.3 mm wall thickness gas pipeline. The test results showed a gradient of microstructure and Vickers hardness data from the centerline of FZ towards the unaffected MB. Similarly, lower Charpy absorbed energy (compared to BM) was observed in the FZ impact specimens. Despite this, the API specifications were fulfilled in three tested zones, ensuring pipeline structural integrity under working conditions.

  7. Topics in Nonsupersymmetric Scattering Amplitudes in Gauge and Gravity Theories

    E-Print Network [OSTI]

    Nohle, Joshua David

    2015-01-01

    Gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Ultraviolet Properties of Gravity . . . . . . .Kinematics Duality and Gravity as a Double Copy of Yang-

  8. Probability around the Quantum Gravity. Part 1: Planar Pure Gravity

    E-Print Network [OSTI]

    Probability around the Quantum Gravity. Part 1: Planar Pure Gravity V.A.Malyshev \\Lambda September 17, 1998 Abstract In this paper we study stochastic dynamics which leaves quantum gravity equilibrium science and biology. At the same time the paper can serve an intro­ duction to quantum gravity

  9. Gravity in Gauge Mediation

    E-Print Network [OSTI]

    Zygmunt Lalak; Stefan Pokorski; Krzysztof Turzynski

    2008-08-18

    We investigate O'Raifeartaigh-type models for F-term supersymmetry breaking in gauge mediation scenarios in the presence of gravity. It is pointed out that the vacuum structure of those models is such that in metastable vacua gravity mediation contribution to scalar masses is always suppressed to the level below 1 percent, almost sufficient for avoiding FCNC problem. Close to that limit, gravitino mass can be in the range 10-100 GeV, opening several interesting possibilities for gauge mediation models, including Giudice-Masiero mechanism for mu and Bmu generation. Gravity sector can include stabilized moduli.

  10. Spectral averaging techniques for Jacobi matrices

    E-Print Network [OSTI]

    Rafael del Rio; Carmen Martinez; Hermann Schulz-Baldes

    2008-02-20

    Spectral averaging techniques for one-dimensional discrete Schroedinger operators are revisited and extended. In particular, simultaneous averaging over several parameters is discussed. Special focus is put on proving lower bounds on the density of the averaged spectral measures. These Wegner type estimates are used to analyze stability properties for the spectral types of Jacobi matrices under local perturbations.

  11. THE FINE STRUCTURE OF THE WAX GLAND OF THE HONEY BEE (APIS MELLIFERA L.)

    E-Print Network [OSTI]

    Boyer, Edmond

    THE FINE STRUCTURE OF THE WAX GLAND OF THE HONEY BEE (APIS MELLIFERA L.) Malcolin T. SANFORD Alfred An electron microscopic study was initiated to elucidate the ultrastructure of the wax gland in an actively wax secreting worker honey bee. The investigation showed that the cuticle is penetrated by bundles

  12. Parallelizing Compiler Framework and API for Power Reduction and Software Productivity of

    E-Print Network [OSTI]

    Kasahara, Hironori

    Parallelizing Compiler Framework and API for Power Reduction and Software Productivity of Real, this paper proposes a compilation framework which bridges a gap between programmers and heterogeneous multicores. In particular, this paper describes the compilation framework based on OSCAR com- piler

  13. OSCAR Parallelizing Compiler and API for Real-time Low Power Heterogeneous Multicores

    E-Print Network [OSTI]

    Kasahara, Hironori

    OSCAR Parallelizing Compiler and API for Real-time Low Power Heterogeneous Multicores Akihiro, this paper describes OSCAR par- allelizing compiler which bridges a gap between programmers and hetero- geneous multicores. In particular, this paper describes the compilation framework based on OSCAR compiler

  14. An API for Manipulating Matrices Stored by Blocks Tze Meng Low

    E-Print Network [OSTI]

    Batory, Don

    contracts ACI-0305163 and CCF-0342369 and an equipment donation from Hewlett-Packard. 1 #12;The simple algorithms that perform operations on such matrices. Notice that we are not proposing a standard for the API and resulting library. Much will need to be learned about this new approach to coding before standardization

  15. Adding Meaning to Facebook Microposts via a Mash-up API and Tracking Its Data Provenance

    E-Print Network [OSTI]

    Cortes, Corinna

    Adding Meaning to Facebook Microposts via a Mash-up API and Tracking Its Data Provenance Thomas--The social networking website Facebook offers to its users a feature called "status updates" (or just "status. INTRODUCTION According to official Facebook statistics [7], the social networking website has more than 500

  16. Deformed wing virus and drone mating flights in the honey bee (Apis mellifera): implications for sexual

    E-Print Network [OSTI]

    Paxton, Robert

    Deformed wing virus and drone mating flights in the honey bee (Apis mellifera): implications clear evidence for the occurrence of high DWV titres in the endophallus of sexually mature drones collected from drone congregation areas (DCAs). Furthermore, the endophallus DWV titres of drones collected

  17. How Do API Changes Trigger Stack Overflow Discussions? A Study on the Android SDK

    E-Print Network [OSTI]

    Poshyvanyk, Denys

    How Do API Changes Trigger Stack Overflow Discussions? A Study on the Android SDK Mario LinaresOverflow highlights an increasing interest of software developers in mobile programming. For the Android platform, 213,836 questions were tagged with Android-related labels in StackOverflow between July 2008 and August 2012

  18. DroidAPIMiner: Mining API-Level Features for Robust Malware Detection in Android

    E-Print Network [OSTI]

    Du, Wenliang "Kevin"

    DroidAPIMiner: Mining API-Level Features for Robust Malware Detection in Android Yousra Aafer, USA {yaafer, wedu, heyin}@syr.edu Abstract. The increasing popularity of Android apps makes them enough. In this paper, we aim to mitigate Android malware installation through providing robust

  19. Architecture and Measured Characteristics of a Cloud Based Internet of Things API

    E-Print Network [OSTI]

    Architecture and Measured Characteristics of a Cloud Based Internet of Things API Geoffrey C. Fox Indiana University, Bloomington IN 47408 USA rdhartma@indiana.edu ABSTRACT The Internet of Things (Io systems [2,3]. This is the vision of the Internet of Things. We present a cloud-compatible open source

  20. Why gravity is fundamental

    E-Print Network [OSTI]

    Shan Gao

    2011-07-16

    It is argued that the existence of a minimum size of spacetime may imply the fundamental existence of gravity as a geometric property of spacetime described by general relativity.

  1. Muons, gravity and time

    E-Print Network [OSTI]

    Francis J. M. Farley

    2015-08-14

    In the muon storage rings the muons are subject to a very large radial acceleration. The equivalence principle implies a large gravity force. It has no effect on the muon lifetime.

  2. Exercise in artificial gravity

    E-Print Network [OSTI]

    Edmonds, Jessica Leigh

    2005-01-01

    Artificial gravity provided by short radius centrifugation is considered a promising countermeasure to the deleterious physiological effects of microgravity during long-duration space flight. We investigated the feasibility ...

  3. Gravity-driven intrusions in stratified fluids

    E-Print Network [OSTI]

    Maurer, Benjamin Dudley

    2011-01-01

    5.5.1 Five interleaving interfacial gravity currents 5.5.2Ten interleaving interfacial gravity currents . 5.6partial- depth intrusive gravity currents,” Atmosphere -

  4. Dynamic Multiscale Averaging (DMA) of Turbulent Flow

    SciTech Connect (OSTI)

    Richard W. Johnson

    2012-09-01

    A new approach called dynamic multiscale averaging (DMA) for computing the effects of turbulent flow is described. The new method encompasses multiple applications of temporal and spatial averaging, that is, multiscale operations. Initially, a direct numerical simulation (DNS) is performed for a relatively short time; it is envisioned that this short time should be long enough to capture several fluctuating time periods of the smallest scales. The flow field variables are subject to running time averaging during the DNS. After the relatively short time, the time-averaged variables are volume averaged onto a coarser grid. Both time and volume averaging of the describing equations generate correlations in the averaged equations. These correlations are computed from the flow field and added as source terms to the computation on the next coarser mesh. They represent coupling between the two adjacent scales. Since they are computed directly from first principles, there is no modeling involved. However, there is approximation involved in the coupling correlations as the flow field has been computed for only a relatively short time. After the time and spatial averaging operations are applied at a given stage, new computations are performed on the next coarser mesh using a larger time step. The process continues until the coarsest scale needed is reached. New correlations are created for each averaging procedure. The number of averaging operations needed is expected to be problem dependent. The new DMA approach is applied to a relatively low Reynolds number flow in a square duct segment. Time-averaged stream-wise velocity and vorticity contours from the DMA approach appear to be very similar to a full DNS for a similar flow reported in the literature. Expected symmetry for the final results is produced for the DMA method. The results obtained indicate that DMA holds significant potential in being able to accurately compute turbulent flow without modeling for practical engineering applications.

  5. On the no-gravity limit of gravity

    E-Print Network [OSTI]

    J. Kowalski-Glikman; M. Szczachor

    2012-12-21

    We argue that Relative Locality may arise in the no gravity $G\\rightarrow0$ limit of gravity. In this limit gravity becomes a topological field theory of the BF type that, after coupling to particles, may effectively deform its dynamics. We briefly discuss another no gravity limit with a self dual ground state as well as the topological ultra strong $G\\rightarrow\\infty$ one.

  6. MESOSCALE AVERAGING OF NUCLEATION AND GROWTH MODELS

    E-Print Network [OSTI]

    Ferguson, Thomas S.

    MESOSCALE AVERAGING OF NUCLEATION AND GROWTH MODELS MARTIN BURGER , VINCENZO CAPASSO , AND LIVIO-Kolmogorov relations for the degree of crystallinity. By relating the computation of expected values to mesoscale averaging, we obtain a suitable description of the process at the mesoscale. We show how the variance

  7. Optimal Average Cost Manufacturing Flow Controllers

    E-Print Network [OSTI]

    Veatch, Michael H.

    policy the differ- ential cost is C1 on attractive control switching boundaries. Index Terms Average costOptimal Average Cost Manufacturing Flow Controllers: Convexity and Differentiability Michael H and differentiability of the differential cost function are investigated. It is proven that under an optimal control

  8. Averages in vector spaces over finite fields 

    E-Print Network [OSTI]

    Wright J.; Carbery A.; Stones B.

    2008-01-01

    We study the analogues of the problems of averages and maximal averages over a surface in R-n when the euclidean structure is replaced by that of a vector space over a finite field, and obtain optimal results in a number ...

  9. Gauge/Gravity Duality

    ScienceCinema (OSTI)

    Polchinski, Joseph [Kavli Institute for Theoretical Physics

    2010-09-01

    Gauge theories, which describe the particle interactions, are well understood, while quantum gravity leads to many puzzles. Remarkably, in recent years we have learned that these are actually dual, the same system written in different variables. On the one hand, this provides our most precise description of quantum gravity, resolves some long-standing paradoxes, and points to new principles. On the other, it gives a new perspective on strong interactions, with surprising connections to other areas of physics. I describe these ideas, and discuss current and future directions.

  10. Introduction Basics of gravity theory

    E-Print Network [OSTI]

    Visser, Matt

    Introduction Basics of gravity theory Actions and Field Equations Phenomenology Discussion;Introduction Basics of gravity theory Actions and Field Equations Phenomenology Discussion and Conclusions Victoria U of Wellington - Feb 2nd 2009 #12;Introduction Basics of gravity theory Actions and Field

  11. Loop quantum gravity and observations

    E-Print Network [OSTI]

    A. Barrau; J. Grain

    2015-10-28

    Quantum gravity has long been thought to be completely decoupled from experiments or observations. Although it is true that smoking guns are still missing, there are now serious hopes that quantum gravity phenomena might be tested. We review here some possible ways to observe loop quantum gravity effects either in the framework of cosmology or in astroparticle physics.

  12. Even-dimensional topological gravity from Chern-Simons gravity

    E-Print Network [OSTI]

    Nelson Merino; Alfredo Perez; Patricio Salgado

    2009-10-08

    It is shown that the topological action for gravity in 2n-dimensions can be obtained from the 2n+1-dimensional Chern-Simons gravity genuinely invariant under the Poincare group. The 2n-dimensional topological gravity is described by the dynamics of the boundary of a 2n+1-dimensional Chern-Simons gravity theory with suitable boundary conditions. The field $\\phi^{a}$, which is necessary to construct this type of topological gravity in even dimensions, is identified with the coset field associated with the non-linear realizations of the Poincare group ISO(d-1,1).

  13. From Classical To Quantum Gravity: Introduction to Loop Quantum Gravity

    E-Print Network [OSTI]

    Kristina Giesel; Hanno Sahlmann

    2013-01-02

    We present an introduction to the canonical quantization of gravity performed in loop quantum gravity, based on lectures held at the 3rd quantum geometry and quantum gravity school in Zakopane in 2011. A special feature of this introduction is the inclusion of new proposals for coupling matter to gravity that can be used to deparametrize the theory, thus making its dynamics more tractable. The classical and quantum aspects of these new proposals are explained alongside the standard quantization of vacuum general relativity in loop quantum gravity.

  14. Massive gravity as a limit of bimetric gravity

    E-Print Network [OSTI]

    Martin-Moruno, Prado; Visser, Matt

    2013-01-01

    Massive gravity may be viewed as a suitable limit of bimetric gravity. The limiting procedure can lead to an interesting interplay between the "background" and "foreground" metrics in a cosmological context. The fact that in bimetric theories one always has two sets of metric equations of motion continues to have an effect even in the massive gravity limit. Thus, solutions of bimetric gravity in the limit of vanishing kinetic term are also solutions of massive gravity, but the contrary statement is not necessarily true.

  15. Quantum Gravity and Turbulence

    E-Print Network [OSTI]

    Vishnu Jejjala; Djordje Minic; Y. Jack Ng; Chia-Hsiung Tze

    2010-05-18

    We apply recent advances in quantum gravity to the problem of turbulence. Adopting the AdS/CFT approach we propose a string theory of turbulence that explains the Kolmogorov scaling in 3+1 dimensions and the Kraichnan and Kolmogorov scalings in 2+1 dimensions. In the gravitational context, turbulence is intimately related to the properties of spacetime, or quantum, foam.

  16. Isometrodynamics and Gravity

    E-Print Network [OSTI]

    Christian Wiesendanger

    2009-07-25

    Isometrodynamics (ID), the gauge theory of the group of volume-preserving diffeomorphisms of an "inner" D-dimensional flat space, is tentatively interpreted as a fundamental theory of gravity. Dimensional analysis shows that the Planck length l_P - and through it \\hbar and \\Gamma - enters the gauge field action linking ID and gravity in a natural way. Noting that the ID gauge field couples solely through derivatives acting on "inner" space variables all ID fields are Taylor-expanded in "inner" space. Integrating out the "inner" space variables yields an effective field theory for the coefficient fields with l_P^2 emerging as the expansion parameter. For \\hbar goint to zero only the leading order field does not vanish. This classical field couples to the matter Noether currents and charges related to the translation invariance in "inner" space. A model coupling this leading order field to a matter point source is established and solved. Interpreting the matter Noether charge in terms of gravitational mass Newton's inverse square law is finally derived for a static gauge field source and a slowly moving test particle. Gravity emerges as potentially related to field variations over "inner" space and might microscopically be described by the ID gauge field or equivalently by an infinite string of coefficient fields only the leading term of which is related to the macroscopical effects of gravity.

  17. STAFF FORECAST: AVERAGE RETAIL ELECTRICITY PRICES

    E-Print Network [OSTI]

    CALIFORNIA ENERGY COMMISSION STAFF FORECAST: AVERAGE RETAIL ELECTRICITY PRICES 2005 TO 2018 Mignon Marks Principal Author Mignon Marks Project Manager David Ashuckian Manager ELECTRICITY ANALYSIS OFFICE Sylvia Bender Acting Deputy Director ELECTRICITY SUPPLY DIVISION B.B. Blevins Executive Director

  18. Distributed Averaging Via Lifted Markov Chains

    E-Print Network [OSTI]

    Jung, Kyomin

    Motivated by applications of distributed linear estimation, distributed control, and distributed optimization, we consider the question of designing linear iterative algorithms for computing the average of numbers in a ...

  19. Thermal ghost imaging with averaged speckle patterns

    E-Print Network [OSTI]

    Shapiro, Jeffrey H.

    We present theoretical and experimental results showing that a thermal ghost imaging system can produce images of high quality even when it uses detectors so slow that they respond only to intensity-averaged (that is, ...

  20. Selling Geothermal Systems The "Average" Contractor

    E-Print Network [OSTI]

    Selling Geothermal Systems #12;The "Average" Contractor · History of sales procedures · Manufacturer Driven Procedures · What makes geothermal technology any harder to sell? #12;"It's difficult to sell a geothermal system." · It should

  1. Spacetime Average Density (SAD) cosmological measures

    SciTech Connect (OSTI)

    Page, Don N.

    2014-11-01

    The measure problem of cosmology is how to obtain normalized probabilities of observations from the quantum state of the universe. This is particularly a problem when eternal inflation leads to a universe of unbounded size so that there are apparently infinitely many realizations or occurrences of observations of each of many different kinds or types, making the ratios ambiguous. There is also the danger of domination by Boltzmann Brains. Here two new Spacetime Average Density (SAD) measures are proposed, Maximal Average Density (MAD) and Biased Average Density (BAD), for getting a finite number of observation occurrences by using properties of the Spacetime Average Density (SAD) of observation occurrences to restrict to finite regions of spacetimes that have a preferred beginning or bounce hypersurface. These measures avoid Boltzmann brain domination and appear to give results consistent with other observations that are problematic for other widely used measures, such as the observation of a positive cosmological constant.

  2. Average transmission probability of a random stack

    E-Print Network [OSTI]

    Yin Lu; Christian Miniatura; Berthold-Georg Englert

    2009-07-31

    The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower bounds. The upper bound, when used as an approximation for the transmission probability, is unreasonably good and we conjecture that it is asymptotically exact.

  3. Lorentz Breaking and Gravity

    E-Print Network [OSTI]

    R. Bluhm

    2013-07-22

    Gravitational theories with Lorentz violation must account for a number of possible features in order to be consistent theoretically and phenomenologically. A brief summary of these features is given here. They include evasion of a no-go theorem, connections between spontaneous Lorentz breaking and diffeomorphism breaking, the appearance of massless Nambu-Goldstone modes and massive Higgs modes, and the possibility of a Higgs mechanism in gravity.

  4. Gravity, Dimension, Equilibrium, & Thermodynamics

    E-Print Network [OSTI]

    Jerome Perez

    2006-03-30

    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.

  5. Massive Gravity from Higher Derivative Gravity with Boundary Conditions

    E-Print Network [OSTI]

    Minjoon Park; Lorenzo Sorbo

    2012-10-29

    With an appropriate choice of parameters, a higher derivative theory of gravity can describe a normal massive sector and a ghost massless sector. We show that, when defined on an asymptotically de Sitter spacetime with Dirichlet boundary conditions, such a higher derivative gravity can provide a framework for a unitary theory of massive gravity in four spacetime dimensions. The resulting theory is free not only of higher derivative ghosts but also of the Boulware-Deser mode.

  6. 8-Spinor Quantum Gravity

    E-Print Network [OSTI]

    Marcus S. Cohen

    2002-08-02

    Quantum gravity has been so elusive because we have tried to approach it by two paths which can never meet: quantum mechanics and general relativity. These contradict each other not only in superdense regimes, but also in the vacuum. We explore a straight road to quantum gravity here--the one mandated by Clifford-algebra covariance. This bridges the gap from microscales--where the massive Dirac propagator is a sum over null zig-zags--to macroscales--where we see the energy-momentum current, *T and the resulting Einstein curvature, *G. For massive particles, *T flows in the "cosmic time" direction, y^0--centrifugally in an expanding universe. Neighboring centrifugal currents of *T present opposite spacetime vorticities *G to the boundaries of each others' worldtubes, so they advect--i.e. attract, as we show here by integrating a Spin^c-4 Lagrangian by parts in the spinfluid regime. This boundary integral not only explains why stress-energy *T is the source for gravitational curvature *G, but also gives a value for the gravitational constant, kappa(x^0) that depends on the current scale factor of our expanding Friedmann 3-brane. On the microscopic scale, quantum gravity appears naturally as the statistical mechanics of null zig-zags of massive particles in "imaginary time," y^0.

  7. Polarized electron beams at milliampere average current

    SciTech Connect (OSTI)

    Poelker, Matthew

    2013-11-01

    This contribution describes some of the challenges associated with developing a polarized electron source capable of uninterrupted days-long operation at milliAmpere average beam current with polarization greater than 80%. Challenges will be presented in the context of assessing the required level of extrapolation beyond the performance of today's CEBAF polarized source operating at ~ 200 uA average current. Estimates of performance at higher current will be based on hours-long demonstrations at 1 and 4 mA. Particular attention will be paid to beam-related lifetime-limiting mechanisms, and strategies to construct a photogun that operate reliably at bias voltage > 350kV.

  8. Table 1. Real Average Transportation and Delivered Costs of Coal...

    U.S. Energy Information Administration (EIA) Indexed Site

    Real Average Transportation and Delivered Costs of Coal, By Year and Primary Transport Mode" "Year","Average Transportation Cost of Coal (Dollars per Ton)","Average Delivered Cost...

  9. Monitoring the Bulalo geothermal reservoir, Philippines, using precision gravity data

    SciTech Connect (OSTI)

    San Andres, R.B.; Pedersen, J.R.

    1993-10-01

    Precision gravity monitoring of the Bulalo geothermal field began in 1980 to estimate the natural mass recharge to the reservoir. Between 1980 and 1991, gravity decreases exceeding 2.5 {times} 10{sup {minus}6} N/kg (250 microgals) were observed in response to fluid withdrawals. A maximum rate of {minus}26 microgals per year was observed near the production center. Mass discharges predicted by recent reservoir simulation modeling generally match those inferred from the observed gravity data. According to simulation studies, no recharge occurred between 1980 and 1984. The mass recharge between 1984 and 1991 was estimated to be 30% of net fluid withdrawal during the same period, equivalent to an average rate of 175 kg/s (630 metric tons per hour).

  10. Geometric scalar theory of gravity

    SciTech Connect (OSTI)

    Novello, M.; Bittencourt, E.; Goulart, E.; Salim, J.M.; Toniato, J.D.; Moschella, U. E-mail: eduhsb@cbpf.br E-mail: egoulart@cbpf.br E-mail: toniato@cbpf.br

    2013-06-01

    We present a geometric scalar theory of gravity. Our proposal will be described using the ''background field method'' introduced by Gupta, Feynman, Deser and others as a field theory formulation of general relativity. We analyze previous criticisms against scalar gravity and show how the present proposal avoids these difficulties. This concerns not only the theoretical complaints but also those related to observations. In particular, we show that the widespread belief of the conjecture that the source of scalar gravity must be the trace of the energy-momentum tensor — which is one of the main difficulties to couple gravity with electromagnetic phenomenon in previous models — does not apply to our geometric scalar theory. From the very beginning this is not a special relativistic scalar gravity. The adjective ''geometric'' pinpoints its similarity with general relativity: this is a metric theory of gravity. Some consequences of this new scalar theory are explored.

  11. Laser Fusion Energy The High Average Power

    E-Print Network [OSTI]

    Laser Fusion Energy and The High Average Power Program John Sethian Naval Research Laboratory Dec for Inertial Fusion Energy with lasers, direct drive targets and solid wall chambers Lasers DPPSL (LLNL) Kr posters Snead Payne #12;Laser(s) Goals 1. Develop technologies that can meet the fusion energy

  12. Extracting gluon condensate from the average plaquette

    E-Print Network [OSTI]

    Taekoon Lee

    2015-03-27

    The perturbative contribution in the average plaquette is subtracted using Borel summation and the remnant of the plaquette is shown to scale as a dim-4 condensate. A critical review is presented of the renormalon subtraction scheme that claimed a dim-2 condensate. The extracted gluon condensate is compared with the latest result employing high order (35-loop) calculation in the stochastic perturbation theory.

  13. Entropic Gravity in Rindler Space

    E-Print Network [OSTI]

    Edi Halyo

    2011-04-13

    We show that Rindler horizons are entropic screens and gravity is an entropic force in Rindler space by deriving the Verlinde entropy formula from the focusing of light due to a mass close to the horizon. Consequently, gravity is also entropic in the near horizon regions of Schwarzschild and de Sitter space-times. In different limits, the entropic nature of gravity in Rindler space leads to the Bekenstein entropy bound and the uncertainty principle.

  14. Utility Rates API Version 2 is Live! | OpenEI Community

    Open Energy Info (EERE)

    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 QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) JumpGTZUtility Rates API Version 2 is Live! Home >

  15. Lorenz APIs and REST Services (Technical Report) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journalspectroscopy ofArticle) | SciTechPrinciplesstromal/stem cellsSciTechLorenz APIs

  16. Is Gravity an Entropic Force?

    E-Print Network [OSTI]

    Shan Gao

    2011-07-16

    The remarkable connections between gravity and thermodynamics seem to imply that gravity is not fundamental but emergent, and in particular, as Verlinde suggested, gravity is probably an entropic force. In this paper, we will argue that the idea of gravity as an entropic force is debatable. It is shown that there is no convincing analogy between gravity and entropic force in Verlinde's example. Neither holographic screen nor test particle satisfies all requirements for the existence of entropic force in a thermodynamics system. Furthermore, we show that the entropy increase of the screen is not caused by its statistical tendency to increase entropy as required by the existence of entropic force, but in fact caused by gravity. Therefore, Verlinde's argument for the entropic origin of gravity is problematic. In addition, we argue that the existence of a minimum size of spacetime, together with the Heisenberg uncertainty principle in quantum theory, may imply the fundamental existence of gravity as a geometric property of spacetime. This may provide a further support for the conclusion that gravity is not an entropic force.

  17. Dual gravity and E11

    E-Print Network [OSTI]

    Peter West

    2014-11-04

    We consider the equation of motion in the gravity sector that arises from the non-linear realisation of the semi-direct product of E11 and its first fundamental representation, denoted by l1, in four dimensions. This equation is first order in derivatives and at low levels relates the usual field of gravity to a dual gravity field. When the generalised space-time is restricted to be the usual four dimensional space-time we show that this equation does correctly describe Einstein's theory at the linearised level. We also comment on previous discussions of dual gravity.

  18. An Underlying Theory for Gravity

    E-Print Network [OSTI]

    Yuan K. Ha

    2012-08-14

    A new direction to understand gravity has recently been explored by considering classical gravity to be a derived interaction from an underlying theory. This underlying theory would involve new degrees of freedom at a deeper level and it would be structurally different from classical gravitation. It may conceivably be a quantum theory or a non-quantum theory. The relation between this underlying theory and Einstein's gravity is similar to the connection between statistical mechanics and thermodynamics. We discuss the apparent lack of evidence of any quantum nature of gravity in this context.

  19. Lifshitz Gravity for Lifshitz Holography

    E-Print Network [OSTI]

    Tom Griffin; Petr Horava; Charles M. Melby-Thompson

    2012-11-20

    We argue that Horava-Lifshitz (HL) gravity provides the minimal holographic dual for Lifshitz-type field theories with anisotropic scaling and dynamical exponent z. First we show that Lifshitz spacetimes are vacuum solutions of HL gravity, without need for additional matter. Then we perform holographic renormalization of HL gravity, and show how it reproduces the full structure of the z=2 anisotropic Weyl anomaly in dual field theories in 2+1 dimensions, while its minimal relativistic gravity counterpart yields only one of two independent central charges in the anomaly.

  20. Conversion of the LIMA1 tumor suppressor into an oncogenic LMO-like protein by API2-MALT1 paracaspase cleavage in MALT lymphoma

    E-Print Network [OSTI]

    Nie, Zilin; Du, Ming-Qing; McAllister-Lucas, Linda M.; Lucas, Peter C.; Bailey, Nathanael G.; Hogaboam, Cory M.; Lim, Megan S.; Elenitoba-Johnson, Kojo S. J.

    2015-01-08

    lymphomagenesis by cleavage of LIMA1?. Finally, to demonstrate the clinical relevance of API2-MALT1 targeting LIMA1 in B cell oncogenesis, LIMA1 proteolytic cleavage was examined by Western blot in cell lysates obtained from patient-derived API2-MALT1 positive...

  1. The role of information in gravity

    E-Print Network [OSTI]

    M. Spaans

    2009-07-24

    It is argued that particle-specific information on energy-momentum adjusts the strength of gravity. This form of gravity has no free parameters, preserves Einstein gravity locally and predicts 6 times stronger accelerations on galaxy scales.

  2. Gravity-Driven Intrusions in Stratified Fluids

    E-Print Network [OSTI]

    Maurer, Benjamin D.

    2011-01-01

    5.5.1 Five interleaving interfacial gravity currents 5.5.2Ten interleaving interfacial gravity currents . 5.6in Iceland showing multiple gravity-driven intrusions c ´

  3. HDF5-FastQuery: An API for Simplifying Access to Data Storage,Retrieval, Indexing and Querying

    SciTech Connect (OSTI)

    Bethel, E. Wes; Gosink, Luke; Shalf, John; Stockinger, Kurt; Wu,Kesheng

    2006-06-15

    This work focuses on research and development activities that bridge a gap between fundamental data management technology index, query, storage and retrieval and use of such technology in computational and computer science algorithms and applications. The work has resulted in a streamlined applications programming interface (API) that simplifies data storage and retrieval using the HDF5 data I/O library, and eases use of the FastBit compressed bitmap indexing software for data indexing/querying. The API, which we call HDF5-FastQuery, will have broad applications in domain sciences as well as associated data analysis and visualization applications.

  4. Average gluon and quark jet multiplicities

    E-Print Network [OSTI]

    A. V. Kotikov

    2014-11-30

    We show the results in [1,2] for computing the QCD contributions to the scale evolution of average gluon and quark jet multiplicities. The new results came due a recent progress in timelike small-x resummation obtained in the MSbar factorization scheme. They depend on two nonperturbative parameters with clear and simple physical interpretations. A global fit of these two quantities to all available experimental data sets demonstrates by its goodness how our results solve a longstandig problem of QCD. Including all the available theoretical input within our approach, alphas(Mz)=0.1199 +- 0.0026 has been obtained in the MSbar scheme in an approximation equivalent to next-to-next-to-leading order enhanced by the resummations of ln x terms through the NNLL level and of ln Q2 terms by the renormalization group. This result is in excellent agreement with the present world average.

  5. Gravity sans singularities

    E-Print Network [OSTI]

    K. H. Mariwalla

    2002-05-28

    Basis and limitations of singularity theorems for Gravity are examined. As singularity is a critical situation in course of time, study of time paths, in full generality of Equivalence principle, provides two mechanisms to prevent singularity. Resolution of singular Time translation generators into space of its orbits, and essential higher dimensions for Relativistic particle interactions has facets to resolve any real singularity problem. Conceptually, these varied viewpoints have a common denominator: arbitrariness in the definition of `energy' intrinsic to the space of operation in each case, so as to render absence of singularity a tautology for self-consistency of the systems.

  6. Gravity wraps Higgs boson

    E-Print Network [OSTI]

    Durmus A. Demir

    2011-12-11

    It is shown that, under a conformal transformation with reference to the Higgs field, the Higgs boson can be completely decoupled from electroweak interactions with no apparent change in known properties of leptons, quarks and vector bosons. Higgs boson becomes part of a scalar-tensor gravity which can be relevant for Dark Energy. It interacts with matter sector via higher-dimensional terms (e.g. neutrino Majorana mass), and via the fields (of new physics) whose masses are not generated by the Higgs mechanism. Dark Matter and two-Higgs-doublet model are the simplest examples.

  7. Lubricated viscous gravity currents

    E-Print Network [OSTI]

    Kowal, Katarzyna N.; Worster, M. Grae

    2015-02-10

    ) at their base. The presence of subglacial meltwater can be attributed to geothermal heating, frictional heating from glacier sliding, and ice melting under pressure from the weight of the ice † Email address for correspondence: K.Kowal@damtp.cam.ac.uk 2 K. N... -fed and a constant head was maintained in the reservoir. To minimize the amount Lubricated viscous gravity currents 15 mirror syringe pump reservoir glass sheet perspex sheet screen Golden Syrup Salt Solution 1 m Figure 6: Schematic of our experimental...

  8. Impact Ionization Model Using Average Energy and Average Square Energy of Distribution Function

    E-Print Network [OSTI]

    Dunham, Scott

    Impact Ionization Model Using Average Energy and Average Square Energy of Distribution Function Ken relaxation length, v sat ø h''i (¸ 0:05¯m), the energy distribution function is not well described calculation of impact ionization coefficient requires the use of a high energy distribution function because

  9. Reduced models for quantum gravity

    E-Print Network [OSTI]

    T. Thiemann

    1999-10-04

    The preceding talks given at this conference have dealt mainly with general ideas for, main problems of and techniques for the task of quantizing gravity canonically. Since one of the major motivations to arrange for this meeting was that it should serve as a beginner's introduction to canonical quantum gravity, we regard it as important to demonstrate the usefulness of the formalism by means of applying it to simplified models of quantum gravity, here formulated in terms of Ashtekar's new variables. From the various, completely solvable, models that have been discussed in the literature we choose those that we consider as most suitable for our pedagogical reasons, namely 2+1 gravity and the spherically symmetric model. The former model arises from a dimensional, the latter from a Killing reduction of full 3+1 gravity. While 2+1 gravity is usually treated in terms of closed topologies without boundary of the initial data hypersurface, the toplogy for the spherically symmetric system is chosen to be asymptotically flat. Finally, 2+1 gravity is more suitably quantized using the loop representation while spherically symmetric gravity is easier to quantize via the self-dual representation. Accordingly, both types of reductions, both types of topologies and both types of representations that are mainly employed in the literature in the context of the new variables come into practice. What makes the discussion especially clear is the fact that for both models the reduced phase space turns out to be finitely dimensional.

  10. Time-dependent angularly averaged inverse transport

    E-Print Network [OSTI]

    Guillaume Bal; Alexandre Jollivet

    2009-05-07

    This paper concerns the reconstruction of the absorption and scattering parameters in a time-dependent linear transport equation from knowledge of angularly averaged measurements performed at the boundary of a domain of interest. We show that the absorption coefficient and the spatial component of the scattering coefficient are uniquely determined by such measurements. We obtain stability results on the reconstruction of the absorption and scattering parameters with respect to the measured albedo operator. The stability results are obtained by a precise decomposition of the measurements into components with different singular behavior in the time domain.

  11. Reynolds-Averaged Navier-Stokes

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMassR&D100Nationalquestionnaires 0serial codesReversingprovedReynolds-Averaged

  12. API - 2 

    E-Print Network [OSTI]

    Unknown

    2011-08-17

    Association, Maxwell AFB, Alabama. ?The 42 nd Bombardment Squadron was placed on a non-operational status (zero strength) in October 1945, after active participation in World War II. The squadron was assigned to the Twentieth Air Force 23 April...-1 42nd Bombardment Squadron (H) Monthly Squadron Histories and Documents 1 May 1946 ? 31 July 1946. 42nd Bombardment Squadron (H), 11th Bombardment Group (H), 7th Air Force (1941-January 1943); 13th Air Force (January 1943...

  13. SNMP API

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II) byMultidayAlumni > The2/01/12 Page 1 ofSuper HeavySLEPcService in

  14. The 2009 World Average of $?_s$

    E-Print Network [OSTI]

    Siegfried Bethke

    2009-08-15

    Measurements of $\\alpha_s$, the coupling strength of the Strong Interaction between quarks and gluons, are summarised and an updated value of the world average of $\\alpha_s (M_Z)$ is derived. Building up on previous reviews, special emphasis is laid on the most recent determinations of $\\alpha_s$. These are obtained from $\\tau$-decays, from global fits of electroweak precision data and from measurements of the proton structure function $\\F_2$, which are based on perturbative QCD calculations up to $O(\\alpha_s^4)$; from hadronic event shapes and jet production in $\\epem$ annihilation, based on $O(\\alpha_s^3) $ QCD; from jet production in deep inelastic scattering and from $\\Upsilon$ decays, based on $O(\\alpha_s^2) $ QCD; and from heavy quarkonia based on unquenched QCD lattice calculations. Applying pragmatic methods to deal with possibly underestimated errors and/or unknown correlations, the world average value of $\\alpha_s (M_Z)$ results in $\\alpha_s (M_Z) = 0.1184 \\pm 0.0007$. The measured values of $\\alpha_s (Q)$, covering energy scales from $Q \\equiv \\mtau = 1.78$ GeV to 209 GeV, exactly follow the energy dependence predicted by QCD and therefore significantly test the concept af Asymptotic Freedom.

  15. Renormalization, averaging, conservation laws and AdS (in)stability

    E-Print Network [OSTI]

    Ben Craps; Oleg Evnin; Joris Vanhoof

    2015-01-19

    We continue our analytic investigations of non-linear spherically symmetric perturbations around the anti-de Sitter background in gravity-scalar field systems, and focus on conservation laws restricting the (perturbatively) slow drift of energy between the different normal modes due to non-linearities. We discover two conservation laws in addition to the energy conservation previously discussed in relation to AdS instability. A similar set of three conservation laws was previously noted for a self-interacting scalar field in a non-dynamical AdS background, and we highlight the similarities of this system to the fully dynamical case of gravitational instability. The nature of these conservation laws is best understood through an appeal to averaging methods which allow one to derive an effective Lagrangian or Hamiltonian description of the slow energy transfer between the normal modes. The conservation laws in question then follow from explicit symmetries of this averaged effective theory.

  16. Spin-gravity coupling and gravity-induced quantum phases

    E-Print Network [OSTI]

    Giorgio Papini

    2007-09-06

    External gravitational fields induce phase factors in the wave functions of particles. The phases are exact to first order in the background gravitational field, are manifestly covariant and gauge invariant and provide a useful tool for the study of spin-gravity coupling and of the optics of particles in gravitational or inertial fields. We discuss the role that spin-gravity coupling plays in particular problems.

  17. Gravity's Rainbow: a bridge towards Horava-Lifshitz gravity

    E-Print Network [OSTI]

    Remo Garattini; Emmanuel N. Saridakis

    2014-11-25

    We investigate the connection between Gravity's Rainbow and Horava-Lifshitz gravity, since both theories incorporate a modification in the UltraViolet regime which improves their quantum behavior at the cost of the Lorentz invariance loss. In particular, extracting the Wheeler-De Witt equations of the two theories in the case of Friedmann-Lemaitre-Robertson-Walker and spherically symmetric geometries, we establish a correspondence that bridges them.

  18. Fact #744: September 10, 2012 Average New Light Vehicle Price...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    4: September 10, 2012 Average New Light Vehicle Price Grows Faster than Average Used Light Vehicle Price Fact 744: September 10, 2012 Average New Light Vehicle Price Grows Faster...

  19. Cosmological perturbations in unimodular gravity

    SciTech Connect (OSTI)

    Gao, Caixia; Brandenberger, Robert H.; Cai, Yifu; Chen, Pisin E-mail: rhb@hep.physics.mcgill.ca E-mail: chen@slac.stanford.edu

    2014-09-01

    We study cosmological perturbation theory within the framework of unimodular gravity. We show that the Lagrangian constraint on the determinant of the metric required by unimodular gravity leads to an extra constraint on the gauge freedom of the metric perturbations. Although the main equation of motion for the gravitational potential remains the same, the shift variable, which is gauge artifact in General Relativity, cannot be set to zero in unimodular gravity. This non-vanishing shift variable affects the propagation of photons throughout the cosmological evolution and therefore modifies the Sachs-Wolfe relation between the relativistic gravitational potential and the microwave temperature anisotropies. However, for adiabatic fluctuations the difference between the result in General Relativity and unimodular gravity is suppressed on large angular scales. Thus, no strong constraints on the theory can be derived.

  20. Gravity Currents in Aquatic Canopies

    E-Print Network [OSTI]

    Tanino, Yukie

    A lock exchange experiment is used to investigate the propagation of gravity currents through a random array of rigid, emergent cylinders which represents a canopy of aquatic plants. As canopy drag increases, the propagating ...

  1. Gravity as an Entropic Phenomenon

    E-Print Network [OSTI]

    Abhiram Chivukula

    2010-11-19

    The unification of gravity with the three other forces has been an important goal of physics for some time now, because a quantum theory of gravity is necessary to explain the universe at its earliest moments. Its pursuit has largely assumed gravity's independent existence, but E. Verlinde proposed that gravity is not a fundamental force but a macroscopic phenomenon that emerges as a result of thermodynamic principles applied to the information of mass distributions. Under this framework we consider the roles played by quantum microstates, entanglement, information theory, the AdS/CFT Correspondence, and String Theory in general. We also ask whether Verlinde's proposal suggests that action principles should be thermodynamic in nature.

  2. Gravity as an Entropic Phenomenon

    E-Print Network [OSTI]

    Chivukula, Abhiram

    2010-01-01

    The unification of gravity with the three other forces has been an important goal of physics for some time now, because a quantum theory of gravity is necessary to explain the universe at its earliest moments. Its pursuit has largely assumed gravity's independent existence, but E. Verlinde proposed that gravity is not a fundamental force but a macroscopic phenomenon that emerges as a result of thermodynamic principles applied to the information of mass distributions. Under this framework we consider the roles played by quantum microstates, entanglement, information theory, the AdS/CFT Correspondence, and String Theory in general. We also ask whether Verlinde's proposal suggests that action principles should be thermodynamic in nature.

  3. Testing Gravity Theories Using Stars

    E-Print Network [OSTI]

    Jeremy Sakstein; Bhuvnesh Jain; Vinu Vikram

    2014-09-12

    Modified theories of gravity have received a renewed interest due to their ability to account for the cosmic acceleration. In order to satisfy the solar system tests of gravity, these theories need to include a screening mechanism that hides the modifications on small scales. One popular and well-studied theory is chameleon gravity. Our own galaxy is necessarily screened, but less dense dwarf galaxies may be unscreened and their constituent stars can exhibit novel features. In particular, unscreened stars are brighter, hotter and more ephemeral than screened stars in our own galaxy. They also pulsate with a shorter period. In this essay, we exploit these new features to constrain chameleon gravity to levels three orders of magnitude lower the previous measurements. These constraints are currently the strongest in the literature.

  4. Fact #849: December 1, 2014 Midsize Hybrid Cars Averaged 51%...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    cars are for gasoline cars only. Fuel economy average is the production-weighted harmonic mean. 2014 data are preliminary. Fact 849 Dataset Supporting Information Average...

  5. Fact #744: September 10, 2012 Average New Light Vehicle Price Grows Faster than Average Used Light Vehicle Price

    Office of Energy Efficiency and Renewable Energy (EERE)

    In 2011 the average used light vehicle price was 36% higher than in 1990, while the average new light vehicle price was 67% higher than it was in 1990. The average price of a used vehicle had been...

  6. The Average Mass Profile of Galaxy Clusters

    E-Print Network [OSTI]

    R. G. Carlberg; H. K. C. Yee; E. Ellingson; S. L. Morris; R. Abraham; P. Gravel; C. J. Pritchet; T. Smecker-Hane; F. D. A. Hartwick; J. E. Hesser; J. B. Hutchings; J. B. Oke

    1997-05-23

    The average mass density profile measured in the CNOC cluster survey is well described with the analytic form rho(r)=A/[r(r+a_rho)^2], as advocated on the basis on n-body simulations by Navarro, Frenk & White. The predicted core radii are a_rho=0.20 (in units of the radius where the mean interior density is 200 times the critical density) for an Omega=0.2 open CDM model, or a_rho=0.26 for a flat Omega=0.2 model, with little dependence on other cosmological parameters for simulations normalized to the observed cluster abundance. The dynamically derived local mass-to-light ratio, which has little radial variation, converts the observed light profile to a mass profile. We find that the scale radius of the mass distribution, 0.20<= a_rho <= 0.30 (depending on modeling details, with a 95% confidence range of 0.12-0.50), is completely consistent with the predicted values. Moreover, the profiles and total masses of the clusters as individuals can be acceptably predicted from the cluster RMS line-of-sight velocity dispersion alone. This is strong support of the hierarchical clustering theory for the formation of galaxy clusters in a cool, collisionless, dark matter dominated universe.

  7. Dualities and Emergent Gravity: Gauge/Gravity Duality

    E-Print Network [OSTI]

    Sebastian de Haro

    2015-09-09

    In this paper I develop a framework for relating dualities and emergence: two notions that are close to each other but also exclude one another. I adopt the conception of duality as 'isomorphism', cashing it out in terms of three conditions. These three conditions prompt two conceptually different ways in which a duality can be modified to make room for emergence; and I argue that this exhausts the possibilities for combining dualities and emergence (via coarse-graining). I apply this framework to gauge/gravity dualities, considering in detail three examples: AdS/CFT, Verlinde's scheme, and black holes. My main point about gauge/gravity dualities is that the theories involved, qua theories of gravity, must be background-independent. I distinguish two senses of background-independence: (i) minimalistic and (ii) extended. The former is sufficiently strong to allow for a consistent theory of quantum gravity; and AdS/CFT is background-independent on this account; while Verlinde's scheme best fits the extended sense. I argue that this extended sense should be applied with some caution: on pain of throwing the baby (general relativity) out with the bath-water (extended background-independence). Nevertheless, it is an interesting and potentially fruitful heuristic principle for quantum gravity theory construction. The interpretation of dualities is articulated in terms of: (i) epistemic and metaphysical commitments; (ii) parts vs. wholes. I then analyse the emergence of gravity in gauge/gravity dualities in terms of the two available conceptualisations of emergence; and I show how emergence in AdS/CFT and in Verlinde's scenario differ from each other. Finally, I give a novel derivation of the Bekenstein-Hawking black hole entropy formula based on Verlinde's scheme; the derivation sheds light on several aspects of Verlinde's scheme and how it compares to Bekenstein's original calculation.

  8. Gravity's smoking gun?

    E-Print Network [OSTI]

    E. Gaztanaga; R. Juszkiewicz

    2001-08-21

    We present a new constraint on the biased galaxy formation picture. Gravitational instability theory predicts that the two-point mass density correlation function, \\xi(r), has an inflection point at the separation r=r_0, corresponding to the boundary between the linear and nonlinear regime of clustering, \\xi = 1. We show how this feature can be used to constrain the square of the biasing parameter, b^2 = \\xi_g / \\xi on scales r = r_0, where \\xi_g is the galaxy-galaxy correlation function, allowed to differ from \\xi. We apply our method to real data: the \\xi_g(r), estimated from the APM galaxy survey. Our results suggest that the APM galaxies trace the mass at separations r > 5 Mpc/h, where h is the Hubble constant in units of 100 km/s Mpc. The present results agree with earlier studies, based on comparing higher order correlations in the APM with weakly non-linear perturbation theory. Both approaches constrain the "b" factor to be within 20% of unity. If the existence of the feature we identified in the APM \\xi_g(r) -- the inflection point near \\xi_g = 1 -- is confirmed by more accurate surveys, we may have discovered gravity's smoking gun: the long awaited ``shoulder'' in \\xi, predicted by Gott and Rees 25 years ago.

  9. May Gravity detect Tsunami ?

    E-Print Network [OSTI]

    D. Fargion

    2005-11-23

    The present gravitational wave detectors are reaching lowest metric deviation fields able to detect galactic and extra-galactic gravitational waves, related to Supernova explosions up to Virgo cluster. The same gravitational wave detector are nevertheless almost able to reveal, in principle, near field Newtonian gravitational perturbations due to fast huge mass displacements as the ones occurring during largest Earth-Quake or Tsunami as the last on 26nd December 2004 in Asiatic area. Virgo and Ligo detector are unfortunately recording on high frequencies (above tens Hz) while the signal of the Tsunami lay at much lower range (below 0.1 Hz). Nevertheless prompt gravitational near field deformation by the Tsunami might reach the future LISA threshold sensitivity and frequency windows if such an array is located nearby (3000-10000) km distances. Unfortunately the present LISA system should be located at Lagrange point too far (1.5 million km. far away). We note however that the later continental mass rearrangement and their gravitational field assessment on Earth must induce, for Richter Magnitude 9-like Tsunami, a different terrestrial inertia momentum and a different principal rotation axis. In conclusion we remind that gravitational geodetic deviation on new precise satellites (GOCE 2006), assisted by GPS network, might nevertheless reach in the near future the needed threshold and accuracy to reveal Tsunami by their prompt tidal gravity field deviations . An array of such geoid detector maybe correlated with LISA-like satellite on Earth orbits may offer the fastest alarm system.

  10. the average weight of Connecticut River fish was considerably less (Table 1). The difference in average

    E-Print Network [OSTI]

    the average weight of Connecticut River fish was considerably less (Table 1). The difference in the Connecticut River basin. Fisheries (Bethesda) 7(6): 2-11. POTTER. I. C.· F. W. H. BEAMISH, AND B. G. H. Freshwater fishes of Connecticut. State Geol. Nat. Hist. Servo Conn.· Dep. Environ. Prot., Bull. 101, 134 p

  11. Crustal structure across the Campeche Escarpment, Gulf of Mexico, from gravity data 

    E-Print Network [OSTI]

    Henderson, Garry Couch

    1962-01-01

    in counter units after the Browne correction has been applied. A continuous drive chart records the instantaneous and averaged beam positions; the slope of the averaged beam position multiplied by a constant yields the gravity value in counter units... sufficiently calm to provide measurements at relatively small and uniform horizontal accelerations. An adequate number of land fixes wi. th Alacran Reef afforded good navigational control as did clear skies for celestial fixes. Hence, both the gravi. ty...

  12. Climate variability according to triple saros gravity cycles

    E-Print Network [OSTI]

    William R. Livingston

    2013-06-03

    I describe a climate model which corresponds directly to eclipse cycles. The theory is based upon a similarity between the 54 year triple saros eclipse period and the periodicity of drought. I argue that eclipse shadows are an indication of gravity cycles, and that variable lunar gravitation is the most significant aspect of the eclipse process. I reinforce the idea that lunar gravitational forcing has a profound effect on the water vapor in Earth's atmosphere, and can affect the density and location of clouds. I explore the possibility that decadal variability of ocean surface levels may be explained by triple saros gravity cycles. I point out that lunar gravitation was excluded from the most significant climate report of 2007, and that climate data contradictions have been overlooked by researchers. I focus on the value of data that has not been aggregated into global averages. I touch upon the history of global warming, and I offer predictions based upon 54 year climate periodicity.

  13. Conformal Lifshitz Gravity from Holography

    E-Print Network [OSTI]

    Tom Griffin; Petr Horava; Charles M. Melby-Thompson

    2012-04-03

    We show that holographic renormalization of relativistic gravity in asymptotically Lifshitz spacetimes naturally reproduces the structure of gravity with anisotropic scaling: The holographic counterterms induced near anisotropic infinity take the form of the action for gravity at a Lifshitz point, with the appropriate value of the dynamical critical exponent $z$. In the particular case of 3+1 bulk dimensions and $z=2$ asymptotic scaling near infinity, we find a logarithmic counterterm, related to anisotropic Weyl anomaly of the dual CFT, and show that this counterterm reproduces precisely the action of conformal gravity at a $z=2$ Lifshitz point in 2+1 dimensions, which enjoys anisotropic local Weyl invariance and satisfies the detailed balance condition. We explain how the detailed balance is a consequence of relations among holographic counterterms, and point out that a similar relation holds in the relativistic case of holography in $AdS_5$. Upon analytic continuation, analogous to the relativistic case studied recently by Maldacena, the action of conformal gravity at the $z=2$ Lifshitz point features in the ground-state wavefunction of a gravitational system with an interesting type of spatial anisotropy.

  14. New Models of f(R) Theories of Gravity

    E-Print Network [OSTI]

    J. Kluson

    2009-11-04

    We introduce new models of f(R) theories of gravity that are generalization of Horava-Lifshitz gravity.

  15. The Gravity Field of the Earth and Coriolis Effects.... The gravity field

    E-Print Network [OSTI]

    Riser, Stephen C.

    The Gravity Field of the Earth and Coriolis Effects.... The gravity field Stationary particles #12;Gravity.... Newton's Universal Law of Gravitation: The force between any two particles having.673 ×10-11 newton-meter2/kilogram2) #12;Gravity.... In vector form, or, 21 è force on 2 due to 1 12 è

  16. Modified Entropic Gravity and Cosmology

    E-Print Network [OSTI]

    Miguel Zumalacarregui

    2012-02-06

    It has been recently proposed that gravity might be an entropic force. Although a well defined fundamental description for such a mechanism is still lacking, it is still possible to address the viability of phenomenological models of entropic-inspired modified gravities. I will summarize some recent work directed to using cosmology as a tool to constraint scenarios in which the modifications are aimed to explain the physics behind dark energy and inflation. A phenomenological modification is able to explain cosmic acceleration at the background level and fit observations, but simple inflation models with higher curvature corrections are in conflict with late time matter domination.

  17. Starobinsky Model in Rainbow Gravity

    E-Print Network [OSTI]

    Chatrabhuti, Auttakit; Channuie, Phongpichit

    2015-01-01

    In this work, we study Starobinsky model of inflation in the context of gravity's rainbow theory. We propose that gravity rainbow functions can be written in the power-law form of the Hubble parameter. We present a detailed derivation of the spectral index of curvature perturbation and the tensor-to-scalar ratio and compare the predictions of our models with Planck 2015 data. We discover, by taking $N_{k}=70$ e-folds and requiring our predictions to agree with the Planck data at the one sigma confidence level, the rainbow parameter would satisfy $\\lambda\\lesssim 1.0$.

  18. de Sitter gravity/Euclidean conformal gravity correspondence

    E-Print Network [OSTI]

    Chatterjee, Atreya

    2015-01-01

    The holographic dual of a gravitational theory around the de Sitter background is argued to be a Euclidean conformal gravity theory in one fewer dimensions. The measure for the holographic theory naturally includes a sum over topologies as well as conformal structures.

  19. Gravity Transform for Input Conditioning in

    E-Print Network [OSTI]

    Paiva, António R. C.

    Gravity Transform for Input Conditioning in Brain Machine Interfaces António R. C. Paiva, José C. Motivation 2. Methods i. Gravity Transform ii. Modeling and output sensitivity analysis 3. Data Analysis #12;3 Outline 1. Motivation 2. Methods i. Gravity Transform ii. Modeling and output sensitivity analysis 3. Data

  20. Emergent 4D Gravity from Matrix Models

    E-Print Network [OSTI]

    Harold Steinacker

    2007-12-19

    Recent progress in the understanding of gravity on noncommutative spaces is discussed. A gravity theory naturally emerges from matrix models of noncommutative gauge theory. The effective metric depends on the dynamical Poisson structure, absorbing the degrees of freedom of the would-be U(1) gauge field. The gravity action is induced upon quantization.

  1. Fact #671: April 18, 2011 Average Truck Speeds | Department of...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    2011 Average Truck Speeds The Federal Highway Administration studies traffic volume and flow on major truck routes by tracking more than 500,000 trucks. The average speed of trucks...

  2. Fact #889: September 7, 2015 Average Diesel Price Lower than...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    9: September 7, 2015 Average Diesel Price Lower than Gasoline for the First Time in Six Years Fact 889: September 7, 2015 Average Diesel Price Lower than Gasoline for the First...

  3. Fact #614: March 15, 2010 Average Age of Household Vehicles

    Broader source: Energy.gov [DOE]

    The average age of household vehicles has increased from 6.6 years in 1977 to 9.2 years in 2009. Pickup trucks have the oldest average age in every year listed. Sport utility vehicles (SUVs), first...

  4. Higher Derivative Gravity from the Universal Renormalization Group Machine

    E-Print Network [OSTI]

    F. Saueressig; K. Groh; S. Rechenberger; O. Zanusso

    2012-02-28

    We study the renormalization group flow of higher derivative gravity, utilizing the functional renormalization group equation for the average action. Employing a recently proposed algorithm, termed the universal renormalization group machine, for solving the flow equation, all the universal features of the one-loop beta-functions are recovered. While the universal part of the beta-functions admits two fixed points, we explicitly show that the existence of one of them depends on the choice of regularization scheme, indicating that it is most probably unphysical.

  5. Averaging top quark results in Run 2 M. Strovink

    E-Print Network [OSTI]

    Strovink, Mark

    average (cont'd) The pie chart shows the relative weights of the five input measurements in the world

  6. Improving climate change detection through optimal seasonal averaging: the

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Improving climate change detection through optimal seasonal averaging: the case of the North. (2015) Improving climate change detection through optimal seasonal averaging: the case of the North;Improving climate change detection through optimal seasonal averaging:1 the case of the North Atlantic jet

  7. Engineering Grads Earn The Most Major Average Salary

    E-Print Network [OSTI]

    Shahabi, Cyrus

    Engineering Grads Earn The Most Table Major Average Salary Offer Petroleum Engineering $86/Aeronautical/Astronautical Engineering $57,231 Information Sciences & Systems $54,038 Source: Winter 2010 Salary Survey, National was the fourth most lucrative degree, with graduates starting at $61,205 on average. The average salary

  8. High-gravity central stars

    E-Print Network [OSTI]

    Thomas Rauch

    2006-07-11

    NLTE spectral analyses of high-gravity central stars by means of state-of-the-art model atmosphere techniques provide information about the precursor AGB stars. The hydrogen-deficient post-AGB stars allow investigations on the intershell matter which is apparently exhibited at the stellar surface. We summarize recent results from imaging, spectroscopy, and spectropolarimetry.

  9. Gravity and the Fermion Mass

    E-Print Network [OSTI]

    Kenneth Dalton

    2010-06-11

    It is shown that gravity generates mass for the fermion. It does so by coupling directly with the spinor field. The coupling term is invariant with respect to the electroweak gauge group $ U(1) \\otimes SU(2)_L. $ It replaces the fermion mass term $ m\\bar{\\psi} \\psi $.

  10. Overlap Fermion in External Gravity

    E-Print Network [OSTI]

    Hiroto So; Masashi Hayakawa; Hiroshi Suzuki

    2006-12-12

    On a lattice, we construct an overlap Dirac operator which describes the propagation of a Dirac fermion in external gravity. The local Lorentz symmetry is manifestly realized as a lattice gauge symmetry, while the general coordinate invariance is expected to be restored only in the continuum limit. The lattice index density in the presence of a gravitational field is calculated.

  11. Cosmological Hints of Modified Gravity ?

    E-Print Network [OSTI]

    Eleonora Di Valentino; Alessandro Melchiorri; Joseph Silk

    2015-09-24

    The recent measurements of Cosmic Microwave Background temperature and polarization anisotropies made by the Planck satellite have provided impressive confirmation of the $\\Lambda$CDM cosmological model. However interesting hints of slight deviations from $\\Lambda$CDM have been found, including a $95 \\%$ c.l. preference for a "modified gravity" structure formation scenario. In this paper we confirm the preference for a modified gravity scenario from Planck 2015 data, find that modified gravity solves the so-called $A_{lens}$ anomaly in the CMB angular spectrum, and constrains the amplitude of matter density fluctuations to $\\sigma_8=0.815_{-0.048}^{+0.032}$, in better agreement with weak lensing constraints. Moreover, we find a lower value for the reionization optical depth of $\\tau=0.059\\pm0.020$ (to be compared with the value of $\\tau= 0.079 \\pm 0.017$ obtained in the standard scenario), more consistent with recent optical and UV data. We check the stability of this result by considering possible degeneracies with other parameters, including the neutrino effective number, the running of the spectral index and the amount of primordial helium. The indication for modified gravity is still present at about $95\\%$ c.l., and could become more significant if lower values of $\\tau$ were to be further confirmed by future cosmological and astrophysical data.

  12. Liouville quantum gravity and KPZ

    E-Print Network [OSTI]

    Duplantier, Bertrand

    Consider a bounded planar domain D, an instance h of the Gaussian free field on D, with Dirichlet energy ... and a constant 0[less than or equal to]?<2. The Liouville quantum gravity measure on D is the weak limit as ...

  13. Astrophysical tests of modified gravity

    E-Print Network [OSTI]

    Sakstein, Jeremy Aaron

    2014-10-07

    galaxies from our own. This means that the inferred distance to an unscreened galaxy using a stellar effect that depends on the law gravity will not agree with a measurement using a different method that is insensitive gravitational physics. We exploit...

  14. The Dark Gravity model predictions for Gravity Probe B

    E-Print Network [OSTI]

    Frederic Henry-Couannier

    2007-10-23

    The previous version of this article gave erroneous predictions. The correct uptodate predictions can be found in the section devoted to gravitomagnetism in the living review of the Dark Gravity theory: gr-qc/0610079 The most natural prediction is zero frame dragging and the same geodetic effect as predicted by GR. However, a straightforward extension of the theory could lead to the same frame-dragging as in GR.

  15. New Branches of Massive Gravity

    E-Print Network [OSTI]

    Comelli, Denis; Koyama, Kazuya; Pilo, Luigi; Tasinato, Gianmassimo

    2015-01-01

    The basic building block for Lorentz invariant and ghost free massive gravity is the square root of the combination $g^{-1}\\eta\\,$, where $g^{-1}$ is the inverse of the physical metric and $\\eta$ is a reference metric. Since the square root of a matrix is not uniquely defined, it is possible to have physically inequivalent potentials corresponding to different branches. We show that around Minkowski background the only perturbatively well defined branch is the potential proposed by de Rham, Gabadadze and Tolley. On the other hand, if Lorentz symmetry is broken spontaneously, other potentials exist with a standard perturbative expansion. We show this explicitly building new Lorentz invariant, ghost-free massive gravity potentials for theories that in the background preserve rotational invariance, but break Lorentz boosts.

  16. Nanodiamond interferometry meets quantum gravity

    E-Print Network [OSTI]

    Albrecht, Andreas; Plenio, Martin B

    2014-01-01

    Interferometry with massive particles may have the potential to explore the limitations of standard quantum mechanics in particular where it concerns its boundary with general relativity and the yet to be developed theory of quantum gravity. This development is hindered considerably by the lack of experimental evidence and testable predictions. Analyzing effects that appear to be common to many of such theories, such as a modification of the energy dispersion and of the canonical commutation relation within the standard framework of quantum mechanics, has been proposed as a possible way forward. Here we analyze in some detail the impact of a modified energy-momentum dispersion in a Ramsey-Bord\\'e setup and provide achievable bounds of these correcting terms when operating such an interferometer with nanodiamonds. Thus, taking thermal and gravitational disturbances into account will show that without specific prerequisites, quantum gravity modifications may in general be suppressed requiring a revision of prev...

  17. Hybrid metric-Palatini gravity

    E-Print Network [OSTI]

    Capozziello, Salvatore; Koivisto, Tomi S; Lobo, Francisco S N; Olmo, Gonzalo J

    2015-01-01

    Recently, the phenomenology of f(R) gravity has been scrutinized motivated by the possibility to account for the self-accelerated cosmic expansion without invoking dark energy sources. Besides, this kind of modified gravity is capable of addressing the dynamics of several self-gravitating systems alternatively to the presence of dark matter. It has been established that both metric and Palatini versions of these theories have interesting features but also manifest severe and different downsides. A hybrid combination of theories, containing elements from both these two formalisms, turns out to be also very successful accounting for the observed phenomenology and is able to avoid some drawbacks of the original approaches. This article reviews the formulation of this hybrid metric-Palatini approach and its main achievements in passing the local tests and in applications to astrophysical and cosmological scenarios, where it provides a unified approach to the problems of dark energy and dark matter.

  18. Quantum Gravity at the LHC

    E-Print Network [OSTI]

    Xavier Calmet; Priscila de Aquino

    2009-10-08

    It has recently been shown that if there is a large hidden sector in Nature, the scale of quantum gravity could be much lower than traditionally expected. We study the production of massless gravitons at the LHC and compare our results to those obtained in extra dimensional models. The signature in both cases is missing energy plus jets. In case of non observation, the LHC could be used to put the tightest limit to date on the value of the Planck mass.

  19. Quantum gravity without Lorentz invariance

    E-Print Network [OSTI]

    Sotiriou, Thomas P; Weinfurtner, Silke

    2009-01-01

    There has been a significant surge of interest in Horava's model for 3+1 dimensional quantum gravity, this model being based on anisotropic scaling at a z=3 Lifshitz point. Horava's model, and its variants, show dramatically improved ultra-violet behaviour at the cost of exhibiting violation of Lorentz invariance at ultra-high momenta. Following up on our earlier note, [arXiv:0904.4464 [hep-th

  20. Orbit-averaged guiding-center Fokker-Planck operator

    SciTech Connect (OSTI)

    Brizard, A. J. [Department of Chemistry and Physics, Saint Michael's College, Colchester, Vermont 05439 (United States); Decker, J.; Peysson, Y.; Duthoit, F.-X. [CEA, IRFM, Saint-Paul-lez-Durance F-13108 (France)

    2009-10-15

    A general orbit-averaged guiding-center Fokker-Planck operator suitable for the numerical analysis of transport processes in axisymmetric magnetized plasmas is presented. The orbit-averaged guiding-center operator describes transport processes in a three-dimensional guiding-center invariant space: the orbit-averaged magnetic-flux invariant {psi}, the minimum-B pitch-angle coordinate {xi}{sub 0}, and the momentum magnitude p.

  1. Anisotropy of Charpy Properties in API-X80 Steels MinSung Jooa, Dong-Woo Suha, Jin-Ho Baeb and H. K. D. H. Bhadeshiaa,c

    E-Print Network [OSTI]

    Cambridge, University of

    } for ductile fracture, {110} or {001} for cleavage fracture (+) · Distribution of grains which have. Anisotropic behavior in Charpy toughness of API-X80 steel Summary 2010 Autumn Conference of the Korean. API-X80 steel has two main factors for toughness anisotropy, the one is the delamination phenomenon

  2. Solid Holography and Massive Gravity

    E-Print Network [OSTI]

    Alberte, Lasma; Khmelnitsky, Andrei; Pujolas, Oriol

    2015-01-01

    Momentum dissipation is an important ingredient in condensed matter physics that requires a translation breaking sector. In the bottom-up gauge/gravity duality, this implies that the gravity dual is massive. We start here a systematic analysis of holographic massive gravity (HMG) theories, which admit field theory dual interpretations and which, therefore, might store interesting condensed matter applications. We show that there are many phases of HMG that are fully consistent effective field theories and which have been left overlooked in the literature. The most important distinction between the different HMG phases is that they can be clearly separated into solids and fluids. This can be done both at the level of the unbroken spacetime symmetries as well as concerning the elastic properties of the dual materials. We extract the modulus of rigidity of the solid HMG black brane solutions and show how it relates to the graviton mass term. We also consider the implications of the different HMGs on the electric...

  3. Emergent Horava gravity in graphene

    SciTech Connect (OSTI)

    Volovik, G.E.; L. D. Landau Institute for Theoretical Physics, Kosygina 2, 119334 Moscow ; Zubkov, M.A.

    2014-01-15

    First of all, we reconsider the tight-binding model of monolayer graphene, in which the variations of the hopping parameters are allowed. We demonstrate that the emergent 2D Weitzenbock geometry as well as the emergent U(1) gauge field appear. The emergent gauge field is equal to the linear combination of the components of the zweibein. Therefore, we actually deal with the gauge fixed version of the emergent 2+1 D teleparallel gravity. In particular, we work out the case, when the variations of the hopping parameters are due to the elastic deformations, and relate the elastic deformations with the emergent zweibein. Next, we investigate the tight-binding model with the varying intralayer hopping parameters for the multilayer graphene with the ABC stacking. In this case the emergent 2D Weitzenbock geometry and the emergent U(1) gauge field appear as well, and the emergent low energy effective field theory has the anisotropic scaling. -- Highlights: •The tight-binding model for graphene with varying hopping parameters is considered. •The emergent gravity and emergent gauge fields are derived. •For the case of the multilayer graphene we obtain the analogue of Horava gravity with anisotropic scaling.

  4. Dynamical 3-Space: Emergent Gravity

    E-Print Network [OSTI]

    Reginald T Cahill

    2011-02-16

    The laws of gravitation devised by Newton, and by Hilbert and Einstein, have failed many experimental and observational tests, namely the bore hole g anomaly, flat rotation curves for spiral galaxies, supermassive black hole mass spectrum, uniformly expanding universe, cosmic filaments, laboratory G measurements, galactic EM bending, precocious galaxy formation,.. The response has been the introduction of the new epicycles: ``dark matter", ``dark energy", and others. To understand gravity we must restart with the experimental discoveries by Galileo, and following a heuristic argument we are led to a uniquely determined theory of a dynamical 3-space. That 3-space exists has been missed from the beginning of physics, although it was 1st directly detected by Michelson and Morley in 1887. Uniquely generalising the quantum theory to include this dynamical 3-space we deduce the response of quantum matter and show that it results in a new account of gravity, and explains the above anomalies and others. The dynamical theory for this 3-space involves G, which determines the dissipation rate of space by matter, and alpha, which experiments and observation reveal to be the fine structure constant. For the 1st time we have a comprehensive account of space and matter and their interaction - gravity.

  5. Cosmological Hints of Modified Gravity ?

    E-Print Network [OSTI]

    Di Valentino, Eleonora; Silk, Joseph

    2015-01-01

    The recent measurements of Cosmic Microwave Background temperature and polarization anisotropies made by the Planck satellite have provided impressive confirmation of the $\\Lambda$CDM cosmological model. However interesting hints of slight deviations from $\\Lambda$CDM have been found, including a $95 \\%$ c.l. preference for a "modified gravity" structure formation scenario. In this paper we confirm the preference for a modified gravity scenario from Planck 2015 data, find that modified gravity solves the so-called $A_{lens}$ anomaly in the CMB angular spectrum, and constrains the amplitude of matter density fluctuations to $\\sigma_8=0.815_{-0.048}^{+0.032}$, in better agreement with weak lensing constraints. Moreover, we find a lower value for the reionization optical depth of $\\tau=0.059\\pm0.020$ (to be compared with the value of $\\tau= 0.079 \\pm 0.017$ obtained in the standard scenario), more consistent with recent optical and UV data. We check the stability of this result by considering possible degeneraci...

  6. "Table 2. Real Average Annual Coal Transportation Costs, By Primary...

    U.S. Energy Information Administration (EIA) Indexed Site

    Real Average Annual Coal Transportation Costs, By Primary Transport Mode and Supply Region" "(2013 dollars per ton)" "Coal Supply Region",2008,2009,2010,2011,2012,2013 "Railroad"...

  7. LOW-HIGH VALUES FOR PETROLEUM AVERAGE INVENTORY RANGES (MILLION...

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    ENERGY INFORMATION ADMINISTRATION LOW-HIGH VALUES FOR PETROLEUM AVERAGE INVENTORY RANGES (MILLION BARRELS) FILE UPDATED April 2004 Line Month Low High Number Product Name Geography...

  8. Entropic Motion in Loop Quantum Gravity

    E-Print Network [OSTI]

    J. Manuel Garcia-Islas

    2015-02-19

    Entropic forces result from an increase of the entropy of a thermodynamical physical system. It has been proposed that gravity is such a phenomenon and many articles have appeared on the literature concerning this problem. Loop quantum gravity has also considered such possibility. We propose a new method in loop quantum gravity which reproduces an entropic force. By considering the interaction between a fixed gravity state space and a particle state in loop quantum gravity, we show that it leads to a mathematical description of a random walk of such particle. The random walk in special situations, can be seen as an entropic motion in such a way that the particle will move towards a location where entropy increases. This may prove that such theory can reproduce gravity as it is expected.

  9. Simultaneous measurement of gravity acceleration and gravity gradient with an atom interferometer

    SciTech Connect (OSTI)

    Sorrentino, F.; Lien, Y.-H.; Rosi, G.; Tino, G. M.; Bertoldi, A.; Bodart, Q.; Cacciapuoti, L.; Angelis, M. de; Prevedelli, M.

    2012-09-10

    We demonstrate a method to measure the gravitational acceleration with a dual cloud atom interferometer; the use of simultaneous atom interferometers reduces the effect of seismic noise on the gravity measurement. At the same time, the apparatus is capable of accurate measurements of the vertical gravity gradient. The ability to determine the gravity acceleration and gravity gradient simultaneously and with the same instrument opens interesting perspectives in geophysical applications.

  10. The global warming signal is the average of

    E-Print Network [OSTI]

    Jones, Peter JS

    The global warming signal is the average of years 70-80 in the increasing CO2 run minus the average represent significant uncertainty in the global warming signal (Fig. 5). The differences at high latitudes, uncertainty in the isopycnal diffusivity causes uncertainty of up to 50% in the global warming signal

  11. Morgantown Slightly Exceeds National Average for Cost of Living

    E-Print Network [OSTI]

    Mohaghegh, Shahab

    (an index value of 100 reflects the national average). The index expresses the cost of living, health care, and miscellaneous goods and services. The index is designed to reflect the cost of living Relative to National Average by Category In Figure 2, we illustrate how the cost of living index has

  12. Gravity Data for west-central Colorado

    SciTech Connect (OSTI)

    Zehner, Richard

    2012-04-06

    Modeled Bouger Gravity data was extracted from the Pan American Center for Earth and Environmental Studies Gravity Database of the U.S. at http://irpsrvgis08.utep.edu/viewers/Flex/GravityMagnetic/GravityMagnetic_CyberShare/ on 2/29/2012. The downloaded text file was opened in an Excel spreadsheet. This spreadsheet data was then converted into an ESRI point shapefile in UTM Zone 13 NAD27 projection, showing location and gravity (in milligals). This data was then converted to grid and then contoured using ESRI Spatial Analyst. This dataset contains the original spreadsheet data, a point shapefile showing gravity station locations and Bouger gravity, and a line shapefile showing 1 milligal contours. Projection: UTM Zone 13 NAD27 Gravity Contour Shapefile Extent: West -108.366690 East -105.478730 North 40.932318 South 36.961606 Gravity Point Shapefile Extent: West -108.366692 East -105.478847 North 40.932361 South 36.961606 Data from From University of Texas: Pan American Center for Earth and Environmental Studies

  13. Gravity from the extension of spatial diffeomorphisms

    E-Print Network [OSTI]

    Szilard Farkas; Emil J. Martinec

    2010-02-24

    The possibility of the extension of spatial diffeomorphisms to a larger family of symmetries in a class of classical field theories is studied. The generator of the additional local symmetry contains a quadratic kinetic term and a potential term which can be a general (not necessarily local) functional of the metric. From the perspective of the foundation of Einstein's gravity our results are positive: The extended constraint algebra is either that of Einstein's gravity, or ultralocal gravity. If our goal is a simple modification of Einstein's gravity that for example makes it perturbatively renormalizable, as has recently been suggested, then our results show that there is no such theory within this class.

  14. Growth histories in bimetric massive gravity

    SciTech Connect (OSTI)

    Berg, Marcus; Buchberger, Igor; Enander, Jonas; Mörtsell, Edvard; Sjörs, Stefan E-mail: igor.buchberger@kau.se E-mail: edvard@fysik.su.se

    2012-12-01

    We perform cosmological perturbation theory in Hassan-Rosen bimetric gravity for general homogeneous and isotropic backgrounds. In the de Sitter approximation, we obtain decoupled sets of massless and massive scalar gravitational fluctuations. Matter perturbations then evolve like in Einstein gravity. We perturb the future de Sitter regime by the ratio of matter to dark energy, producing quasi-de Sitter space. In this more general setting the massive and massless fluctuations mix. We argue that in the quasi-de Sitter regime, the growth of structure in bimetric gravity differs from that of Einstein gravity.

  15. On the stability of gravity with Dirichlet walls

    E-Print Network [OSTI]

    Andrade, T; Kelly, WR; Marolf, D; Santos, JE

    2015-01-01

    Dirichlet problem : Fluid/Gravity on cut-off surfaces, JHEPWilsonian Approach to Fluid/Gravity Duality, JHEP 1103 (and other theories of gravity, Phys.Rev. D61 (2000) 084027 [

  16. Gravity monitoring of CO2 movement during sequestration: Model studies

    E-Print Network [OSTI]

    Gasperikova, E.

    2008-01-01

    right. Figure 14: Surface gravity response (?Gal) for theAbsolute and relative gravity integration for high precision2003, Seafloor Micro-gravity Survey of the Sleipner CO 2

  17. A SEA FLOOR GRAVITY SURVEY OF THE SLEIPNER FIELD TO MONITOR CO2 MIGRATION

    SciTech Connect (OSTI)

    Mark Zumberge; Scott Nooner; Glenn Sasagawa

    2004-05-19

    Since 1996, excess CO{sub 2} from the Sleipner natural gas field has been sequestered and injected underground into a porous saline aquifer 1000 m below the seafloor. In 2002, we carried out a high precision micro-gravity survey on the seafloor in order to monitor the injected CO{sub 2}. A repeatability of 5 {micro}Gal in the station averages was observed. This is considerably better than pre-survey expectations. These data will serve as the baseline for time-lapse gravity monitoring of the Sleipner CO{sub 2} injection site. A repeat survey has been scheduled for the summer of 2005. This report covers 9/19/03 to 3/18/04. During this time, significant advancement in the 3-D gravity forward modeling code was made. Testing of the numerical accuracy of the code was undertaken using both a sheet of mass and a frustum of a cone for test cases. These were chosen because of our ability to do an analytic calculation of gravity for comparison. Tests were also done to determine the feasibility of using point mass approximations rather than cuboids for the forward modeling code. After determining that the point mass approximation is sufficient (and over six times faster computationally), several CO{sub 2} models were constructed and the time-lapse gravity signal was calculated from each. From these models, we expect to see a gravity change ranging from 3-16 {micro}Gal/year, depending on reservoir conditions and CO{sub 2} geometry. While more detailed modeling needs to be completed, these initial results show that we may be able to learn a great deal about the state of the CO{sub 2} from the time-lapse gravity results. Also, in December of 2003, we presented at the annual AGU meeting in San Francisco.

  18. Counterterms in Massive Gravity Theory

    E-Print Network [OSTI]

    Cao, Li-Ming

    2015-01-01

    We derived local boundary counterterms in massive gravity theory with a negative cosmological constant in four dimensions. With these counterterms at hand we analyzed the properties of the boundary field theory in the context of AdS/CFT duality by calculating the boundary stress energy tensor. The calculation shows that the boundary stress energy tensor is conserved, and momentum dissipation might occur on the level of linear response only. We also calculated the thermodynamic quantities and the boundary stress energy tensor for a specific type of solutions. The thermodynamic potentials agree with the results of literature up to some constants which can be removed by adding finite counterterms.

  19. A new quasidilaton theory of massive gravity (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    A new quasidilaton theory of massive gravity Citation Details In-Document Search Title: A new quasidilaton theory of massive gravity We present a new quasidilaton theory of...

  20. Ground Gravity Survey At Dixie Valley Geothermal Area (Allis...

    Open Energy Info (EERE)

    Ground Gravity Survey At Dixie Valley Geothermal Area (Allis, Et Al., 2000) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey...

  1. Ground Gravity Survey At Roosevelt Hot Springs Geothermal Area...

    Open Energy Info (EERE)

    Ground Gravity Survey At Roosevelt Hot Springs Geothermal Area (Faulder, 1991) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity...

  2. Hamiltonian analysis of self-dual gauge gravity

    E-Print Network [OSTI]

    Steven Kerr

    2015-04-15

    The Hamiltonian analysis of the self-dual gauge gravity theory is carried out. The resulting canonical structure is equivalent to that of self-dual gravity.

  3. Ground Gravity Survey At Neal Hot Springs Geothermal Area (Colwell...

    Open Energy Info (EERE)

    Ground Gravity Survey At Neal Hot Springs Geothermal Area (Colwell, Et Al., 2012) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity...

  4. Ground Gravity Survey At Lake City Hot Springs Area (Warpinski...

    Open Energy Info (EERE)

    Ground Gravity Survey At Lake City Hot Springs Area (Warpinski, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity...

  5. Ground Gravity Survey At Under Steamboat Springs Area (Warpinski...

    Open Energy Info (EERE)

    Ground Gravity Survey At Under Steamboat Springs Area (Warpinski, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity...

  6. Ground Gravity Survey At Kilauea East Rift Geothermal Area (FURUMOTO...

    Open Energy Info (EERE)

    Ground Gravity Survey At Kilauea East Rift Geothermal Area (FURUMOTO, 1976) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey...

  7. Ground Gravity Survey At Kilauea East Rift Geothermal Area (Leslie...

    Open Energy Info (EERE)

    Ground Gravity Survey At Kilauea East Rift Geothermal Area (Leslie, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity...

  8. Ground Gravity Survey At Kilauea East Rift Geothermal Area (Broyles...

    Open Energy Info (EERE)

    Ground Gravity Survey At Kilauea East Rift Geothermal Area (Broyles, Et Al., 1979) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity...

  9. Integration of Full Tensor Gravity and ZTEM Passive Low Frequency...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Full Tensor Gravity and ZTEM Passive Low Frequency EM Instruments for Simultaneous Data Acquisition Integration of Full Tensor Gravity and ZTEM Passive Low Frequency EM Instruments...

  10. PLASMA MEMBRANE GLYCOPKOTEINS OF MATURE AND IMMA'I`UKE DRONE HONEY BEE (Apis mellifera I_) SPERMATOZOA: LECI'IN-BINDING AS SEEN BY LIGHT AND ELECTRON

    E-Print Network [OSTI]

    Zaragoza, Universidad de

    ELSEVIER PLASMA MEMBRANE GLYCOPKOTEINS OF MATURE AND IMMA'I`UKE DRONE HONEY BEE (Apis mellifera I in spermatozoa of A isa drones, may play a role in oocyte-spermatozoon recognition. We studied the distribution of the glycoproteins and changes in their composition associated with maturation of the drones, using lectin binding

  11. Gravity in Complex Hermitian Space-Time

    E-Print Network [OSTI]

    Ali H. Chamseddine

    2006-10-09

    A generalized theory unifying gravity with electromagnetism was proposed by Einstein in 1945. He considered a Hermitian metric on a real space-time. In this work we review Einstein's idea and generalize it further to consider gravity in a complex Hermitian space-time.

  12. Horava-Lifshitz gravity with detailed balance

    E-Print Network [OSTI]

    Daniele Vernieri; Thomas P. Sotiriou

    2012-12-18

    Horava-Lifshitz gravity with "detailed balance" but without the projectability assumption is discussed. It is shown that detailed balance is quite efficient in limiting the proliferation of couplings in Horava-Lifshitz gravity, and that its implementation without the projectability assumption leads to a theory with sensible dynamics. However, the (bare) cosmological constant is restricted to be large and negative.

  13. Gravity Capillary Standing Water Waves Pietro Baldi

    E-Print Network [OSTI]

    Thomann, Laurent

    Gravity Capillary Standing Water Waves Pietro Baldi Universit`a di Napoli Federico II Joint work with Thomas Alazard (ENS Paris) Pienza, 29 October 2014 Pietro Baldi Gravity Capillary Standing Water Waves construct small amplitude, standing solutions of Sobolev reg. (standing := periodic in time and space

  14. Fact #870: April 27, 2015 Corporate Average Fuel Economy Progress...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Progress, 1978-2014 The Corporate Average Fuel Economy (CAFE) is the sales-weighted harmonic mean fuel economy of a manufacturer's fleet of new cars or light trucks in a certain...

  15. Fact #624: May 24, 2010 Corporate Average Fuel Economy Standards...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    by the fleet of each manufacturer will be determined by computing the sales-weighted harmonic average of the targets applicable to each of the manufacturer's passenger cars and...

  16. On the Choice of Average Solar Zenith Angle

    E-Print Network [OSTI]

    Cronin, Timothy W.

    Idealized climate modeling studies often choose to neglect spatiotemporal variations in solar radiation, but doing so comes with an important decision about how to average solar radiation in space and time. Since both ...

  17. Does anyone have access to 2012 average residential rates by...

    Open Energy Info (EERE)

    Does anyone have access to 2012 average residential rates by utility company? I'm seeing an inconsistency between the OpenEI website and EIA 861 data set. Home > Groups > Utility...

  18. INDIVIDUAL REFORM ELEMENTS .63Average course exam score

    E-Print Network [OSTI]

    Colorado at Boulder, University of

    INDIVIDUAL REFORM ELEMENTS .63Average course exam score .11In class clicker score .02Lecture: · Correlations with effort/curricular elements are positive but not high, indicating no individual course reform

  19. Fact #889: September 7, 2015 Average Diesel Price Lower than...

    Broader source: Energy.gov (indexed) [DOE]

    Average Diesel Price Lower than Gasoline for the First Time in Six Years fotw889web.xlsx More Documents & Publications Fact 859 February 9, 2015 Excess Supply is the Most Recent...

  20. Bounded Parameter Markov Decision Processes with Average Reward Criterion

    E-Print Network [OSTI]

    Tewari, Ambuj

    Bounded Parameter Markov Decision Processes with Average Reward Criterion Ambuj Tewari1 and Peter L, pp. 263­277, 2007. c Springer-Verlag Berlin Heidelberg 2007 #12;264 A. Tewari and P.L. Bartlett

  1. Naked singularities and quantum gravity

    SciTech Connect (OSTI)

    Harada, Tomohiro; Iguchi, Hideo; Nakao, Ken-ichi; Singh, T. P.; Tanaka, Takahiro; Vaz, Cenalo

    2001-08-15

    There are known models of spherical gravitational collapse in which the collapse ends in a naked shell-focusing singularity for some initial data. If a massless scalar field is quantized on the classical background provided by such a star, it is found that the outgoing quantum flux of the scalar field diverges in the approach to the Cauchy horizon. We argue that the semiclassical approximation (i.e., quantum field theory on a classical curved background) used in these analyses ceases to be valid about one Planck time before the epoch of naked singularity formation, because by then the curvature in the central region of the star reaches the Planck scale. It is shown that during the epoch in which the semiclassical approximation is valid, the total emitted energy is about one Planck unit, and is not divergent. We also argue that back reaction in this model does not become important so long as gravity can be treated classically. It follows that the further evolution of the star will be determined by quantum gravitational effects, and without invoking quantum gravity it is not possible to say whether the star radiates away on a short time scale or settles down into a black hole state.

  2. Averaged null energy condition violation in a conformally flat spacetime

    SciTech Connect (OSTI)

    Urban, Douglas; Olum, Ken D.

    2010-01-15

    We show that the averaged null energy condition can be violated by a conformally coupled scalar field in a conformally flat spacetime in 3+1 dimensions. The violation is dependent on the quantum state and can be made as large as desired. It does not arise from the presence of anomalies, although anomalous violations are also possible. Since all geodesics in conformally flat spacetimes are achronal, the achronal averaged null energy condition is likewise violated.

  3. Flavor Physics Data from the Heavy Flavor Averaging Group (HFAG)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The Heavy Flavor Averaging Group (HFAG) was established at the May 2002 Flavor Physics and CP Violation Conference in Philadelphia, and continues the LEP Heavy Flavor Steering Group's tradition of providing regular updates to the world averages of heavy flavor quantities. Data are provided by six subgroups that each focus on a different set of heavy flavor measurements: B lifetimes and oscillation parameters, Semi-leptonic B decays, Rare B decays, Unitarity triangle parameters, B decays to charm final states, and Charm Physics.

  4. Solar System constraints to nonminimally coupled gravity

    E-Print Network [OSTI]

    Orfeu Bertolami; Riccardo March; Jorge Páramos

    2013-06-05

    We extend the analysis of Chiba, Smith and Erickcek \\cite{CSE} of Solar System constraints on $f(R)$ gravity to a class of nonminimally coupled (NMC) theories of gravity. These generalize $f(R)$ theories by replacing the action functional of General Relativity (GR) with a more general form involving two functions $f^1(R)$ and $f^2(R)$ of the Ricci scalar curvature $R$. While the function $f^1(R)$ is a nonlinear term in the action, analogous to $f(R)$ gravity, the function $f^2(R)$ yields a NMC between the matter Lagrangian density $\\LL_m$ and the scalar curvature. The developed method allows for obtaining constraints on the admissible classes of functions $f^1(R)$ and $f^2(R)$, by requiring that predictions of NMC gravity are compatible with Solar System tests of gravity. We apply this method to a NMC model which accounts for the observed accelerated expansion of the Universe.

  5. The Necessity of Quantizing Gravity

    E-Print Network [OSTI]

    Adelman, Jeremy

    2015-01-01

    The Eppley Hannah thought experiment is often cited as justification for attempts by theorists to develop a complete, consistent theory of quantum gravity. A modification of the earlier "Heisenberg microscope" argument for the necessity of quantized light, the Eppley-Hannah thought experiment purports to show that purely classical gravitational waves would either not conserve energy or else allow for violations of the uncertainty principle. However, several subsequent papers have cast doubt as to the validity of the Eppley-Hannah argument. In this paper, we attempt to resurrect the Eppley-Hannah thought experiment by modifying the original argument in such a manner as to render it immune to the present criticisms levied against it.

  6. A parametrix for quantum gravity?

    E-Print Network [OSTI]

    Esposito, Giampiero

    2015-01-01

    In the sixties, DeWitt discovered that the advanced and retarded Green functions of the wave operator on metric perturbations in the de Donder gauge make it possible to define classical Poisson brackets on the space of functionals that are invariant under the action of the full diffeomorphism group of spacetime. He therefore tried to exploit this property to define invariant commutators for the quantized gravitational field, but the operator counterpart of such classical Poisson brackets turned out to be a hard task. On the other hand, the mathematical literature studies often an approximate inverse, the parametrix, which is, strictly, a distribution. We here suggest that such a construction might be exploited in canonical quantum gravity. We begin with the simplest case, i.e. fundamental solution and parametrix for the linear, scalar wave operator; the next step are tensor wave equations, again for linear theory, e.g. Maxwell theory in curved spacetime. Last, the nonlinear Einstein equations are studied, rel...

  7. Dimensional Reduction in Quantum Gravity

    E-Print Network [OSTI]

    G. 't Hooft

    2009-03-20

    The requirement that physical phenomena associated with gravitational collapse should be duly reconciled with the postulates of quantum mechanics implies that at a Planckian scale our world is not 3+1 dimensional. Rather, the observable degrees of freedom can best be described as if they were Boolean variables defined on a two-dimensional lattice, evolving with time. This observation, deduced from not much more than unitarity, entropy and counting arguments, implies severe restrictions on possible models of quantum gravity. Using cellular automata as an example it is argued that this dimensional reduction implies more constraints than the freedom we have in constructing models. This is the main reason why so-far no completely consistent mathematical models of quantum black holes have been found. Essay dedicated to Abdus Salam.

  8. Testing Gravity Using Dwarf Stars

    E-Print Network [OSTI]

    Sakstein, Jeremy

    2015-01-01

    Generic scalar-tensor theories of gravity predict deviations from Newtonian physics inside astrophysical bodies. In this paper, we point out that low mass stellar objects, red and brown dwarf stars, are excellent probes of these theories. We calculate two important and potentially observable quantities: the radius of brown dwarfs and the minimum mass for hydrogen burning in red dwarfs. The brown dwarf radius can differ significantly from the GR prediction and upcoming surveys that probe the mass-radius relation for stars with masses $hydrogen burning can be larger than several presently observed Red Dwarf stars. This places a new and extremely stringent constraint on the parameters that appear in the effective field theory of dark energy and rules out several well-studied dark energy models.

  9. Testing Gravity Using Dwarf Stars

    E-Print Network [OSTI]

    Jeremy Sakstein

    2015-11-05

    Generic scalar-tensor theories of gravity predict deviations from Newtonian physics inside astrophysical bodies. In this paper, we point out that low mass stellar objects, red and brown dwarf stars, are excellent probes of these theories. We calculate two important and potentially observable quantities: the radius of brown dwarfs and the minimum mass for hydrogen burning in red dwarfs. The brown dwarf radius can differ significantly from the GR prediction and upcoming surveys that probe the mass-radius relation for stars with masses $hydrogen burning can be larger than several presently observed Red Dwarf stars. This places a new and extremely stringent constraint on the parameters that appear in the effective field theory of dark energy and rules out several well-studied dark energy models.

  10. Ising-link Quantum Gravity

    E-Print Network [OSTI]

    Tom Fleming; Mark Gross; Ray Renken

    1994-01-04

    We define a simplified version of Regge quantum gravity where the link lengths can take on only two possible values, both always compatible with the triangle inequalities. This is therefore equivalent to a model of Ising spins living on the links of a regular lattice with somewhat complicated, yet local interactions. The measure corresponds to the natural sum over all 2^links configurations, and numerical simulations can be efficiently implemented by means of look-up tables. In three dimensions we find a peak in the ``curvature susceptibility'' which grows with increasing system size. However, the value of the corresponding critical exponent as well as the behavior of the curvature at the transition differ from that found by Hamber and Williams for the Regge theory with continuously varying link lengths.

  11. Emergent Horava gravity in graphene

    E-Print Network [OSTI]

    G. E. Volovik; M. A. Zubkov

    2013-07-07

    First of all, we reconsider the tight - binding model of monolayer graphene, in which the variations of the hopping parameters are allowed. We demonstrate that the emergent 2D Weitzenbock geometry as well as the emergent U(1) gauge field appear. The emergent gauge field is equal to the linear combination of the components of the zweibein. Therefore, we actually deal with the gauge fixed version of the emergent 2+1 D teleparallel gravity. In particular, we work out the case, when the variations of the hopping parameters are due to the elastic deformations, and relate the elastic deformations with the emergent zweibein. Next, we investigate the tight - binding model with the varying intralayer hopping parameters for the multilayer graphene with the ABC stacking. In this case the emergent 2D Weitzenbock geometry and the emergent U(1) gauge field appear as well, the emergent low energy effective field theory has the anisotropic scaling.

  12. Gravity as BF theory plus potential

    E-Print Network [OSTI]

    Kirill Krasnov

    2009-07-23

    Spin foam models of quantum gravity are based on Plebanski's formulation of general relativity as a constrained BF theory. We give an alternative formulation of gravity as BF theory plus a certain potential term for the B-field. When the potential is taken to be infinitely steep one recovers general relativity. For a generic potential the theory still describes gravity in that it propagates just two graviton polarizations. The arising class of theories is of the type amenable to spin foam quantization methods, and, we argue, may allow one to come to terms with renormalization in the spin foam context.

  13. Gauge Gravity and Space-Time

    E-Print Network [OSTI]

    Ning Wu

    2012-07-11

    When we discuss problems on gravity, we can not avoid some fundamental physical problems, such as space-time, inertia, and inertial reference frame. The goal of this paper is to discuss the logic system of gravity theory and the problems of space-time, inertia, and inertial reference frame. The goal of this paper is to set up the theory on space-time in gauge theory of gravity. Based on this theory, it is possible for human kind to manipulate physical space-time on earth, and produce a machine which can physically prolong human's lifetime.

  14. Surface gravities for non-Killing horizons

    E-Print Network [OSTI]

    Cropp, Bethan; Visser, Matt

    2013-01-01

    There are many logically and computationally distinct characterizations of the surface gravity of a horizon, just as there are many logically rather distinct notions of horizon. Fortunately, in standard general relativity, for stationary horizons, most of these characterizations are degenerate. However, in modified gravity, or in analogue spacetimes, horizons may be non-Killing or even non-null, and hence these degeneracies can be lifted. We present a brief overview of the key issues, specifically focusing on horizons in analogue spacetimes and universal horizons in modified gravity.

  15. Status of Horava gravity: A personal perspective

    E-Print Network [OSTI]

    Visser, Matt

    2011-01-01

    Horava gravity is a relatively recent (Jan 2009) idea in theoretical physics for trying to develop a quantum field theory of gravity. It is not a string theory, nor loop quantum gravity, but is instead a traditional quantum field theory that breaks Lorentz invariance at ultra-high (presumably trans-Planckian) energies, while retaining approximate Lorentz invariance at low and medium (sub-Planckian) energies. The challenge is to keep the Lorentz symmetry breaking controlled and small - small enough to be compatible with experiment. I will give a very general overview of what is going on in this field, paying particular attention to the disturbing role of the scalar graviton.

  16. High average power scaleable thin-disk laser

    DOE Patents [OSTI]

    Beach, Raymond J. (Livermore, CA); Honea, Eric C. (Sunol, CA); Bibeau, Camille (Dublin, CA); Payne, Stephen A. (Castro Valley, CA); Powell, Howard (Livermore, CA); Krupke, William F. (Pleasanton, CA); Sutton, Steven B. (Manteca, CA)

    2002-01-01

    Using a thin disk laser gain element with an undoped cap layer enables the scaling of lasers to extremely high average output power values. Ordinarily, the power scaling of such thin disk lasers is limited by the deleterious effects of amplified spontaneous emission. By using an undoped cap layer diffusion bonded to the thin disk, the onset of amplified spontaneous emission does not occur as readily as if no cap layer is used, and much larger transverse thin disks can be effectively used as laser gain elements. This invention can be used as a high average power laser for material processing applications as well as for weapon and air defense applications.

  17. Gravity Waves in a Horizontal Shear Flow. Part II: Interaction between Gravity Waves and Potential Vorticity Perturbations

    E-Print Network [OSTI]

    Farrell, Brian F.

    Gravity Waves in a Horizontal Shear Flow. Part II: Interaction between Gravity Waves and Potential perturbations and propagating internal gravity waves in a horizon- tally sheared zonal flow is investigated. In the strong stratification limit, an initial vorticity perturbation weakly excites two propagating gravity

  18. The High Average Power Laser Program 15th HAPL meeting

    E-Print Network [OSTI]

    , 2006 #12;2 The HAPL team is developing the science, technology and architecture needed for a laser1 The High Average Power Laser Program 15th HAPL meeting Aug 8 & 9, 2006 General Atomics Scientific Inst 16. Optiswitch Technology 17. ESLI Electricity Generator Electricity Generator Reaction

  19. FOCI RESEARCH BENEFITS FISHERIES MANAGEMENT 1993 Recruitment Forecast -Average

    E-Print Network [OSTI]

    Marine Fisheries Service (NMFS) advises the North Pacific Fisheries Management Council using a "stock data but addresses the autocorrelation of recruitment. In addition, it directly predicts recruitment to average 1991 year class, and a strong 1992 year class. In 1993 the transfer function model predicted

  20. Parity-violating anomalies and the stationarity of stochastic averages

    SciTech Connect (OSTI)

    Reuter, M.

    1988-01-15

    Within the framework of stochastic quantization the parity-violating anomalies in odd space-time dimensions are derived from the asymptotic stationarity of the stochastic average of a certain fermion bilinear. Contrary to earlier attempts, this method yields the correct anomalies for both massive and massless fermions.

  1. Probabilistic Wind Vector Forecasting Using Ensembles and Bayesian Model Averaging

    E-Print Network [OSTI]

    Raftery, Adrian

    Probabilistic Wind Vector Forecasting Using Ensembles and Bayesian Model Averaging J. MCLEAN 2011, in final form 26 May 2012) ABSTRACT Probabilistic forecasts of wind vectors are becoming critical with univariate quantities, statistical approaches to wind vector forecasting must be based on bivariate

  2. Probabilistic Wind Speed Forecasting Using Ensembles and Bayesian Model Averaging

    E-Print Network [OSTI]

    Raftery, Adrian

    Probabilistic Wind Speed Forecasting Using Ensembles and Bayesian Model Averaging J. Mc in the context of wind power, where under- forecasting and overforecasting carry different financial penal- ties, calibrated and sharp probabilistic forecasts can help to make wind power a more financially competitive alter

  3. Fact #693: September 19, 2011 Average Vehicle Footprint for Cars...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    information below. Supporting Information Average Vehicle Footprint, 2008-2010 Model Year Car Light Truck All Light Vehicles 2008 45.4 53.0 49.0 2009 45.2 52.7 48.2 2010 45.2 54.0...

  4. Prediction in moving average processes Anton Schick and Wolfgang Wefelmeyer

    E-Print Network [OSTI]

    Wefelmeyer, Wolfgang

    Prediction in moving average processes Anton Schick and Wolfgang Wefelmeyer Abstract(y + (x1, . . . , xr)) dF(y) The research of A. Schick was partially supported by NSF Grant DMS0405791. 1 #12;2 ANTON SCHICK AND WOLFGANG WEFELMEYER can be estimated at the "parametric" root-n rate

  5. Optimal Control with Weighted Average Costs and Temporal Logic Specifications

    E-Print Network [OSTI]

    Murray, Richard M.

    Optimal Control with Weighted Average Costs and Temporal Logic Specifications Eric M. Wolff Control and Dynamical Systems California Institute of Technology Pasadena, California 91125 Email: ewolff@caltech.edu Ufuk Topcu Control and Dynamical Systems California Institute of Technology Pasadena, California 91125

  6. Antimatter-Gravity Couplings, and Lorentz Symmetry

    E-Print Network [OSTI]

    Jay D. Tasson

    2015-01-27

    Implications of possible CPT and Lorentz violation for antimatter-gravity experiments as well as other antimatter tests are considered in the context of the general field-theory-based framework of the Standard-Model Extension (SME).

  7. Asymptotic safety of gravity-matter systems

    E-Print Network [OSTI]

    Meibohm, Jan; Reichert, Manuel

    2015-01-01

    We study the ultraviolet stability of gravity-matter systems for general numbers of minimally coupled scalars and fermions. This is done within the functional renormalisation group setup put forward in \\cite{Christiansen:2015rva} for pure gravity. It includes full dynamical propagators and a genuine dynamical Newton's coupling, which is extracted from the graviton three-point function. We find ultraviolet stability of general gravity-fermion systems. Gravity-scalar systems are also found to be ultraviolet stable within validity bounds for the chosen generic class of regulators, based on the size of the anomalous dimension. Remarkably, the ultraviolet fixed points for the dynamical couplings are found to be significantly different from those of their associated background counterparts, once matter fields are included. In summary, the asymptotic safety scenario does not put constraints on the matter content of the theory within the validity bounds for the chosen generic class of regulators.

  8. Quantum gravity and renormalization: The tensor track

    SciTech Connect (OSTI)

    Rivasseau, Vincent

    2012-06-27

    We propose a new program to quantize and renormalize gravity based on recent progress on the analysis of large random tensors. We compare it briefly with other existing approaches.

  9. Energy conditions in f(R)-gravity

    E-Print Network [OSTI]

    J. Santos; J. S. Alcaniz; M. J. Reboucas; F. C. Carvalho

    2007-09-06

    In order to shed some light on the current discussion about f(R)-gravity theories we derive and discuss the bounds imposed by the energy conditions on a general f(R) functional form. The null and strong energy conditions in this framework are derived from the Raychaudhuri's equation along with the requirement that gravity is attractive, whereas the weak and dominant energy conditions are stated from a comparison with the energy conditions that can be obtained in a direct approach via an effective energy-momentum tensor for f(R)-gravity. As a concrete application of the energy conditions to locally homogeneous and isotropic f(R)-cosmology, the recent estimated values of the deceleration and jerk parameters are used to examine the bounds from the weak energy condition on the parameters of two families of f(R)-gravity theories.

  10. Test particle motion in modified gravity theories

    E-Print Network [OSTI]

    Mahmood Roshan

    2013-02-05

    We derive the equations of motion of an electrically neutral test particle for modified gravity theories in which the covariant divergence of the ordinary matter energy-momentum tensor dose not vanish (i.e. $\

  11. A new vacuum for Loop Quantum Gravity

    E-Print Network [OSTI]

    Bianca Dittrich; Marc Geiller

    2015-05-05

    We construct a new vacuum for loop quantum gravity, which is dual to the Ashtekar-Lewandowski vacuum. Because it is based on BF theory, this new vacuum is physical for $(2+1)$-dimensional gravity, and much closer to the spirit of spin foam quantization in general. To construct this new vacuum and the associated representation of quantum observables, we introduce a modified holonomy-flux algebra which is cylindrically consistent with respect to the notion of refinement by time evolution suggested in [1]. This supports the proposal for a construction of a physical vacuum made in [1,2], also for $(3+1)$-dimensional gravity. We expect that the vacuum introduced here will facilitate the extraction of large scale physics and cosmological predictions from loop quantum gravity.

  12. Gravity waves from vortex dipoles and jets 

    E-Print Network [OSTI]

    Wang, Shuguang

    2009-05-15

    The dissertation first investigates gravity wave generation and propagation from jets within idealized vortex dipoles using a nonhydrostatic mesoscale model. Several initially balanced and localized jets induced by vortex dipoles are examined here...

  13. Primordial Density Fluctuations in Phase Coupling Gravity

    E-Print Network [OSTI]

    C. E. M. Batista; M. Schiffer

    1996-01-10

    In this paper we study the evolution of density perturbations in the framework of Phase Coupling Gravity theory at the very early universe. We show that these perturbation display an exponential-like behaviour.

  14. Oblique reflections of internal gravity wave beams

    E-Print Network [OSTI]

    Karimi, Hussain H. (Hussain Habibullah)

    2012-01-01

    We study nonlinear effects in reflections of internal gravity wave beams in a continuously stratified liquid which are incident upon a uniform slope at an oblique angle. Wave motion in a stratified fluid medium is unique ...

  15. Emergence in Holographic Scenarios for Gravity

    E-Print Network [OSTI]

    Dennis Dieks; Jeroen van Dongen; Sebastian de Haro

    2015-09-10

    'Holographic' relations between theories have become an important theme in quantum gravity research. These relations entail that a theory without gravity is equivalent to a gravitational theory with an extra spatial dimension. The idea of holography was first proposed in 1993 by Gerard 't Hooft on the basis of his studies of evaporating black holes. Soon afterwards the holographic 'AdS/CFT' duality was introduced, which since has been intensively studied in the string theory community and beyond. Recently, Erik Verlinde has proposed that even Newton's law of gravitation can be related holographically to the `thermodynamics of information' on screens. We discuss these scenarios, with special attention to the status of the holographic relation in them and to the question of whether they make gravity and spacetime emergent. We conclude that only Verlinde's scheme straightfowardly instantiates emergence. However, assuming a non-standard interpretation of AdS/CFT may create room for the emergence of spacetime and gravity there as well.

  16. Brane worlds in gravity with auxiliary fields

    E-Print Network [OSTI]

    Bin Guo; Yu-Xiao Liu; Ke Yang

    2015-03-11

    Recently, Pani, Sotiriou, and Vernieri explored a new theory of gravity by adding nondynamical fields, i.e., gravity with auxiliary fields [Phys. Rev. D 88, 121502(R) (2013)]. In this gravity theory, higher-order derivatives of matter fields generically appear in the field equations. In this paper we extend this theory to any dimensions and discuss the thick braneworld model in five dimensions. Domain wall solutions are obtained numerically. The stability of the brane system under the tensor perturbation is analyzed. We find that the system is stable under the tensor perturbation and the gravity zero mode is localized on the brane. Therefore, the four-dimensional Newtonian potential can be realized on the brane.

  17. Gravity waves from cosmic bubble collisions

    SciTech Connect (OSTI)

    Salem, Michael P.; Saraswat, Prashant; Shaghoulian, Edgar E-mail: ps88@stanford.edu

    2013-02-01

    Our local Hubble volume might be contained within a bubble that nucleated in a false vacuum with only two large spatial dimensions. We study bubble collisions in this scenario and find that they generate gravity waves, which are made possible in this context by the reduced symmetry of the global geometry. These gravity waves would produce B-mode polarization in the cosmic microwave background, which could in principle dominate over the inflationary background.

  18. Green's Functions in Perturbative Quantum Gravity

    E-Print Network [OSTI]

    Sudhaker Upadhyay; Bhabani Prasad Mandal

    2015-04-03

    We show that the Green's functions in non-linear gauge in the theory of perturbative quantum gravity is expressed as a series in terms of those in linear gauges. This formulation is also holds for operator Green's functions. We further derive the explicit relation between the Green's functions in the theory of perturbative quantum gravity in a pair of arbitary gauges. This process involves some sort of modified FFBRST transformations which is derivable from infinitesimal field-dependent BRST transformations.

  19. Anisotropic induced gravity and inflationary universe

    E-Print Network [OSTI]

    W. F. Kao

    2006-12-09

    Existence and stability analysis of the Kantowski-Sachs type universe in a higher derivative induced gravity theory is studied in details. Existence of one stable mode and one unstable mode is shown to be in favor of the inflationary universe. As a result, the de Sitter background can be made to be stable against anisotropic perturbations with proper constraints imposed on the coupling constants of the induced gravity model.

  20. An Analysis of Air Passenger Average Trip Lengths and Fare Levels in US Domestic Markets

    E-Print Network [OSTI]

    Huang, Sheng-Chen Alex

    2000-01-01

    California at Berkeley An Analysis of Air Passenger AverageCalifornia at Berkeley An Analysis of Air Passenger Average

  1. Analogue gravity in hyperbolic metamaterials

    E-Print Network [OSTI]

    Igor I. Smolyaninov

    2013-09-09

    Sub-wavelength confinement of light in nonlinear hyperbolic metamaterials due to formation of spatial solitons has attracted much recent attention because of its seemingly counter-intuitive behavior. In order to achieve self-focusing in a hyperbolic wire medium, a nonlinear self-defocusing Kerr medium must be used as a dielectric host. Here we demonstrate that this behavior finds natural explanation in terms of analogue gravity. Wave equation describing propagation of extraordinary light inside hyperbolic metamaterials exhibits 2+1 dimensional Lorentz symmetry. The role of time in the corresponding effective 3D Minkowski spacetime is played by the spatial coordinate aligned with the optical axis of the metamaterial. Nonlinear optical Kerr effect bends this spacetime resulting in effective gravitational force between extraordinary photons. In order for the effective gravitational constant to be positive, negative self-defocusing Kerr medium must be used as a host. If gravitational self-interaction is strong enough, spatial soliton may collapse into a black hole analogue.

  2. Measuring antimatter gravity with muonium

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kaplan, Daniel M.; Kirch, Klaus; Mancini, Derrick; Phillips, James D.; Phillips, Thomas J.; Roberts, Thomas J.; Terry, Jeff; Bravina, L.; Foka, Y.; Kabana, S.

    2015-05-29

    The gravitational acceleration of antimatter, ¯g, has never been directly measured and could bear importantly on our understanding of gravity, the possible existence of a fifth force, and the nature and early history of the universe. Only two avenues for such a measurement appear to be feasible: antihydrogen and muonium. The muonium measurement requires a novel, monoenergetic, low-velocity, horizontal muonium beam directed at an atom interferometer. The precision three-grating interferometer can be produced in silicon nitride or ultrananocrystalline diamond using state-of-the-art nanofabrication. The required precision alignment and calibration at the picometer level also appear to be feasible. With 100 nmmore »grating pitch, a 10% measurement of ¯g can be made using some months of surface-muon beam time, and a 1% or better measurement with a correspondingly larger exposure. This could constitute the first gravitational measurement of leptonic matter, of 2nd-generation matter and, possibly, the first measurement of the gravitational acceleration of antimatter.« less

  3. Measuring antimatter gravity with muonium

    SciTech Connect (OSTI)

    Kaplan, Daniel M.; Kirch, Klaus; Mancini, Derrick; Phillips, James D.; Phillips, Thomas J.; Roberts, Thomas J.; Terry, Jeff; Bravina, L.; Foka, Y.; Kabana, S.

    2015-05-29

    The gravitational acceleration of antimatter, ¯g, has never been directly measured and could bear importantly on our understanding of gravity, the possible existence of a fifth force, and the nature and early history of the universe. Only two avenues for such a measurement appear to be feasible: antihydrogen and muonium. The muonium measurement requires a novel, monoenergetic, low-velocity, horizontal muonium beam directed at an atom interferometer. The precision three-grating interferometer can be produced in silicon nitride or ultrananocrystalline diamond using state-of-the-art nanofabrication. The required precision alignment and calibration at the picometer level also appear to be feasible. With 100 nm grating pitch, a 10% measurement of ¯g can be made using some months of surface-muon beam time, and a 1% or better measurement with a correspondingly larger exposure. This could constitute the first gravitational measurement of leptonic matter, of 2nd-generation matter and, possibly, the first measurement of the gravitational acceleration of antimatter.

  4. Nonderivative modified gravity: a classification

    SciTech Connect (OSTI)

    Comelli, D.; Nesti, F.; Pilo, L. E-mail: fabrizio.nesti@irb.hr

    2014-11-01

    We analyze the theories of gravity modified by a generic nonderivative potential built from the metric, under the minimal requirement of unbroken spatial rotations. Using the canonical analysis, we classify the potentials V according to the number of degrees of freedom (DoF) that propagate at the nonperturbative level. We then compare the nonperturbative results with the perturbative DoF propagating around Minkowski and FRW backgrounds. A generic V implies 6 propagating DoF at the non-perturbative level, with a ghost on Minkowski background. There exist potentials which propagate 5 DoF, as already studied in previous works. Here, no V with unbroken rotational invariance admitting 4 DoF is found. Theories with 3 DoF turn out to be strongly coupled on Minkowski background. Finally, potentials with only the 2 DoF of a massive graviton exist. Their effect on cosmology is simply equivalent to a cosmological constant. Potentials with 2 or 5 DoF and explicit time dependence appear to be a further viable possibility.

  5. Bimetric gravity and dark matter

    E-Print Network [OSTI]

    Laura Bernard; Luc Blanchet; Lavinia Heisenberg

    2015-07-10

    We review some recent proposals for relativistic models of dark matter in the context of bimetric gravity. The aim is to solve the problems of cold dark matter (CDM) at galactic scales, and to reproduce the phenomenology of the modified Newtonian dynamics (MOND), while still being in agreement with the standard cosmological model $\\Lambda$-CDM at large scales. In this context a promising alternative is dipolar dark matter (DDM) in which two different species of dark matter particles are separately coupled to the two metrics of bigravity and are linked together by an internal vector field. The phenomenology of MOND then results from a mechanism of gravitational polarization. Probably the best formulation of the model is within the framework of recently developed massive bigravity theories. Then the gravitational sector of the model is safe by construction, but a ghostly degree of freedom in the decoupling limit is still present in the dark matter sector. Future work should analyse the cosmological solutions of the model and check the post-Newtonian parameters in the solar system.

  6. Anomalous transport and observable average in the standard map

    E-Print Network [OSTI]

    Lydia Bouchara; Ouerdia Ourrad; Sandro Vaienti; Xavier Leoncini

    2015-09-02

    The distribution of finite time observable averages and transport in low dimensional Hamiltonian systems is studied. Finite time observable average distributions are computed, from which an exponent $\\alpha$ characteristic of how the maximum of the distributions scales with time is extracted. To link this exponent to transport properties, the characteristic exponent $\\mu(q)$ of the time evolution of the different moments of order $q$ related to transport are computed. As a testbed for our study the standard map is used. The stochasticity parameter $K$ is chosen so that either phase space is mixed with a chaotic sea and islands of stability or with only a chaotic sea. Our observations lead to a proposition of a law relating the slope in $q=0$ of the function $\\mu(q)$ with the exponent $\\alpha$.

  7. A New World Average Value for the Neutron Lifetime

    E-Print Network [OSTI]

    A. P. Serebrov; A. K. Fomin

    2010-05-27

    The analysis of the data on measurements of the neutron lifetime is presented. A new most accurate result of the measurement of neutron lifetime [Phys. Lett. B 605 (2005) 72] 878.5 +/- 0.8 s differs from the world average value [Phys. Lett. B 667 (2008) 1] 885.7 +/- 0.8 s by 6.5 standard deviations. In this connection the analysis and Monte Carlo simulation of experiments [Phys. Lett. B 483 (2000) 15] and [Phys. Rev. Lett. 63 (1989) 593] is carried out. Systematic errors of about -6 s are found in each of the experiments. The summary table for the neutron lifetime measurements after corrections and additions is given. A new world average value for the neutron lifetime 879.9 +/- 0.9 s is presented.

  8. Modeling an Application's Theoretical Minimum and Average Transactional Response Times

    SciTech Connect (OSTI)

    Paiz, Mary Rose

    2015-04-01

    The theoretical minimum transactional response time of an application serves as a ba- sis for the expected response time. The lower threshold for the minimum response time represents the minimum amount of time that the application should take to complete a transaction. Knowing the lower threshold is beneficial in detecting anomalies that are re- sults of unsuccessful transactions. On the converse, when an application's response time falls above an upper threshold, there is likely an anomaly in the application that is causing unusual performance issues in the transaction. This report explains how the non-stationary Generalized Extreme Value distribution is used to estimate the lower threshold of an ap- plication's daily minimum transactional response time. It also explains how the seasonal Autoregressive Integrated Moving Average time series model is used to estimate the upper threshold for an application's average transactional response time.

  9. Average Interpolating Wavelets on Point Clouds and Graphs

    E-Print Network [OSTI]

    Rustamov, Raif M

    2011-01-01

    We introduce a new wavelet transform suitable for analyzing functions on point clouds and graphs. Our construction is based on a generalization of the average interpolating refinement scheme of Donoho. The most important ingredient of the original scheme that needs to be altered is the choice of the interpolant. Here, we define the interpolant as the minimizer of a smoothness functional, namely a generalization of the Laplacian energy, subject to the averaging constraints. In the continuous setting, we derive a formula for the optimal solution in terms of the poly-harmonic Green's function. The form of this solution is used to motivate our construction in the setting of graphs and point clouds. We highlight the empirical convergence of our refinement scheme and the potential applications of the resulting wavelet transform through experiments on a number of data stets.

  10. Average dynamics of a finite set of coupled phase oscillators

    SciTech Connect (OSTI)

    Dima, Germán C. Mindlin, Gabriel B.

    2014-06-15

    We study the solutions of a dynamical system describing the average activity of an infinitely large set of driven coupled excitable units. We compared their topological organization with that reconstructed from the numerical integration of finite sets. In this way, we present a strategy to establish the pertinence of approximating the dynamics of finite sets of coupled nonlinear units by the dynamics of its infinitely large surrogate.

  11. Averaging cross section data so we can fit it

    SciTech Connect (OSTI)

    Brown, D.

    2014-10-23

    The 56Fe cross section we are interested in have a lot of fluctuations. We would like to fit the average of the cross section with cross sections calculated within EMPIRE. EMPIRE is a Hauser-Feshbach theory based nuclear reaction code, requires cross sections to be smoothed using a Lorentzian profile. The plan is to fit EMPIRE to these cross sections in the fast region (say above 500 keV).

  12. Averaged equilibrium and stability in low-aspect-ratio stellarators

    SciTech Connect (OSTI)

    Garcia, L.; Carreras, B.A.; Dominguez, N.

    1989-01-01

    The MHD equilibrium and stability calculations or stellarators are complex because of the intrinsic three-dimensional (3-D) character of these configurations. The stellarators expansion simplifies the equilibrium calculation by reducing it to a two-dimensional (2-D) problem. The classical stellarator expansion includes terms up to order epsilon/sup 2/, and the vacuum magnetic field is also included up to this order. For large-aspect-ratio configurations, the results of the stellarator expansion agree well with 3-D numerical equilibrium results. But for low-aspect-ratio configurations, these are significant discrepancies with 3-D equilibrium calculations. The main reason for these discrepancies is the approximation in the vacuum field contributions. This problem can be avoided by applying the average method in a vacuum flux coordinate system. In this way, the exact vacuum magnetic field contribution is included and the results agree well with 3-D equilibrium calculations even for low-aspect-ratio configurations. Using the average method in a vacuum flux coordinate system also permit the accurate calculation of local stability properties with the Mercier criterion. The main improvement is in the accurate calculation of the geodesic curvature term. In this paper, we discuss the application of the average method in flux coordinates to the calculation of the Mercier criterion for low-aspect-ratio stellarator configurations. 12 refs., 3 figs.

  13. A Kinetic Theory Approach to Quantum Gravity

    E-Print Network [OSTI]

    B. L. Hu

    2002-04-22

    We describe a kinetic theory approach to quantum gravity -- by which we mean a theory of the microscopic structure of spacetime, not a theory obtained by quantizing general relativity. A figurative conception of this program is like building a ladder with two knotted poles: quantum matter field on the right and spacetime on the left. Each rung connecting the corresponding knots represent a distinct level of structure. The lowest rung is hydrodynamics and general relativity; the next rung is semiclassical gravity, with the expectation value of quantum fields acting as source in the semiclassical Einstein equation. We recall how ideas from the statistical mechanics of interacting quantum fields helped us identify the existence of noise in the matter field and its effect on metric fluctuations, leading to the establishment of the third rung: stochastic gravity, described by the Einstein-Langevin equation. Our pathway from stochastic to quantum gravity is via the correlation hierarchy of noise and induced metric fluctuations. Three essential tasks beckon: 1) Deduce the correlations of metric fluctuations from correlation noise in the matter field; 2) Reconstituting quantum coherence -- this is the reverse of decoherence -- from these correlation functions 3) Use the Boltzmann-Langevin equations to identify distinct collective variables depicting recognizable metastable structures in the kinetic and hydrodynamic regimes of quantum matter fields and how they demand of their corresponding spacetime counterparts. This will give us a hierarchy of generalized stochastic equations -- call them the Boltzmann-Einstein hierarchy of quantum gravity -- for each level of spacetime structure, from the macroscopic (general relativity) through the mesoscopic (stochastic gravity) to the microscopic (quantum gravity).

  14. Review on the quantization of gravity

    E-Print Network [OSTI]

    Benjamin Schulz

    2014-09-29

    This is a review article on quantum gravity. In section 1, the Penrose singularity theorem is proven. In section 2, the covariant quantization approach of gravity is reviewed. In section 3, an article by Hawking is reviewed that shows the gravitational path integral at one loop level to be dominated by contributions from some kind of virtual gravitational instantons. In section 4, the canonical, non-perturbative quantization approach is reviewed. In section 5, arguments from Hawking are mentioned which show the gravitational path integral to be an approximate solution of the Wheeler deWitt equation. In section 6, the black hole entropy is derived in various ways. Section 6.1 uses the gravitational path integral for this calculation. Section 6.2 shows how the black hole entropy can be derived from canonical quantum gravity. In section 7.1, arguments from Dvali and Gomez who claim that gravity can be quantized in a way which would be in some sense self-complete are critically assessed. In section 7.2 a model from Dvali and Gomez for the description of quantum mechanical black holes is critically assessed and compared with the standard quantization methods of gravity.

  15. Neutron stars: compact objects with relativistic gravity

    E-Print Network [OSTI]

    Ek?i, K Yavuz

    2015-01-01

    General properties of neutron stars are briefly reviewed with an emphasis on the indispensability of general relativity in our understanding of these fascinating objects. In Newtonian gravity the pressure within a star merely plays the role of opposing self-gravity. In general relativity all sources of energy and momentum contribute to the gravity. As a result the pressure not only opposes gravity but also enhances it. The later role of pressure becomes more pronounced with increasing compactness, $M/R$ where $M$ and $R$ are the mass and radius of the star, and sets a critical mass beyond which collapse is inevitable. This critical mass has no Newtonian analogue; it is conceptually different than the Stoner-Landau-Chandrasekhar limit in Newtonian gravity which is attained asymptotically for ultra-relativistic fermions. For white dwarfs the general relativistic critical mass is very close to the Stoner-Landau-Chandrasekhar limit. For neutron stars the maximum mass---so called Oppenheimer-Volkoff limit---is sig...

  16. Massive gravity wrapped in the cosmic web

    SciTech Connect (OSTI)

    Shim, Junsup; Lee, Jounghun; Li, Baojiu E-mail: jounghun@astro.snu.ac.kr

    2014-03-20

    We study how the filamentary pattern of the cosmic web changes if the true gravity deviates from general relativity (GR) on a large scale. The f(R) gravity, whose strength is controlled to satisfy the current observational constraints on the cluster scale, is adopted as our fiducial model and a large, high-resolution N-body simulation is utilized for this study. By applying the minimal spanning tree algorithm to the halo catalogs from the simulation at various epochs, we identify the main stems of the rich superclusters located in the most prominent filamentary section of the cosmic web and determine their spatial extents per member cluster to be the degree of their straightness. It is found that the f(R) gravity has the effect of significantly bending the superclusters and that the effect becomes stronger as the universe evolves. Even in the case where the deviation from GR is too small to be detectable by any other observables, the degree of the supercluster straightness exhibits a conspicuous difference between the f(R) and the GR models. Our results also imply that the supercluster straightness could be a useful discriminator of f(R) gravity from the coupled dark energy since it is shown to evolve differently between the two models. As a final conclusion, the degree of the straightness of the rich superclusters should provide a powerful cosmological test of large scale gravity.

  17. Einstein–Cartan gravity, Asymptotic Safety, and the running Immirzi parameter

    SciTech Connect (OSTI)

    Daum, J.-E.; Reuter, M.

    2013-07-15

    In this paper we analyze the functional renormalization group flow of quantum gravity on the Einstein–Cartan theory space. The latter consists of all action functionals depending on the spin connection and the vielbein field (co-frame) which are invariant under both spacetime diffeomorphisms and local frame rotations. In the first part of the paper we develop a general methodology and corresponding calculational tools which can be used to analyze the flow equation for the pertinent effective average action for any truncation of this theory space. In the second part we apply it to a specific three-dimensional truncated theory space which is parametrized by Newton’s constant, the cosmological constant, and the Immirzi parameter. A comprehensive analysis of their scale dependences is performed, and the possibility of defining an asymptotically safe theory on this hitherto unexplored theory space is investigated. In principle Asymptotic Safety of metric gravity (at least at the level of the effective average action) is neither necessary nor sufficient for Asymptotic Safety on the Einstein–Cartan theory space which might accommodate different “universality classes” of microscopic quantum gravity theories. Nevertheless, we do find evidence for the existence of at least one non-Gaussian renormalization group fixed point which seems suitable for the Asymptotic Safety construction in a setting where the spin connection and the vielbein are the fundamental field variables. -- Highlights: •A functional RG equation for a first order formulation of gravity is constructed. •The theory space constituted by tetrad and spin connection variables is explored. •The RG equation is solved in a 3 dimensional truncation of theory space. •The flow of Newton’s constant, the cosmological constant and the Immirzi parameter is analyzed. •Evidence for the nonperturbative renormalizability of the theory is found.

  18. Astrophysical black holes in screened modified gravity

    SciTech Connect (OSTI)

    Davis, Anne-Christine; Jha, Rahul; Muir, Jessica; Gregory, Ruth E-mail: r.a.w.gregory@durham.ac.uk E-mail: jlmuir@umich.edu

    2014-08-01

    Chameleon, environmentally dependent dilaton, and symmetron gravity are three models of modified gravity in which the effects of the additional scalar degree of freedom are screened in dense environments. They have been extensively studied in laboratory, cosmological, and astrophysical contexts. In this paper, we present a preliminary investigation into whether additional constraints can be provided by studying these scalar fields around black holes. By looking at the properties of a static, spherically symmetric black hole, we find that the presence of a non-uniform matter distribution induces a non-constant scalar profile in chameleon and dilaton, but not necessarily symmetron gravity. An order of magnitude estimate shows that the effects of these profiles on in-falling test particles will be sub-leading compared to gravitational waves and hence observationally challenging to detect.

  19. Charged black holes in generalized teleparallel gravity

    SciTech Connect (OSTI)

    Rodrigues, M.E.; Houndjo, M.J.S.; Tossa, J.; Momeni, D.; Myrzakulov, R. E-mail: sthoundjo@yahoo.fr E-mail: d.momeni@yahoo.com

    2013-11-01

    In this paper we investigate charged static black holes in 4D for generalized teleparallel models of gravity, based on torsion as the geometric object for describing gravity according to the equivalence principle. As a motivated idea, we introduce a set of non-diagonal tetrads and derive the full system of non linear differential equations. We prove that the common Schwarzschild gauge is applicable only when we study linear f(T) case. We reobtain the Reissner-Nordstrom-de Sitter (or RN-AdS) solution for the linear case of f(T) and perform a parametric cosmological reconstruction for two nonlinear models. We also study in detail a type of the no-go theorem in the framework of this modified teleparallel gravity.

  20. Fermion Doubling in Loop Quantum Gravity

    E-Print Network [OSTI]

    Jacob Barnett; Lee Smolin

    2015-07-05

    In this paper, we show that the Hamiltonian approach to loop quantum gravity has a fermion doubling problem. To obtain this result, we couple loop quantum gravity to a free massless scalar and a chiral fermion field, gauge fixing the many fingered time gauge invariance by interpreting the scalar field as a physical clock. We expand around a quantum gravity state based on a regular lattice and consider the limit where the bare cosmological constant is large but the fermonic excitations have energies low in Planck units. We then make the case for identifying the energy spectrum in this approximation with that of a model of lattice fermion theory which is known to double.

  1. Quantum gravity effects in the Kerr spacetime

    SciTech Connect (OSTI)

    Reuter, M.; Tuiran, E.

    2011-02-15

    We analyze the impact of the leading quantum gravity effects on the properties of black holes with nonzero angular momentum by performing a suitable renormalization group improvement of the classical Kerr metric within quantum Einstein gravity. In particular, we explore the structure of the horizons, the ergosphere, and the static limit surfaces as well as the phase space available for the Penrose process. The positivity properties of the effective vacuum energy-momentum tensor are also discussed and the 'dressing' of the black hole's mass and angular momentum are investigated by computing the corresponding Komar integrals. The pertinent Smarr formula turns out to retain its classical form. As for their thermodynamical properties, a modified first law of black-hole thermodynamics is found to be satisfied by the improved black holes (to second order in the angular momentum); the corresponding Bekenstein-Hawking temperature is not proportional to the surface gravity.

  2. Solar System Constraints on Disformal Gravity Theories

    E-Print Network [OSTI]

    Hiu Yan Ip; Jeremy Sakstein; Fabian Schmidt

    2015-10-15

    Disformal theories of gravity are scalar-tensor theories where the scalar couples derivatively to matter via the Jordan frame metric. These models have recently attracted interest in the cosmological context since they admit accelerating solutions. We derive the solution for a static isolated mass in generic disformal gravity theories and transform it into the parameterised post-Newtonian form. This allows us to investigate constraints placed on such theories by local tests of gravity. The tightest constraints come from preferred-frame effects due to the motion of the Solar System with respect to the evolving cosmological background field. The constraints we obtain improve upon the previous solar system constraints by two orders of magnitude, and constrain the scale of the disformal coupling for generic models to $\\mathcal{M} \\gtrsim 100$ eV. These constraints render all disformal effects irrelevant for cosmology.

  3. Detailed balance in Horava-Lifshitz gravity

    E-Print Network [OSTI]

    Gianluca Calcagni

    2010-02-04

    We study Horava-Lifshitz gravity in the presence of a scalar field. When the detailed balance condition is implemented, a new term in the gravitational sector is added in order to maintain ultraviolet stability. The four-dimensional theory is of a scalar-tensor type with a positive cosmological constant and gravity is nonminimally coupled with the scalar and its gradient terms. The scalar field has a double-well potential and, if required to play the role of the inflation, can produce a scale-invariant spectrum. The total action is rather complicated and there is no analog of the Einstein frame where Lorentz invariance is recovered in the infrared. For these reasons it may be necessary to abandon detailed balance. We comment on open problems and future directions in anisotropic critical models of gravity.

  4. Solar System Constraints on Disformal Gravity Theories

    E-Print Network [OSTI]

    Ip, Hiu Yan; Schmidt, Fabian

    2015-01-01

    Disformal theories of gravity are scalar-tensor theories where the scalar couples derivatively to matter via the Jordan frame metric. These models have recently attracted interest in the cosmological context since they admit accelerating solutions. We derive the solution for a static isolated mass in generic disformal gravity theories and transform it into the parameterised post-Newtonian form. This allows us to investigate constraints placed on such theories by local tests of gravity. The tightest constraints come from preferred-frame effects due to the motion of the Solar System with respect to the evolving cosmological background field. The constraints we obtain improve upon the previous solar system constraints by two orders of magnitude, and constrain the scale of the disformal coupling for generic models to $\\mathcal{M} \\gtrsim 100$ eV. These constraints render all disformal effects irrelevant for cosmology.

  5. Gravity tests and the Pioneer anomaly

    E-Print Network [OSTI]

    Marc-Thierry Jaekel; Serge Reynaud

    2005-11-04

    Experimental tests of gravity performed in the solar system show a good agreement with general relativity. The latter is however challenged by the Pioneer anomaly which might be pointing at some modification of gravity law at ranges of the order of the size of the solar system. We introduce a metric extension of general relativity which, while preserving the equivalence principle, modifies the coupling between curvature and stress tensors and, therefore, the metric solution in the solar system. The ``post-Einsteinian extension'' replaces Newton gravitation constant by two running coupling constants, which depend on the scale and differ in the sectors of traceless and traced tensors, so that the metric solution is characterized by two gravitation potentials. The extended theory has the capability to preserve compatibility with gravity tests while accounting for the Pioneer anomaly. It can also be tested by new experiments or, maybe, by having a new look at data of already performed experiments.

  6. Solar System Constraints on Disformal Gravity Theories

    E-Print Network [OSTI]

    Hiu Yan Ip; Jeremy Sakstein; Fabian Schmidt

    2015-07-02

    Disformal theories of gravity are scalar-tensor theories where the scalar couples derivatively to matter via the Jordan frame metric. These models have recently attracted interest in the cosmological context since they admit accelerating solutions. We derive the solution for a static isolated mass in generic disformal gravity theories and transform it into the parameterised post-Newtonian form. This allows us to investigate constraints placed on such theories by local tests of gravity. The tightest constraints come from preferred-frame effects due to the motion of the Solar System with respect to the evolving cosmological background field. The constraints we obtain improve upon the previous solar system constraints by two orders of magnitude, and constrain the scale of the disformal coupling for generic models to $\\mathcal{M} \\gtrsim 100$ eV. These constraints render all disformal effects irrelevant for cosmology.

  7. (Approximate) Low-Mode Averaging with a new Multigrid Eigensolver

    E-Print Network [OSTI]

    Gunnar Bali; Sara Collins; Andreas Frommer; Karsten Kahl; Issaku Kanamori; Benjamin Müller; Matthias Rottmann; Jakob Simeth

    2015-09-23

    We present a multigrid based eigensolver for computing low-modes of the Hermitian Wilson Dirac operator. For the non-Hermitian case multigrid methods have already replaced conventional Krylov subspace solvers in many lattice QCD computations. Since the $\\gamma_5$-preserving aggregation based interpolation used in our multigrid method is valid for both, the Hermitian and the non-Hermitian case, inversions of very ill-conditioned shifted systems with the Hermitian operator become feasible. This enables the use of multigrid within shift-and-invert type eigensolvers. We show numerical results from our MPI-C implementation of a Rayleigh quotient iteration with multigrid. For state-of-the-art lattice sizes and moderate numbers of desired low-modes we achieve speed-ups of an order of magnitude and more over PARPACK. We show results and develop strategies how to make use of our eigensolver for calculating disconnected contributions to hadronic quantities that are noisy and still computationally challenging. Here, we explore the possible benefits, using our eigensolver for low-mode averaging and related methods with high and low accuracy eigenvectors. We develop a low-mode averaging type method using only a few of the smallest eigenvectors with low accuracy. This allows us to avoid expensive exact eigensolves, still benefitting from reduced statistical errors.

  8. Averaged null energy condition and quantum inequalities in curved spacetime

    E-Print Network [OSTI]

    Eleni-Alexandra Kontou

    2015-07-22

    The Averaged Null Energy Condition (ANEC) states that the integral along a complete null geodesic of the projection of the stress-energy tensor onto the tangent vector to the geodesic cannot be negative. ANEC can be used to rule out spacetimes with exotic phenomena, such as closed timelike curves, superluminal travel and wormholes. We prove that ANEC is obeyed by a minimally-coupled, free quantum scalar field on any achronal null geodesic (not two points can be connected with a timelike curve) surrounded by a tubular neighborhood whose curvature is produced by a classical source. To prove ANEC we use a null-projected quantum inequality, which provides constraints on how negative the weighted average of the renormalized stress-energy tensor of a quantum field can be. Starting with a general result of Fewster and Smith, we first derive a timelike projected quantum inequality for a minimally-coupled scalar field on flat spacetime with a background potential. Using that result we proceed to find the bound of a quantum inequality on a geodesic in a spacetime with small curvature, working to first order in the Ricci tensor and its derivatives. The last step is to derive a bound for the null-projected quantum inequality on a general timelike path. Finally we use that result to prove achronal ANEC in spacetimes with small curvature.

  9. Averaged null energy condition and quantum inequalities in curved spacetime

    E-Print Network [OSTI]

    Kontou, Eleni-Alexandra

    2015-01-01

    The Averaged Null Energy Condition (ANEC) states that the integral along a complete null geodesic of the projection of the stress-energy tensor onto the tangent vector to the geodesic cannot be negative. ANEC can be used to rule out spacetimes with exotic phenomena, such as closed timelike curves, superluminal travel and wormholes. We prove that ANEC is obeyed by a minimally-coupled, free quantum scalar field on any achronal null geodesic (not two points can be connected with a timelike curve) surrounded by a tubular neighborhood whose curvature is produced by a classical source. To prove ANEC we use a null-projected quantum inequality, which provides constraints on how negative the weighted average of the renormalized stress-energy tensor of a quantum field can be. Starting with a general result of Fewster and Smith, we first derive a timelike projected quantum inequality for a minimally-coupled scalar field on flat spacetime with a background potential. Using that result we proceed to find the bound of a qu...

  10. Plasma dynamics and a significant error of macroscopic averaging

    E-Print Network [OSTI]

    Marek A. Szalek

    2005-05-22

    The methods of macroscopic averaging used to derive the macroscopic Maxwell equations from electron theory are methodologically incorrect and lead in some cases to a substantial error. For instance, these methods do not take into account the existence of a macroscopic electromagnetic field EB, HB generated by carriers of electric charge moving in a thin layer adjacent to the boundary of the physical region containing these carriers. If this boundary is impenetrable for charged particles, then in its immediate vicinity all carriers are accelerated towards the inside of the region. The existence of the privileged direction of acceleration results in the generation of the macroscopic field EB, HB. The contributions to this field from individual accelerated particles are described with a sufficient accuracy by the Lienard-Wiechert formulas. In some cases the intensity of the field EB, HB is significant not only for deuteron plasma prepared for a controlled thermonuclear fusion reaction but also for electron plasma in conductors at room temperatures. The corrected procedures of macroscopic averaging will induce some changes in the present form of plasma dynamics equations. The modified equations will help to design improved systems of plasma confinement.

  11. The inverse-square law and quantum gravity

    SciTech Connect (OSTI)

    Nieto, M.M.; Goldman, T.; Hughes, R.J.

    1988-01-01

    This paper briefly discusses a modification to central potential of gravity when antimatter is involved and the possible existence of quantum gravity and a fifth force of nature. 1 ref. (LSP)

  12. Correlation Between Precision Gravity and Subsidence Measurements at Cerro Prieto

    E-Print Network [OSTI]

    Zelwer, R.

    2010-01-01

    PRECISION GRAVITY AND SUBSIDENCE MEASUREMENTS AT CERROPRECISION GRAVITY AND SUBSIDENCE MEASUREMENTS AT CERROn d i c a t e s t h a t subsidence took place. Uost of t h e

  13. Theoretical and experimental study of nonlinear internal gravity wave beams

    E-Print Network [OSTI]

    Tabaei Befrouei, Ali, 1974-

    2005-01-01

    Continuously stratified fluids, like the atmosphere and the oceans, support internal gravity waves due to the effect of buoyancy. This type of wave motion is anisotropic since gravity provides a preferred direction. As a ...

  14. Stratospheric gravity wave simulation over Greenland during 24 January 2005

    E-Print Network [OSTI]

    Limpasuvan, Varavut

    gravity waves because of imbalance of the jet stream. Where the horizontal jet is rapidly changing speed anticyclonic jet stream over the North Atlantic. Likewise, inertia gravity waves can result from synoptic

  15. Gravity modeling of Cenozoic extensional basins, offshore Vietnam 

    E-Print Network [OSTI]

    Mauri, Steven Joseph

    1993-01-01

    Integrating Bouguer gravity and satellite-derived free-air gravity data with published geological and geophysical data allows modeling crustal structure and estimating crustal extension for the hydrocarbon bearing Mekong and Song Hong - Yinggehai...

  16. Ground Gravity Survey At Baltazor Hot Springs Area (Isherwood...

    Open Energy Info (EERE)

    (Fig. 2) shows a gravity low within the valley area that presumably is related to low-density Cenozoic sediments. The steep gravity gradient along the east side of the valley...

  17. A Finite Quantum Gravity Field Theory Model

    E-Print Network [OSTI]

    Jorge Alfaro; Pablo González; Ricardo Avila

    2011-09-22

    We discuss the quantization of Delta gravity, a two symmetric tensors model of gravity. This model, in Cosmology, shows accelerated expansion without a cosmological constant. We present the $\\tilde{\\delta}$ transformation which defines the geometry of the model. Then we show that all delta type models live at one loop only. We apply this to General Relativity and we calculate the one loop divergent part of the Effective Action showing its null contribution in vacuum, implying a finite model. Then we proceed to study the existence of ghosts in the model. Finally, we study the form of the finite quantum corrections to the classical action of the model.

  18. Differential geometry, Palatini gravity and reduction

    SciTech Connect (OSTI)

    Capriotti, S.

    2014-01-15

    The present article deals with a formulation of the so called (vacuum) Palatini gravity as a general variational principle. In order to accomplish this goal, some geometrical tools related to the geometry of the bundle of connections of the frame bundle LM are used. A generalization of Lagrange-Poincaré reduction scheme to these types of variational problems allows us to relate it with the Einstein-Hilbert variational problem. Relations with some other variational problems for gravity found in the literature are discussed.

  19. Cosmological Evidence for Modified Gravity (MOG)

    E-Print Network [OSTI]

    Moffat, J W

    2015-01-01

    Deviations from the standard $\\Lambda$CDM model motivate an interpretation of early universe cosmology using the Scalar-Tensor-Vector-Gravity (STVG) theory. A constraint analysis carried out by Valentino, Melchiorri and Silk, revealed deviations from the growth of structure predicted by General Relativity, and a lensing anomaly in the angular CMB power spectrum data with a $95\\%$ c.l. The modified gravity (MOG) theory resolves the lensing deviation from the standard model and provides an explanation of the CMB and structure growth data.

  20. Violation of Energy Bounds in Designer Gravity

    E-Print Network [OSTI]

    Thomas Hertog

    2006-07-31

    We continue our study of the stability of designer gravity theories, where one considers anti-de Sitter gravity coupled to certain tachyonic scalars with boundary conditions defined by a smooth function W. It has recently been argued there is a lower bound on the conserved energy in terms of the global minimum of W, if the scalar potential arises from a superpotential P and the scalar reaches an extremum of P at infinity. We show, however, there are superpotentials for which these bounds do not hold.

  1. Prima Facie Questions in Quantum Gravity

    E-Print Network [OSTI]

    C. J. Isham

    1993-10-22

    The long history of the study of quantum gravity has thrown up a complex web of ideas and approaches. The aim of this article is to unravel this web a little by analysing some of the {\\em prima facie\\/} questions that can be asked of almost any approach to quantum gravity and whose answers assist in classifying the different schemes. Particular emphasis is placed on (i) the role of background conceptual and technical structure; (ii) the role of spacetime diffeomorphisms; and (iii) the problem of time.

  2. Linear Stability Analysis of Dynamical Quadratic Gravity

    E-Print Network [OSTI]

    Dimitry Ayzenberg; Kent Yagi; Nicolas Yunes

    2014-03-18

    We perform a linear stability analysis of dynamical, quadratic gravity in the high-frequency, geometric optics approximation. This analysis is based on a study of gravitational and scalar modes propagating on spherically-symmetric and axially-symmetric, vacuum solutions of the theory. We find dispersion relations that do no lead to exponential growth of the propagating modes, suggesting the theory is linearly stable on these backgrounds. The modes are found to propagate at subluminal and superluminal speeds, depending on the propagating modes' direction relative to the background geometry, just as in dynamical Chern-Simons gravity.

  3. Nonlocal Gravity in the Solar System

    E-Print Network [OSTI]

    Chicone, C

    2015-01-01

    The implications of the recent classical nonlocal generalization of Einstein's theory of gravitation for gravitational physics in the Solar System are investigated. In this theory, the nonlocal character of gravity simulates dark matter. Nonlocal gravity in the Newtonian regime involves a reciprocal kernel with three spatial parameters, of which two have already been determined from the rotation curves of spiral galaxies and the internal dynamics of clusters of galaxies. However, the short-range parameter a_0 remains to be determined. In this connection, the nonlocal contribution to the perihelion precession of a planetary orbit is estimated and a preliminary lower limit on a_0 is determined.

  4. Spacetime, Spin and Gravity Probe B

    E-Print Network [OSTI]

    James M. Overduin

    2015-04-22

    It is more important than ever to push experimental tests of gravitational theory to the limits of existing technology in both range and sensitivity. This brief review focuses on spin-based tests of General Relativity and their implications for alternative, mostly non-metric theories of gravity motivated by the challenge of unification with the Standard Model of particle physics. The successful detection of geodetic precession and frame-dragging by Gravity Probe B places new constraints on a number of these theories, and increases our confidence in the theoretical mechanisms underpinning current ideas in astrophysics and cosmology.

  5. Energy Distribution in f(R) Gravity

    E-Print Network [OSTI]

    M. Sharif; M. Farasat Shamir

    2009-12-18

    The well-known energy problem is discussed in f(R) theory of gravity. We use the generalized Landau-Lifshitz energy-momentum complex in the framework of metric f(R) gravity to evaluate the energy density of plane symmetric solutions for some general f(R) models. In particular, this quantity is found for some popular choices of f(R) models. The constant scalar curvature condition and the stability condition for these models are also discussed. Further, we investigate the energy distribution of cosmic string spacetime.

  6. Holographic superconductors from the massive gravity

    E-Print Network [OSTI]

    Hua Bi Zeng; Jian-Pin Wu

    2014-09-24

    A holographic superconductor is constructed in the background of a massive gravity theory. In the normal state without condensation, the conductivity exhibits a Drude peak that approaches a delta function in the massless gravity limit as studied by David Vegh. In the superconducting state, besides the infinite DC conductivity, the AC conductivity has Drude behavior at low frequency followed by a power law-fall. These results are in agreement with that found earlier by Horowitz and Santos, who studied a holographic superconductor with an implicit periodic potential beyond the probe limit. The results also agree with measurements on some cuprates.

  7. Gravity currents filling basins: the influence of Reynolds number on entrainment into gravity currents

    E-Print Network [OSTI]

    Hogg, Charlie A. R.; Dalziel, Stuart B.; Huppert, Herbert E.; Imberger, Jörg

    2015-01-01

    by noise in the conductivity measurements which was minimised by the median 10 Gravity currents filling basins: influence of Reynolds number on entrainment Source x z Outflow ? D zf A = D/(sin ? cos ?) FIG. 6: Schematic of the basin. The gravity current... in these experiments, the horizontal length at the top of the basin is A = D/(sin ? cos ?) . The virtual origin is the origin for a source of buoyancy alone that would give rise to the volume and buoyancy flux that occurs at the physical origin. 12 Gravity currents...

  8. Violation of the Holographic Principle in the Loop Quantum Gravity

    E-Print Network [OSTI]

    Ozan Sarg?n; Mir Faizal

    2015-09-01

    In this paper, we analyze the holographic principle using loop quantum gravity (LQG). This will be done by analysing a simple quantum mechanical system using polymeric quantization. As the polymeric quantization is the characteristic feature of loop quantum gravity, we will argue that this calculation will indicate the effect on the holographic principle from the loop quantum gravity. Thus, we will be able to explicitly demonstrate the violation of the holographic principle in the loop quantum gravity.

  9. Quantum reduced loop gravity: extension to scalar field

    E-Print Network [OSTI]

    Jakub Bilski; Emanuele Alesci; Francesco Cianfrani

    2015-07-02

    The quantization of the Hamiltonian for a scalar field is performed in the framework of Quantum Reduced Loop Gravity. We outline how the regularization can be performed by using the analogous tools adopted in full Loop Quantum Gravity and the matrix elements of the resulting operator between basis states are analytic coefficients. These achievements open the way for a consistent analysis of the Quantum Gravity corrections to the classical dynamics of gravity in the presence of a scalar field in a cosmological setting.

  10. Gravity currents in two-layer stratified media

    E-Print Network [OSTI]

    Flynn, Morris R.

    Gravity currents in two-layer stratified media Morris R. Flynn & Alan W.Tan Dept. of Mechanical Engineering, U.Alberta Funding: NSERC #12;· Gravity currents appear over a broad range of time/length scales. (1999), Flynn & Linden (2006),White & Helfrich (2008), Ungarish (2009) Introduction current gravity

  11. Gravity Surface Wave Bifurcation in a Highly Turbulent Swirling Flow

    E-Print Network [OSTI]

    Witten, Thomas A.

    Gravity Surface Wave Bifurcation in a Highly Turbulent Swirling Flow Michael Baumer University Gravity Wave 2 3 Measurements 3 4 Mechanical Hardware: Problems and Solutions 5 5 Results 7 6 Conclusions investigated a free-surface gravity wave bifurcation in the large-separation regime, that is, where

  12. Gravity Wave Lensing Ryan Elandt, Mostafa Shakeri & Reza Alam

    E-Print Network [OSTI]

    Alam, Mohammad-Reza

    Gravity Wave Lensing Ryan Elandt, Mostafa Shakeri & Reza Alam Department of Mechanical Engineering waves caused by small seabed features (the so called Bragg resonance) can be utilized to create equivalent of lenses and curved mirrors for surface gravity waves. Such gravity wave lenses, which are merely

  13. Average vertical and zonal F region plasma drifts over Jicamarca

    SciTech Connect (OSTI)

    Fejer, B.G.; Gonzalez, S.A. (Utah State Univ., Logan (United States)); de Paula, E.R. (Inst. de Pesquisas Espaciais-INPE, Sao Paulo (Brazil) Utah State Univ., Logan (United States)); Woodman, R.F. (Inst. Geofisico del Peru, Lima (Peru))

    1991-08-01

    The seasonal averages of the equatorial F region vertical and zonal plasma drifts are determined using extensive incoherent scatter radar observations from Jicamarca during 1968-1988. The late afternoon and nighttime vertical and zonal drifts are strongly dependent on the 10.7-cm solar flux. The authors show that the evening prereversal enhancement of vertical drifts increases linearly with solar flux during equinox but tends to saturate for large fluxes during southern hemisphere winter. They examine in detail, for the first time, the seasonal variation of the zonal plasma drifts and their dependence on solar flux and magnetic activity. The seasonal effects on the zonal drifts are most pronounced in the midnight-morning sector. The nighttime eastward drifts increase with solar flux for all seasons but decrease slightly with magnetic activity. The daytime westward drifts are essentially independent of season, solar cycle, and magnetic activity.

  14. Average System Cost Methodology : Administrator's Record of Decision.

    SciTech Connect (OSTI)

    United States. Bonneville Power Administration.

    1984-06-01

    Significant features of average system cost (ASC) methodology adopted are: retention of the jurisdictional approach where retail rate orders of regulartory agencies provide primary data for computing the ASC for utilities participating in the residential exchange; inclusion of transmission costs; exclusion of construction work in progress; use of a utility's weighted cost of debt securities; exclusion of income taxes; simplification of separation procedures for subsidized generation and transmission accounts from other accounts; clarification of ASC methodology rules; more generous review timetable for individual filings; phase-in of reformed methodology; and each exchanging utility must file under the new methodology within 20 days of implementation by the Federal Energy Regulatory Commission of the ten major participating utilities, the revised ASC will substantially only affect three. (PSB)

  15. The Mars Gravity Biosatellite as an innovative partial gravity research platform

    E-Print Network [OSTI]

    Fulford-Jones, Thaddeus R. F

    2008-01-01

    The Mars Gravity Biosatellite is an unprecedented independent spaceflight platform for gravitational biology research. With a projected first launch after 2010, the low Earth orbit satellite will support a cohort of fifteen ...

  16. The diffeomorphism algebra approach to quantum gravity

    E-Print Network [OSTI]

    T. A. Larsson

    1999-09-13

    The representation theory of non-centrally extended Lie algebras of Noether symmetries, including spacetime diffeomorphisms and reparametrizations of the observer's trajectory, has recently been developped. It naturally solves some long-standing problems in quantum gravity, e.g. the role of diffeomorphisms and the causal structure, but some new questions also arise.

  17. Topological Black Holes in Quantum Gravity

    E-Print Network [OSTI]

    J. Kowalski-Glikman; D. Nowak-Szczepaniak

    2000-07-31

    We derive the black hole solutions with horizons of non-trivial topology and investigate their properties in the framework of an approach to quantum gravity being an extension of Bohm's formulation of quantum mechanics. The solutions we found tend asymptotically (for large $r$) to topological black holes. We also analyze the thermodynamics of these space-times.

  18. Energy definition for quadratic curvature gravities

    E-Print Network [OSTI]

    Ahmet Baykal

    2012-12-03

    A conserved current for generic quadratic curvature gravitational models is defined, and it is shown that, at the linearized level, it corresponds to the Deser-Tekin charges. An explicit expression for the charge for new massive gravity in three dimensions is given. Some implications of the linearized equations are discussed.

  19. p-wave superconductors in dilaton gravity

    E-Print Network [OSTI]

    ZhongYing Fan

    2013-10-08

    In this paper, we study peculiar properties of p-wave superconductors in dilaton gravity. The scale invariance of the bulk geometry is effectively broken due to the existence of dilaton. By coupling the dilaton to the non-Abelian gauge field, i.e., $-\\frac14 e^{-\\beta \\Phi} F^a_{\\mu\

  20. Ultrasonic hydrometer. [Specific gravity of electrolyte

    DOE Patents [OSTI]

    Swoboda, C.A.

    1982-03-09

    The disclosed ultrasonic hydrometer determines the specific gravity (density) of the electrolyte of a wet battery, such as a lead-acid battery. The hydrometer utilizes a transducer that when excited emits an ultrasonic impulse that traverses through the electrolyte back and forth between spaced sonic surfaces. The transducer detects the returning impulse, and means measures the time t between the initial and returning impulses. Considering the distance d between the spaced sonic surfaces and the measured time t, the sonic velocity V is calculated with the equation V = 2d/t. The hydrometer also utilizes a thermocouple to measure the electrolyte temperature. A hydrometer database correlates three variable parameters including sonic velocity in and temperature and specific gravity of the electrolyte, for temperature values between 0 and 40/sup 0/C and for specific gravity values between 1.05 and 1.30. Upon knowing two parameters (the calculated sonic velocity and the measured temperature), the third parameter (specific gravity) can be uniquely found in the database. The hydrometer utilizes a microprocessor for data storage and manipulation.

  1. Topology in 4D simplicial quantum gravity

    E-Print Network [OSTI]

    S. Bilke; Z. Burda; B. Petersson

    1996-11-22

    We simulate 4d simplicial gravity for three topologis S4, S3xS1, (S1)^4 and show that the free energy for these three fixed topology ensembles is the same in the thermodynamic limit. We show, that the next-to-leading order corrections, at least away from the critical point, can be described by kinematic sources.

  2. Modified Force-Directed Scheduling for Peak and Average Power Optimization using Multiple Supply-Voltages

    E-Print Network [OSTI]

    Ramanujam, J. "Ram"

    - and a is the average number of transitions per clock phase heuristic for peak and average power cycle at the gate

  3. On the z=4 Horava-Lifshitz Gravity

    E-Print Network [OSTI]

    Rong-Gen Cai; Yan Liu; Ya-Wen Sun

    2009-06-04

    We consider z=4 Horava-Lifshitz gravity in both 3+1 and 4+1 dimensions. We find black hole solutions in the IR region for a kind of z=4 Horava-Lifshitz gravity which is inherited from the new massive gravity in three dimensions and an analog of the new massive gravity in four dimensions through the quantum inheritance principle. We analyze thermodynamic properties for the black hole solutions for z=4 Horava-Lifshitz gravity. We also write out the Friedmann equation in 3+1 dimensions for cosmological solutions.

  4. Measuring the Earth's gravity field with cold atom interferometers

    E-Print Network [OSTI]

    Olivier Carraz; Christian Siemes; Luca Massotti; Roger Haagmans; Pierluigi Silvestrin

    2015-06-12

    The scope of the paper is to propose different concepts for future space gravity missions using Cold Atom Interferometers (CAI) for measuring the diagonal elements of the gravity gradient tensor, the spacecraft angular velocity and the spacecraft acceleration. The aim is to achieve better performance than previous space gravity missions due to a very low white noise spectral behaviour of the CAI instrument and a very high common mode rejection, with the ultimate goals of determining the fine structures of the gravity field with higher accuracy than GOCE and detecting time-variable signals in the gravity field.

  5. Geodesic Deviation Equation in $f(T)$ gravity

    E-Print Network [OSTI]

    F. Darabi; M. Mousavi; K. Atazadeh

    2015-04-14

    In this work, we show that it is possible to study the notion of geodesic deviation equation in $f(T)$ gravity, in spite of the fact that in teleparallel gravity there is no notion of geodesics, and the torsion is responsible for the appearance of gravitational interaction. In this regard, we obtain the GR equivalent equations for $f(T)$ gravity which are in the modified gravity form such as $f(R)$ gravity. Then, we obtain the GDE within the context of this modified gravity. In this way, the obtained geodesic deviation equation will correspond to the $f(T)$ gravity. Eventually, we extend the calculations to obtain the modification of Matting relation.

  6. A SEA FLOOR GRAVITY SURVEY OF THE SLEIPNER FIELD TO MONITOR CO2 MIGRATION

    SciTech Connect (OSTI)

    Mark Zumberge; Scott Nooner; Ola Eiken

    2004-11-29

    Since 1996, excess CO{sub 2} from the Sleipner natural gas field has been sequestered and injected underground into a porous saline aquifer 1000 m below the seafloor. In 2002, we carried out a high precision micro-gravity survey on the seafloor in order to monitor the injected CO{sub 2}. A repeatability of 5 {micro}Gal in the station averages was observed. This is considerably better than pre-survey expectations. These data will serve as the baseline for time-lapse gravity monitoring of the Sleipner CO{sub 2} injection site. A repeat survey has been scheduled for the summer of 2005. This report covers 3/18/04 to 9/19/04. During this time, we participated in several CO{sub 2} sequestration-related meetings and conferences. On March 29, 2004, we participated in the 2004 Carbon Sequestration Project Review Meeting for the Department of Energy in Pittsburgh, PA. During the week of May 2, 2004, we attended and presented at the Third Annual Conference on Carbon Capture and Sequestration in Alexandria, VA. Finally, during the week of August 8, 2004, we took part in the U.S.-Norway, CO{sub 2} Summer School in Santa Fe, NM. Additional modeling was also completed, examining the seismic velocity pushdown estimates from the gravity models and the expected deformation of the seafloor due to the injected CO{sub 2}.

  7. A SEA FLOOR GRAVITY SURVEY OF THE SLEIPNER FIELD TO MONITOR CO2 MIGRATION

    SciTech Connect (OSTI)

    Mark Zuberge; Scott Nooner; Glenn Sasagawa

    2003-11-17

    Since 1996, excess CO{sub 2} from the Sleipner natural gas field has been sequestered and injected underground into a porous saline aquifer 1000 m below the seafloor. In 2002, we carried out a high precision micro-gravity survey on the seafloor in order to monitor the injected CO{sub 2}. A repeatability of 5 {micro}Gal in the station averages was observed. This is considerably better than pre-survey expectations. These data will serve as the baseline for time-lapse gravity monitoring of the Sleipner CO{sub 2} injection site. A three-week trip to Statoil Research Centre in Trondheim, Norway, was made in the summer of 2003. This visit consisted of gathering data and collaborating with scientists working on the Sleipner project. The trip ended with a presentation of the seafloor gravity results to date at a SACS2 (Saline Aquifer CO{sub 2} Storage 2) meeting. This meeting provided the perfect opportunity to meet and gather information from the world's experts on the Sleipner project.

  8. A SEA FLOOR GRAVITY SURVEY OF THE SLEIPNER FIELD TO MONITOR CO2 MIGRATION

    SciTech Connect (OSTI)

    Mark Zumberge; Scott Nooner

    2005-07-11

    Since 1996, excess CO{sub 2} from the Sleipner natural gas field has been sequestered and injected underground into a porous saline aquifer 1000 m below the seafloor. In 2002, we carried out a high precision micro-gravity survey on the seafloor in order to monitor the injected CO{sub 2}. A repeatability of 5 {micro}Gal in the station averages was observed. This is considerably better than pre-survey expectations. These data will serve as the baseline for time-lapse gravity monitoring of the Sleipner CO{sub 2} injection site. A repeat survey has been scheduled for the summer of 2005. This report covers 9/19/04 to 3/18/05. During this time, gravity and pressure modeling were completed and work graduate student Scott Nooner began writing his Ph.D. dissertation, of which this work is a the major part. Improvements to the gravimeters are also underway that will hopefully increase the measurement precision.

  9. Dosimetry in Mammography: Average Glandular Dose Based on Homogeneous Phantom

    SciTech Connect (OSTI)

    Benevides, Luis A. [Naval Sea Systems Command,1333 Isaac Hull Avenue, Washington Navy Yard, DC 20376 (United States); Hintenlang, David E. [University of Florida, 202 Nuclear Sciences Center, P.O. Box 1183, Gainesville Florida 32611 (United States)

    2011-05-05

    The objective of this study was to demonstrate that a clinical dosimetry protocol that utilizes a dosimetric breast phantom series based on population anthropometric measurements can reliably predict the average glandular dose (AGD) imparted to the patient during a routine screening mammogram. AGD was calculated using entrance skin exposure and dose conversion factors based on fibroglandular content, compressed breast thickness, mammography unit parameters and modifying parameters for homogeneous phantom (phantom factor), compressed breast lateral dimensions (volume factor) and anatomical features (anatomical factor). The patient fibroglandular content was evaluated using a calibrated modified breast tissue equivalent homogeneous phantom series (BRTES-MOD) designed from anthropomorphic measurements of a screening mammography population and whose elemental composition was referenced to International Commission on Radiation Units and Measurements Report 44 and 46 tissues. The patient fibroglandular content, compressed breast thickness along with unit parameters and spectrum half-value layer were used to derive the currently used dose conversion factor (DgN). The study showed that the use of a homogeneous phantom, patient compressed breast lateral dimensions and patient anatomical features can affect AGD by as much as 12%, 3% and 1%, respectively. The protocol was found to be superior to existing methodologies. The clinical dosimetry protocol developed in this study can reliably predict the AGD imparted to an individual patient during a routine screening mammogram.

  10. Long-term average performance benefits of parabolic trough improvements

    SciTech Connect (OSTI)

    Gee, R.; Gaul, H.W.; Kearney, D.; Rabl, A.

    1980-03-01

    Improved parabolic trough concentrating collectors will result from better design, improved fabrication techniques, and the development and utilization of improved materials. The difficulty of achieving these improvements varies as does their potential for increasing parabolic trough performance. The purpose of this analysis is to quantify the relative merit of various technology advancements in improving the long-term average performance of parabolic trough concentrating collectors. The performance benefits of improvements are determined as a function of operating temperature for north-south, east-west, and polar mounted parabolic troughs. The results are presented graphically to allow a quick determination of the performance merits of particular improvements. Substantial annual energy gains are shown to be attainable. Of the improvements evaluated, the development of stable back-silvered glass reflective surfaces offers the largest performance gain for operating temperatures below 150/sup 0/C. Above 150/sup 0/C, the development of trough receivers that can maintain a vacuum is the most significant potential improvement. The reduction of concentrator slope errors also has a substantial performance benefit at high operating temperatures.

  11. Ensemble bayesian model averaging using markov chain Monte Carlo sampling

    SciTech Connect (OSTI)

    Vrugt, Jasper A; Diks, Cees G H; Clark, Martyn P

    2008-01-01

    Bayesian model averaging (BMA) has recently been proposed as a statistical method to calibrate forecast ensembles from numerical weather models. Successful implementation of BMA however, requires accurate estimates of the weights and variances of the individual competing models in the ensemble. In their seminal paper (Raftery etal. Mon Weather Rev 133: 1155-1174, 2(05)) has recommended the Expectation-Maximization (EM) algorithm for BMA model training, even though global convergence of this algorithm cannot be guaranteed. In this paper, we compare the performance of the EM algorithm and the recently developed Differential Evolution Adaptive Metropolis (DREAM) Markov Chain Monte Carlo (MCMC) algorithm for estimating the BMA weights and variances. Simulation experiments using 48-hour ensemble data of surface temperature and multi-model stream-flow forecasts show that both methods produce similar results, and that their performance is unaffected by the length of the training data set. However, MCMC simulation with DREAM is capable of efficiently handling a wide variety of BMA predictive distributions, and provides useful information about the uncertainty associated with the estimated BMA weights and variances.

  12. High average power magnetic modulator for copper lasers

    SciTech Connect (OSTI)

    Cook, E.G.; Ball, D.G.; Birx, D.L.; Branum, J.D.; Peluso, S.E.; Langford, M.D.; Speer, R.D.; Sullivan, J.R.; Woods, P.G.

    1991-06-14

    Magnetic compression circuits show the promise of long life for operation at high average powers and high repetition rates. When the Atomic Vapor Laser Isotope Separation (AVLIS) Program at Lawrence Livermore National Laboratory needed new modulators to drive their higher power copper lasers in the Laser Demonstration Facility (LDF), existing technology using thyratron switched capacitor inversion circuits did not meet the goal for long lifetimes at the required power levels. We have demonstrated that magnetic compression circuits can achieve this goal. Improving thyratron lifetime is achieved by increasing the thyratron conduction time, thereby reducing the effect of cathode depletion. This paper describes a three stage magnetic modulator designed to provide a 60 kV pulse to a copper laser at a 4. 5 kHz repetition rate. This modulator operates at 34 kW input power and has exhibited MTBF of {approx}1000 hours when using thyratrons and even longer MTBFs with a series of stack of SCRs for the main switch. Within this paper, the electrical and mechanical designs for the magnetic compression circuits are discussed as are the important performance parameters of lifetime and jitter. Ancillary circuits such as the charge circuit and reset circuit are shown. 8 refs., 5 figs., 1 tab.

  13. Spatiotemporal measurement of surfactant distribution on gravity-capillary waves

    E-Print Network [OSTI]

    Strickland, Stephen L; Daniels, Karen E

    2015-01-01

    Materials adsorbed to the surface of a fluid -- for instance, crude oil, biogenic slicks, or industrial/medical surfactants -- will move in response to surface waves. Due to the difficulty of non-invasive measurement of the spatial distribution of a molecular monolayer, little is known about the dynamics that couple the surface waves and the evolving density field. Here, we report measurements of the spatiotemporal dynamics of the density field of an insoluble surfactant driven by gravity-capillary waves in a shallow cylindrical container. Standing Faraday waves and traveling waves generated by the meniscus are superimposed to create a non-trivial surfactant density field. We measure both the height field of the surface using moir\\'e-imaging, and the density field of the surfactant via the fluorescence of NBD-tagged phosphatidylcholine, a lipid. Through phase-averaging stroboscopically-acquired images of the density field, we determine that the surfactant accumulates on the leading edge of the traveling menis...

  14. Effect of gravity on three-dimensional coordination number distribution in liquid phase sintered microstructures

    SciTech Connect (OSTI)

    Tewari, A.; Gokhale, A.M.; Gereman, R.M.

    1999-10-08

    Gravity affects microstructural evolution when a liquid phase is present during sintering. The effect of gravity on the three-dimensional coordination number distribution of tungsten grains in liquid phase sintered heavy alloy specimens is quantitatively characterized. A combination of montage serial sectioning, digital image processing, and unbiased stereological sampling procedures is used to estimate the coordination number distribution in three-dimensional microstructures. The microgravity environment decreases the mean coordination number. However, hardly any isolated grains are observed in the specimens, liquid phase sintered in a microgravity environment. The effect of microgravity on the coordination numbers mainly resides in its effect on the mean coordination number. In all specimens, there is a strong correlation between grain size and coordination number, which can be expressed as [D{sub c}/{bar D}]{sup 2} = C/C{sub 0} where C{sub 0} is the mean coordination number, {bar D} the global average size of the tungsten grains, and D{sub c} the average size of only those grains which have coordination number C.

  15. Junction conditions in extended Teleparallel gravities

    SciTech Connect (OSTI)

    De la Cruz-Dombriz, Álvaro; Dunsby, Peter K.S.; Sáez-Gómez, Diego E-mail: peter.dunsby@uct.ac.za

    2014-12-01

    In the context of extended Teleparallel gravity theories, we address the issue of junction conditions required to guarantee the correct matching of different regions of spacetime. In the absence of shells/branes, these conditions turn out to be more restrictive than their counterparts in General Relativity as in other extended theories of gravity. In fact, the general junction conditions on the matching hypersurfaces depend on the underlying theory and a new condition on the induced tetrads in order to avoid delta-like distributions in the field equations. This result imposes strict consequences on the viability of standard solutions such as the Einstein-Straus-like construction. We find that the continuity of the scalar torsion is required in order to recover the usual General Relativity results.

  16. Hydrogen atom in Palatini theories of gravity

    E-Print Network [OSTI]

    Gonzalo J. Olmo

    2008-06-03

    We study the effects that the gravitational interaction of $f(R)$ theories of gravity in Palatini formalism has on the stationary states of the Hydrogen atom. We show that the role of gravity in this system is very important for lagrangians $f(R)$ with terms that grow at low curvatures, which have been proposed to explain the accelerated expansion rate of the universe. We find that new gravitationally induced terms in the atomic Hamiltonian generate a strong backreaction that is incompatible with the very existence of bound states. In fact, in the 1/R model, Hydrogen disintegrates in less than two hours. The universe that we observe is, therefore, incompatible with that kind of gravitational interaction. Lagrangians with high curvature corrections do not lead to such instabilities.

  17. Infrared modification of gravity from conformal symmetry

    E-Print Network [OSTI]

    Gegenberg, Jack; Seahra, Sanjeev S

    2015-01-01

    We reconsider a gauge theory of gravity in which the gauge group is the conformal group SO(4,2) and the action is of the Yang-Mills form, quadratic in the curvature. The resulting gravitational theory exhibits local conformal symmetry and reduces to Weyl-squared gravity under certain conditions. When the theory is linearized about flat spacetime, we find that matter which couples to the generators of special conformal transformations reproduces Newton's inverse square law. Conversely, matter which couples to generators of translations induces a constant and possibly repulsive force far from the source, which may be relevant for explaining the late time acceleration of the universe. The coupling constant of theory is dimensionless, which means that it is potentially renormalizable.

  18. Conceptual Aspects of Gauge/Gravity Duality

    E-Print Network [OSTI]

    de Haro, Sebastian; Butterfield, Jeremy

    2015-01-01

    We give an introductory review of gauge/gravity duality, and associated ideas of holography, emphasising the conceptual aspects. The opening Sections gather the ingredients, viz. anti-de Sitter spacetime, conformal field theory and string theory, that we need for presenting, in Section 5, the central and original example: Maldacena's AdS/CFT correspondence. Sections 6 and 7 develop the ideas of this example, also in applications to condensed matter systems, QCD, and hydrodynamics. Sections 8 and 9 discuss the possible extensions of holographic ideas to de Sitter spacetime and to black holes. Section 10 discusses the bearing of gauge/gravity duality on two philosophical topics: the equivalence of physical theories, and the idea that spacetime, or some features of it, are emergent.

  19. Flattened velocity dispersion profiles in Globular Clusters: Newtonian tides or modified gravity?

    E-Print Network [OSTI]

    X. Hernandez; M. A. Jimenez; C. Allen

    2012-10-22

    Over the past couple of years, a number of observational studies have confirmed the flattening of the radial velocity dispersion profiles for stars in various nearby globular clusters. As the projected radial coordinate is increased, a radius appears beyond which, the measured velocity dispersion ceases to drop and settles at a fixed value, $\\sigma_{\\infty}$. Under Newtonian gravity, this is explained by invoking tidal heating from the overall Milky Way potential on the outer, more loosely bound stars, of the globular clusters in question. From the point of view of modified gravity theories, such an outer flattening is expected on crossing the critical acceleration threshold $a_{0}$, beyond which, a transition to MONDian dynamics is expected, were equilibrium velocities cease to be a function of distance. In this paper we attempt to sort out between the above competing explanations, by looking at their plausibility in terms of an strictly empirical approach. We determine Newtonian tidal radii using masses accurately calculated through stellar population modelling, and hence independent of any dynamical assumptions, distances, size and orbital determinations for a sample of 16 globular clusters. We show that their Newtonian tidal radii at perigalacticon are generally larger that the radii at which the flattening in the velocity dispersion profiles occurs, by large factors of 4, on average. While this point makes the Newtonian tidal explanation suspect, it is found that the radii at which the flattening is observed on average correlate with the radii where the $a_{0}$ threshold is crossed, and that $\\sigma_{\\infty}$ values scale with the fourth root of the total masses, all features predicted under modified gravity theories.

  20. Gravity controlled anti-reverse rotation device

    DOE Patents [OSTI]

    Dickinson, Robert J. (Shaler Township, Allegheny County, PA); Wetherill, Todd M. (Lower Burrell, PA)

    1983-01-01

    A gravity assisted anti-reverse rotation device for preventing reverse rotation of pumps and the like. A horizontally mounted pawl is disposed to mesh with a fixed ratchet preventing reverse rotation when the pawl is advanced into intercourse with the ratchet by a vertically mounted lever having a lumped mass. Gravitation action on the lumped mass urges the pawl into mesh with the ratchet, while centrifugal force on the lumped mass during forward, allowed rotation retracts the pawl away from the ratchet.

  1. Regulation of flexible arms under gravity

    SciTech Connect (OSTI)

    De Luca, A.; Siciliano, B.

    1993-08-01

    A simple controller is presented for the regulation problem of robot arms with flexible links under gravity. It consists of a joint PD feedback plus a constant feedforward. Global asymptotic stability of the reference equilibrium state is shown under a structural assumption about link elasticity and a mild condition on the proportional gain. The result holds also in the absence of internal damping of the flexible arm. A numerical case study is presented.

  2. Charged Cylindrical Black Holes in Conformal Gravity

    E-Print Network [OSTI]

    Jackson Levi Said; Joseph Sultana; Kristian Zarb Adami

    2013-01-04

    Considering cylindrical topology we present the static solution for a charged black hole in conformal gravity. We show that unlike the general relativistic case there are two different solutions, both including a factor that when set to zero recovers the familiar static charged black string solution in Einstein's theory. This factor gives rise to a linear term in the potential that also features in the neutral case and may have significant ramifications for particle trajectories.

  3. Holographic Superconductivity with Gauss-Bonnet gravity

    E-Print Network [OSTI]

    Ruth Gregory

    2010-12-07

    I review recent work on holographic superconductivity with Einstein-Gauss-Bonnet gravity, and show how the critical temperature of the superconductor depends on both gravitational backreaction and the Gauss-Bonnet parameter, using both analytic and numerical arguments. I also review computations of the conductivity, finding the energy gap, and demonstrating that there is no universal gap ratio, $\\omega_g/T_c$, for these superconductors.

  4. Exact Gravity Dual of a Gapless Superconductor

    E-Print Network [OSTI]

    George Koutsoumbas; Eleftherios Papantonopoulos; George Siopsis

    2009-06-17

    A model of an exact gravity dual of a gapless superconductor is presented in which the condensate is provided by a charged scalar field coupled to a bulk black hole of hyperbolic horizon in asymptotically AdS spacetime. Below a critical temperature, the black hole acquires its hair through a phase transition while an electromagnetic perturbation of the background Maxwell field determines the conductivity of the boundary theory.

  5. Disformal Gravity Theories: A Jordan Frame Analysis

    E-Print Network [OSTI]

    Sakstein, Jeremy

    2015-01-01

    The late-time cosmology of disformal gravity theories is studied in the Jordan frame using both dynamical systems methods, and by finding approximate solutions. We find that, either the disformal effects are irrelevant, or the universe evolves towards a phantom phase where the equation of state of dark energy is $-3$, in strong tension with observations. There is a marginal case where the asymptotic state of the universe depends on the model parameters and de-Sitter solutions can be obtained.

  6. Critical regimes of internal gravity wave generation

    E-Print Network [OSTI]

    Vitaly V. Bulatov; Yuriy V. Vladimirov; Vasily A. Vakorin

    2005-11-27

    The problem of constructing an asymptotic representation of the solution of the internal gravity wave field exited by a source moving at a velocity close to the maximum group velocity of the individual wave mode is considered. For the critical regimes of individual mode generation the asymptotic representation of the solution obtained is expressed in terms of a zero-order Macdonald function. The results of numerical calculations based on the exact and asymptotic formulas are given.

  7. Neutron stars as laboratories for gravity physics

    SciTech Connect (OSTI)

    Deliduman, Cemsinan

    2014-01-01

    We study the structure of neutron stars in R+?R² gravity model with perturbative method. We obtain mass-radius relations for four representative equations of state (EoS). We find that, for |?|~10? cm², the results differ substantially from the results of general relativity. The effects of modified gravity are seen as mimicking a stiff or soft EoS for neutron stars depending upon whether ? is negative or positive, respectively. Some of the soft EoS that are excluded within the framework of general relativity can be reconciled for certain values of ? of this order with the 2 solar mass neutron star recently observed. Indeed, if the EoS is ever established to be soft, modified gravity of the sort studied here may be required to explain neutron star masses as large as 2 M{sub ?}. The associated length scale ?(?)~10? cm is of the order of the the typical radius of neutron stars implying that this is the smallest value we could find by using neutron stars as a probe. We thus conclude that the true value of ? is most likely much smaller than 10? cm².

  8. Cosmology in general massive gravity theories

    SciTech Connect (OSTI)

    Comelli, D.; Nesti, F.; Pilo, L. E-mail: fabrizio.nesti@aquila.infn.it

    2014-05-01

    We study the cosmological FRW flat solutions generated in general massive gravity theories. Such a model are obtained adding to the Einstein General Relativity action a peculiar non derivative potentials, function of the metric components, that induce the propagation of five gravitational degrees of freedom. This large class of theories includes both the case with a residual Lorentz invariance as well as the case with rotational invariance only. It turns out that the Lorentz-breaking case is selected as the only possibility. Moreover it turns out that that perturbations around strict Minkowski or dS space are strongly coupled. The upshot is that even though dark energy can be simply accounted by massive gravity modifications, its equation of state w{sub eff} has to deviate from -1. Indeed, there is an explicit relation between the strong coupling scale of perturbations and the deviation of w{sub eff} from -1. Taking into account current limits on w{sub eff} and submillimiter tests of the Newton's law as a limit on the possible strong coupling scale, we find that it is still possible to have a weakly coupled theory in a quasi dS background. Future experimental improvements on short distance tests of the Newton's law may be used to tighten the deviation of w{sub eff} form -1 in a weakly coupled massive gravity theory.

  9. Emergent gravity and ether-drift experiments

    E-Print Network [OSTI]

    M. Consoli; L. Pappalardo

    2010-05-04

    According to several authors, gravity might be a long-wavelength phenomenon emerging in some 'hydrodynamic limit' from the same physical, flat-space vacuum viewed as a form of superfluid medium. In this framework, light might propagate in an effective acoustic geometry and exhibit a tiny anisotropy that could be measurable in the present ether-drift experiments. By accepting this view of the vacuum, one should also consider the possibility of sizeable random fluctuations of the signal that reflect the stochastic nature of the underlying `quantum ether' and could be erroneously interpreted as instrumental noise. To test the present interpretation, we have extracted the mean amplitude of the signal from various experiments with different systematics, operating both at room temperature and in the cryogenic regime. They all give the same consistent value = O (10^{-15}) which is precisely the magnitude expected in an emergent-gravity approach, for an apparatus placed on the Earth's surface. Since physical implications could be substantial, it would be important to obtain more direct checks from the instantaneous raw data and, possibly, with new experimental set-ups operating in gravity-free environments.

  10. Abelian-Higgs strings in Rastall gravity

    E-Print Network [OSTI]

    Eugenio R. Bezerra de Mello; Julio C. Fabris; Betti Hartmann

    2015-04-02

    In this paper we analyze Abelian-Higgs strings in a phenomenological model that takes quantum effects in curved space-time into account. This model, first introduced by Rastall, cannot be derived from an action principle. We formulate phenomenological equations of motion under the guiding principle of minimal possible deformation of the standard equations. We construct string solutions that asymptote to a flat space-time with a deficit angle by solving the set of coupled non-linear ordinary differential equations numerically. Decreasing the Rastall parameter from its Einstein gravity value we find that the deficit angle of the space-time increases and becomes equal to $2\\pi$ at some critical value of this parameter that depends on the remaining couplings in the model. For smaller values the resulting solutions are supermassive string solutions possessing a singularity at a finite distance from the string core. Assuming the Higgs boson mass to be on the order of the gauge boson mass we find that also in Rastall gravity this happens only when the symmetry breaking scale is on the order of the Planck mass. We also observe that for specific values of the parameters in the model the energy per unit length becomes proportional to the winding number, i.e. the degree of the map $S^1 \\rightarrow S^1$. Unlike in the BPS limit in Einstein gravity, this is, however, not connect to an underlying mathematical structure, but rather constitutes a would-be-BPS bound.

  11. Cosmology with Coupled Gravity and Dark Energy

    E-Print Network [OSTI]

    Ti-Pei Li

    2015-01-13

    Dark energy is a fundamental constituent of our universe, its status in the cosmological field equation should be equivalent to that of gravity. Here we construct a dark energy and matter gravity coupling (DEMC) model of cosmology in a way that dark energy and gravity are introduced into the cosmological field equation in parallel with each other from the beginning. The DEMC universe possesses a composite symmetry from global Galileo invariance and local Lorentz invariance. The observed evolution of the universe expansion rate at redshift z>1 is in tension with the standard LCDM model, but can be well predicted by the DEMC model from measurements of only nearby epochs. The so far most precise measured expansion rate at high z is quite a bit slower than the expectations from LCDM, but remarkably consistent with that from DEMC. It is hoped that the DEMC scenario can also help to solve other existing challenges to cosmology: large scale anomalies in CMB maps and large structures up to about 10^3 Mpc of a quasar group. The DEMC universe is a well defined mechanical system. From measurements we can quantitatively evaluate its total rest energy, present absolute radius and expanding speed.

  12. Quantum Gravito-Optics: A Light Route from Semiclassical Gravity to Quantum Gravity

    E-Print Network [OSTI]

    Unnikrishnan, C S

    2015-01-01

    Quantum gravity remains an elusive theory, in spite of our thorough understanding of the quantum theory and the general theory of relativity separately, presumably due to the lack of any observational clues. We argue that the theory of quantum gravity has a strong constraining anchor in the sector of gravitational radiation ensuring reliable physical clues, albeit in a limited observable form. In particular, all types of gravitational waves expected to be observable in LIGO-like advanced detectors are fully quantum mechanical states of radiation. Exact equivalence of the full quantum gravity theory with the familiar semiclassical theory is ensured in the radiation sector, in most real situations where the relevant quantum operator functions are normal ordered, by the analogue of the optical equivalence theorem in quantum optics. We show that this is indeed the case for detection of the waves from a massive binary system, a single gravitational atom, that emits coherent radiation. The idea of quantum-gravitati...

  13. Supporting data for: "The Lifetime of Android API vulnerabilities:case study on the JavaScript-to-Java interface"

    E-Print Network [OSTI]

    Thomas, Daniel R.; Coudray, Thomas; Sutcliffe, Tom

    2015-05-26

    _norm(vulnerable, total_file, condition, prefix, installed, prob, vulnerability_discovered, data_collected): norm_file = '{prefix}_{condition}_{installed}_{prob}-norm.csv'.format( prefix=prefix, condition=condition, prob=prob, installed=installed) with open... (total_file) as f: total = count_total(f) norm = OrderedDict() averagable_values = [] for day, count in vulnerable.items(): normed_value = count / total[day] if day >= vulnerability_discovered and day = data_collected: averagable_values.append(normed_value) norm...

  14. Rapid gravity and gravity gradiometry terrain correction via adaptive quadtree mesh discretization Kristofer Davis, M. Andy Kass, and Yaoguo Li, Center for Gravity, Electrical and Magnetic Studies, Colorado School

    E-Print Network [OSTI]

    Kristofer Davis, M. Andy Kass, and Yaoguo Li, Center for Gravity, Electrical and Magnetic Studies, Colorado

  15. Black Holes in Gauss-Bonnet Gravity's Rainbow

    E-Print Network [OSTI]

    Seyed Hossein Hendi; Mir Faizal

    2015-08-08

    In this paper, we will generalize the Gauss-Bonnet gravity to an energy dependent Gauss-Bonnet theory of gravity, which we shall call as the Gauss-Bonnet gravity's rainbow. We will also couple this theory to a Maxwell's theory. We will analyze black hole solutions in this energy dependent Gauss-Bonnet gravity's rainbow. We will calculate the modifications to the thermodynamics of black holes in the Gauss-Bonnet's gravity's rainbow. We will demonstrate that even though the thermodynamics of the black holes get modified in the Gauss-Bonnet gravity's rainbow, the first law of thermodynamics still holds for this modified thermodynamics. We will also comment on the thermal stability of the black hole solutions in this theory.

  16. Testing alternative theories of gravity using the Sun

    E-Print Network [OSTI]

    Jordi Casanellas; Paolo Pani; Ilídio Lopes; Vitor Cardoso

    2011-10-20

    We propose a new approach to test possible corrections to Newtonian gravity using solar physics. The high accuracy of current solar models and new precise observations allow one to constrain corrections to standard gravity at unprecedented levels. Our case study is Eddington-inspired gravity, an attractive modified theory of gravity which results in non-singular cosmology and collapse. The theory is equivalent to standard gravity in vacuum, but it sensibly differs from it within matter, for instance it affects the evolution and the equilibrium structure of the Sun, giving different core temperature profiles, deviations in the observed acoustic modes and in solar neutrino fluxes. Comparing the predictions from a modified solar model with observations, we constrain the coupling parameter of the theory, |kappa_g| < 3x10^5 m^5 s^2 / kg. Our results show that the Sun can be used to efficiently constraint alternative theories of gravity.

  17. Average Stumpage Prices Measured in Price per Ton for Forest Products Large Pine Sawtimber Small Pine Sawtimber Hardwood Sawtimber

    E-Print Network [OSTI]

    Average Stumpage Prices Measured in Price per Ton for Forest Products Large Pine Sawtimber Small Pine Sawtimber Hardwood Sawtimber Year Unweighte d Average Prices Weighted Average Prices Average of Unweighted and Weighted Prices Unweighted Average Prices Weighted Average Prices Average of Unweighted

  18. Average Stumpage Prices Measured in Price per Ton for Forest Products Large Pine Sawtimber Small Pine Sawtimber Hardwood Sawtimber

    E-Print Network [OSTI]

    Average Stumpage Prices Measured in Price per Ton for Forest Products Large Pine Sawtimber Small Pine Sawtimber Hardwood Sawtimber Year Unweighted Average Prices Weighted Average Prices Average of Unweighted and Weighted Prices Unweighted Average Prices Weighted Average Prices Average of Unweighted

  19. Average Stumpage Prices Measured in Price per Ton for Forest Products Large Pine Sawtimber Small Pine Sawtimber Hardwood Sawtimber

    E-Print Network [OSTI]

    Average Stumpage Prices Measured in Price per Ton for Forest Products Large Pine Sawtimber Small Pine Sawtimber Hardwood Sawtimber Year Unweighted Average Prices Weighted Average Prices Simple average of Unweighted and Weighted Prices Unweighted Average Prices Weighted Average Prices Simple average of Unweighted

  20. Fab 5: noncanonical kinetic gravity, self tuning, and cosmic acceleration

    SciTech Connect (OSTI)

    Appleby, Stephen A.; Linder, Eric V. [Institute for the Early Universe WCU, Ewha Womans University, Seoul (Korea, Republic of); Felice, Antonio De, E-mail: stephen.appleby@ewha.ac.kr, E-mail: adefelic@gmail.com, E-mail: evlinder@lbl.gov [ThEP's CRL, NEP, The Institute for Fundamental Study, Naresuan University, Phitsanulok 65000 (Thailand)

    2012-10-01

    We investigate circumstances under which one can generalize Horndeski's most general scalar-tensor theory of gravity. Specifically we demonstrate that a nonlinear combination of purely kinetic gravity terms can give rise to an accelerating universe without the addition of extra propagating degrees of freedom on cosmological backgrounds, and exhibit self tuning to bring a large cosmological constant under control. This nonlinear approach leads to new properties that may be instructive for exploring the behaviors of gravity.

  1. Solar System experiments do not yet veto modified gravity models

    E-Print Network [OSTI]

    Valerio Faraoni

    2006-07-05

    The dynamical equivalence between modified and scalar-tensor gravity theories is revisited and it is concluded that it breaks down in the limit to general relativity. A gauge-independent analysis of cosmological perturbations in both classes of theories lends independent support to this conclusion. As a consequence, the PPN formalism of scalar-tensor gravity and Solar System experiments do not veto modified gravity, as previously thought.

  2. Action in the Entropic Revolution of Newtonian Gravity

    E-Print Network [OSTI]

    Joakim Munkhammar

    2010-05-17

    The theory of gravity has undergone somewhat of a revolution lately. Gravity is no longer a fundamental force it seems, but rather an effect of holographic entropy. Building on the works by Jacobsson, Padmanabhan and Verlinde we review the concept of Newtonian gravity as an entropic force and discuss a possible general action approach to Verlinde's theory. We also discuss some open problems and future prospects of Verlinde's approach.

  3. ZEOLITE CATALYSIS - TECHNOLOGY

    E-Print Network [OSTI]

    Heinemann, Heinz

    2013-01-01

    and after Hydrodewaxing with 2SH-5 Virgin heavy gas oil MMDWprocessed heavy gas oil Properties Gravity, API Pour point,

  4. MediaWiki API

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    euquery empty to list all external links Can be empty, or One value: http, https, ftp, irc, gopher, telnet, nntp, worldwind, mailto, news, svn, git, mms Default: euquery - Search...

  5. MediaWiki API

    Open Energy Info (EERE)

    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 QA:QAsource History ViewMayo, Maryland: Energy Resources Jump to:Electric Coop, IncSouthVirginia:Medford, Maine:xml

  6. Web Service Interface (API)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking WithTelecentricN AProject AssessmentWe theBrowser

  7. LTB universes as alternatives to dark energy: does positive averaged acceleration imply positive cosmic acceleration?

    E-Print Network [OSTI]

    Antonio Enea Romano

    2007-01-27

    We show that positive averaged acceleration obtained in LTB models through spatial averaging can require integration over a region beyond the event horizon of the central observer. We provide an example of a LTB model with positive averaged acceleration in which the luminosity distance does not contain information about the entire spatially averaged region, making the averaged acceleration unobservable. Since the cosmic acceleration is obtained from fitting the observed luminosity distance to a FRW model we conclude that in general a positive averaged acceleration in LTB models does not imply a positive FRW cosmic acceleration.

  8. LTB universes as alternatives to dark energy: does positive averaged acceleration imply positive cosmic acceleration?

    E-Print Network [OSTI]

    Romano, A E

    2006-01-01

    We show that positive averaged acceleration obtained in LTB models through spatial averaging can require integration over a region beyond the event horizon of the central observer. We provide an example of a LTB model with positive averaged acceleration in which the luminosity distance does not contain information about the entire spatially averaged region, making the averaged acceleration unobservable. Since the cosmic acceleration is obtained from fitting the observed luminosity distance to a FRW model we conclude that in general a positive averaged acceleration in LTB models does not imply a positive FRW cosmic acceleration.

  9. Covariant Symplectic Structure and Conserved Charges of Topologically Massive Gravity

    E-Print Network [OSTI]

    Caner Nazaroglu; Yavuz Nutku; Bayram Tekin

    2011-06-07

    We present the covariant symplectic structure of the Topologically Massive Gravity and find a compact expression for the conserved charges of generic spacetimes with Killing symmetries.

  10. Lorentz Invariant phenomenological model of quantum gravity: A minimalistic presentation

    SciTech Connect (OSTI)

    Bonder, Yuri

    2012-08-24

    The purpose of this paper is to give a minimalistic and self-contained presentation of a Lorentz Invariant phenomenological model of Quantum Gravity.

  11. Gravity Survey of the Carson Sink - Data and Maps

    SciTech Connect (OSTI)

    Faulds, James E.

    2013-12-31

    A detailed gravity survey was carried out for the entire Carson Sink in western Nevada (Figure 1) through a subcontract to Zonge Engineering, Inc. The Carson Sink is a large composite basin containing three known, blind high?temperature geothermal systems (Fallon Airbase, Stillwater, and Soda Lake). This area was chosen for a detailed gravity survey in order to characterize the gravity signature of the known geothermal systems and to identify other potential blind systems based on the structural setting indicated by the gravity data. Data: Data were acquired at approximately 400, 800, and 1600 meter intervals for a total of 1,243 stations. The project location and station location points are presented in Figure 14. The station distribution for this survey was designed to complete regional gravity coverage in the Carson Sink area without duplication of available public and private gravity coverage. Gravity data were acquired using a Scintrex CG?5 gravimeter and a LaCoste and Romberg (L&R) Model?G gravimeter. The CG?5 gravity meter has a reading resolution of 0.001 milligals and a typical repeatability of less than 0.005 milligals. The L&R gravity meter has a reading resolution of 0.01 milligals and a typical repeatability of 0.02 milligals. The basic processing of gravimeter readings to calculate through to the Complete Bouguer Anomaly was made using the Gravity and Terrain Correction software version 7.1 for Oasis Montaj by Geosoft LTD. Results: The gravity survey of the Carson Sink yielded the following products. Project location and station location map (Figure 14). Complete Bouguer Anomaly @ 2.67 gm/cc reduction density. Gravity Complete Bouguer Anomaly at 2.50 g/cc Contour Map (Figure 15). Gravity Horizontal Gradient Magnitude Shaded Color Contour Map. Gravity 1st Vertical Derivative Color Contour Map. Interpreted Depth to Mesozoic Basement (Figure 16), incorporating drill?hole intercept values. Preliminary Interpretation of Results: The Carson Sink is a complex composite basin with several major depocenters (Figures 15 and 16). Major depocenters are present in the south?central, east?central, and northeastern parts of the basin. The distribution of gravity anomalies suggests a complex pattern of faulting in the subsurface of the basin, with many fault terminations, step?overs, and accommodation zones. The pattern of faulting implies that other, previously undiscovered blind geothermal systems are likely in the Carson Sink. The gravity survey was completed near the end of this project. Thus, more thorough analysis of the data and potential locations of blind geothermal systems is planned for future work.

  12. Cosmological singularities in Born-Infeld determinantal gravity...

    Office of Scientific and Technical Information (OSTI)

    Cosmological singularities in Born-Infeld determinantal gravity Citation Details In-Document Search This content will become publicly available on December 16, 2015 Title:...

  13. Dynamical stability of Minkowski space in higher order gravity

    E-Print Network [OSTI]

    Petr V. Tretyakov

    2015-05-19

    We discuss the Minkowski stability problem in modified gravity by using dynamical system approach. The method to investigate dynamical stability of Minkowski space was proposed. This method was applied for some modified gravity theories, such as $f(R)$ gravity, $f(R)+\\alpha R\\Box R$ gravity and scalar-tensor gravity models with non-minimal kinetic coupling. It was shown that in the case of $f(R)$ gravity Minkowski solution asymptotically stable in ghost-free ($f'>0$) and tachyon-free ($f">0$) theories in expanding Universe with respect to isotropic and basic anisotropic perturbations. In the case of higher order gravity with $\\alpha R\\Box R$ correction conditions of Minkowski stability with respect to isotropic perturbations significantly different: $f'(0)0$. And in the case of scalar-tensor gravity with non-minimal kinetic coupling Minkowski solution asymptotically stable in expanding Universe with respect to isotropic perturbations of metric. Moreover the developed method may be used for finding additional restrictions on parameters of different modified gravity theories.

  14. Ground Gravity Survey At Neal Hot Springs Geothermal Area (U...

    Open Energy Info (EERE)

    Ground Gravity Survey At Neal Hot Springs Geothermal Area (U.S. Geothermal Inc., 2007) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground...

  15. Geologic interpretation of gravity and magnetic data in the Salida...

    Open Energy Info (EERE)

    Geologic interpretation of gravity and magnetic data in the Salida region, Colorado Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Geologic...

  16. Unification of Gravity and Electromagnetism II A Geometric Theory

    E-Print Network [OSTI]

    Partha Ghose

    2015-02-11

    It is shown that unification of gravity and electromagnetism can be achieved using an affine non-symmetric connection $\\Gamma^\\lambda_{\\mu\

  17. Summary of Session A6: Alternative Theories of Gravity

    E-Print Network [OSTI]

    R. B. Mann

    1998-03-13

    This is a summary of the workshop A.6 on Alternative Theories of Gravity, prepared for the proceedings for the GR15 conference.

  18. Quantized gauge-affine gravity in the superfiber bundle approach

    E-Print Network [OSTI]

    A. Meziane; M. Tahiri

    2005-11-10

    The quantization of gauge-affine gravity within the superfiber bundle formalism is proposed. By introducing an even pseudotensorial 1-superform over a principal superfibre bundle with superconnection, we obtain the geometrical Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST transformations of the fields occurring in such a theory. Reducing the four-dimensional general affine group double-covering to the Poincare group double-covering we also find the BRST and anti-BRST transformations of the fields present in Einstein's gravity. Furthermore, we give a prescription leading to the construction of both BRST-invariant gauge-fixing action for gauge-affine gravity and Einstein's gravity.

  19. Exercise protocols during short-radius centrifugation for artificial gravity

    E-Print Network [OSTI]

    Edmonds, Jessica Leigh

    2008-01-01

    Long-duration spaceflight results in severe physiological deconditioning, threatening the success of interplanetary travel. Exercise combined with artificial gravity provided by centrifugation may be the comprehensive ...

  20. Bouguer gravity anomalies, depth to bedrock, and shallow temperature...

    Open Energy Info (EERE)

    Bouguer gravity anomalies, depth to bedrock, and shallow temperature in the Humboldt House geothermal area, Pershing County, Nevada Jump to: navigation, search OpenEI Reference...

  1. Ground Gravity Survey At Blue Mountain Geothermal Area (Fairbank...

    Open Energy Info (EERE)

    Ground Gravity Survey At Blue Mountain Geothermal Area (Fairbank Engineering Ltd, 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground...

  2. Probing hybrid modified gravity by stellar motion around Galactic Centre

    E-Print Network [OSTI]

    D. Borka; S. Capozziello; P. Jovanovi?; V. Borka Jovanovi?

    2015-04-29

    We consider possible signatures for the so called {\\it hybrid gravity} within the Galactic Central Parsec. This modified theory of gravity consists of a superposition of the metric Einstein-Hilbert Lagrangian with an $f(R)$ term constructed {\\it \\`{a} la Palatini } and can be easily reduced to an equivalent scalar-tensor theory. The present analysis is based on the S2 star orbital precession around the massive compact dark object at the Galactic Centre where the simulated orbits in hybrid modified gravity are compared with astronomical observations. These simulations result with strong constraints on the range of hybrid gravity interaction parameter $\\phi_0$ and show that its most probable value, in the case of S2 star, is around -0.0009 to -0.0002. At the same time, we are also able to obtain reliable constrains on the effective mass parameter $m_{\\phi}$ of hybrid modified gravity. Its most probable value, in the case of S2 star, is around -0.0034 to -0.0025. Furthermore, the hybrid gravity potential induces precession of S2 star orbit in the same direction as General Relativity. In previous papers, we considered other types of extended gravities, like metric power law $f(R)\\propto R^n$ gravity, inducing Yukawa and Sanders-like gravitational potentials, but it seems that hybrid gravity is the best among these models to explain different gravitational phenomena at different astronomical scales.

  3. Hydrogen Burning in Low Mass Stars Constrains Alternative Gravity Theories

    E-Print Network [OSTI]

    Jeremy Sakstein

    2015-10-30

    The most general scalar-tensor theories of gravity predict a weakening of the gravitational force inside astrophysical bodies. There is a minimum mass for hydrogen burning in stars that is set by the interplay of plasma physics and the theory of gravity. We calculate this for alternative theories of gravity, and find that it is always significantly larger than the general relativity prediction. The observation of several low mass Red Dwarf stars therefore rules out a large class of scalar-tensor gravity theories, and places strong constraints on the cosmological parameters appearing in the effective field theory of dark energy.

  4. Hydrogen Burning in Low Mass Stars Constrains Alternative Gravity Theories

    E-Print Network [OSTI]

    Jeremy Sakstein

    2015-10-20

    The most general scalar-tensor theories of gravity predict a weakening of the gravitational force inside astrophysical bodies. There is a minimum mass for hydrogen burning in stars that is set by the interplay of plasma physics and the theory of gravity. We calculate this for alternative theories of gravity, and find that it is always significantly larger than the general relativity prediction. The observation of several low mass Red Dwarf stars therefore rules out a large class of scalar-tensor gravity theories, and places strong constraints on the cosmological parameters appearing in the effective field theory of dark energy.

  5. Review of Lattice Supersymmetry and Gauge-Gravity Duality

    E-Print Network [OSTI]

    Joseph, Anosh

    2015-01-01

    We review the status of recent investigations on validating the gauge-gravity duality conjecture through numerical simulations of strongly coupled maximally supersymmetric thermal gauge theories. In the simplest setting, the gauge-gravity duality connects systems of D0-branes and black hole geometries at finite temperature to maximally supersymmetric gauged quantum mechanics at the same temperature. Recent simulations show that non-perturbative gauge theory results give excellent agreement with the quantum gravity predictions, thus proving strong evidence for the validity of the duality conjecture and more insight into quantum black holes and gravity.

  6. Review of Lattice Supersymmetry and Gauge-Gravity Duality

    E-Print Network [OSTI]

    Anosh Joseph

    2015-09-04

    We review the status of recent investigations on validating the gauge-gravity duality conjecture through numerical simulations of strongly coupled maximally supersymmetric thermal gauge theories. In the simplest setting, the gauge-gravity duality connects systems of D0-branes and black hole geometries at finite temperature to maximally supersymmetric gauged quantum mechanics at the same temperature. Recent simulations show that non-perturbative gauge theory results give excellent agreement with the quantum gravity predictions, thus proving strong evidence for the validity of the duality conjecture and more insight into quantum black holes and gravity.

  7. Ground Gravity Survey At San Francisco Volcanic Field Area (Warpinski...

    Open Energy Info (EERE)

    geologically mapped the target area, obtained rock samples for age dating and mineral chemistry, performed gravity and magnetic surveys, and integrated these results to identify...

  8. Parameterized post-Newtonian limit of Horndeski's gravity theory

    E-Print Network [OSTI]

    Manuel Hohmann

    2015-08-20

    We present a recent result on the parameterized post-Newtonian (PPN) limit of Horndeski's gravity theory and its consistency with solar system observations.

  9. Hydrogen Burning in Low Mass Stars Constrains Alternative Gravity Theories

    E-Print Network [OSTI]

    Sakstein, Jeremy

    2015-01-01

    The most general scalar-tensor theories of gravity predict a weakening of the gravitational force inside astrophysical bodies. There is a minimum mass for hydrogen burning in stars that is set by the interplay of plasma physics and the theory of gravity. We calculate this for alternative theories of gravity, and find that it is always significantly larger than the general relativity prediction. The observation of several low mass Red Dwarf stars therefore rules out a large class of scalar-tensor gravity theories, and places strong constraints on the cosmological parameters appearing in the effective field theory of dark energy.

  10. Interfacial gravity currents. I. Mixing and entrainment B. R. Sutherland

    E-Print Network [OSTI]

    Sutherland, Bruce

    Interfacial gravity currents. I. Mixing and entrainment B. R. Sutherland Department of Mathematical energy are compared with theories that neglect mixing and entrainment processes. As the middle layer

  11. Inversion of surface and borehole gravity with thresholding and density constraints Jiajia Sun and Yaoguo Li, Center for Gravity, Electrical and Magnetic Studies, Department of Geophysics, Colorado

    E-Print Network [OSTI]

    and Yaoguo Li, Center for Gravity, Electrical and Magnetic Studies, Department of Geophysics, Colorado School

  12. Effective Levi-Civita Dilaton theory from Metric Affine Dilaton Gravity

    E-Print Network [OSTI]

    R. Scipioni

    1999-05-25

    We show how a Metric Affine theory of Dilaton gravity can be reduced to an effective Riemannian Dilaton gravity model. A simple generalization of the Obukhov-Tucker-Wang theorem to Dilaton gravity is then presented.

  13. The JPL lunar gravity field to spherical harmonic degree 660 from the GRAIL Primary Mission

    E-Print Network [OSTI]

    Konopliv, Alex S.

    The lunar gravity field and topography provide a way to probe the interior structure of the Moon. Prior to the Gravity Recovery and Interior Laboratory (GRAIL) mission, knowledge of the lunar gravity was limited mostly to ...

  14. Fact #794: August 26, 2013 How Much Does an Average Vehicle Owner...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Each Year? Fact 794: August 26, 2013 How Much Does an Average Vehicle Owner Pay in Fuel Taxes Each Year? According to the Federal Highway Administration, the average fuel economy...

  15. Model comparison for automatic characterization and classification of average ERPs using visual oddball paradigm

    E-Print Network [OSTI]

    Polikar, Robi

    Model comparison for automatic characterization and classification of average ERPs using visual December 2008 Keywords: EEG ERP Attention P300 N200 Oddball Pattern recognition Linear discriminant responses from averaged event-related potentials (ERPs) along with identifying appropriate features

  16. Fact #638: August 30, 2010 Average Expenditure for a New Car...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    8: August 30, 2010 Average Expenditure for a New Car Declines in Relation to Family Earnings Fact 638: August 30, 2010 Average Expenditure for a New Car Declines in Relation to...

  17. Fact #715: February 20, 2012 The Average Age of Light Vehicles Continues to Rise

    Broader source: Energy.gov [DOE]

    The average age for cars and light trucks continues to rise as consumers hold onto their vehicles longer. Between 1995 and 2011, the average age for cars increased by 32% from 8.4 years to 11.1...

  18. Massive gravity on de Sitter and unique candidate for partially massless gravity

    SciTech Connect (OSTI)

    Rham, Claudia de; Renaux-Petel, Sébastien E-mail: srenaux@lpthe.jussieu.fr

    2013-01-01

    We derive the decoupling limit of Massive Gravity on de Sitter in an arbitrary number of space-time dimensions d. By embedding d-dimensional de Sitter into d+1-dimensional Minkowski, we extract the physical helicity-1 and helicity-0 polarizations of the graviton. The resulting decoupling theory is similar to that obtained around Minkowski. We take great care at exploring the partially massless limit and define the unique fully non-linear candidate theory that is free of the helicity-0 mode in the decoupling limit, and which therefore propagates only four degrees of freedom in four dimensions. In the latter situation, we show that a new Vainshtein mechanism is at work in the limit m{sup 2} ? 2H{sup 2} which decouples the helicity-0 mode when the parameters are different from that of partially massless gravity. As a result, there is no discontinuity between massive gravity and its partially massless limit, just in the same way as there is no discontinuity in the massless limit of massive gravity. The usual bounds on the graviton mass could therefore equivalently well be interpreted as bounds on m{sup 2}?2H{sup 2}. When dealing with the exact partially massless parameters, on the other hand, the symmetry at m{sup 2} = 2H{sup 2} imposes a specific constraint on matter. As a result the helicity-0 mode decouples without even the need of any Vainshtein mechanism.

  19. Quantum Gravito-Optics: A Light Route from Semiclassical Gravity to Quantum Gravity

    E-Print Network [OSTI]

    C. S. Unnikrishnan; George T. Gillies

    2015-08-03

    Quantum gravity remains an elusive theory, in spite of our thorough understanding of the quantum theory and the general theory of relativity separately, presumably due to the lack of any observational clues. We argue that the theory of quantum gravity has a strong constraining anchor in the sector of gravitational radiation ensuring reliable physical clues, albeit in a limited observable form. In particular, all types of gravitational waves expected to be observable in LIGO-like advanced detectors are fully quantum mechanical states of radiation. Exact equivalence of the full quantum gravity theory with the familiar semiclassical theory is ensured in the radiation sector, in most real situations where the relevant quantum operator functions are normal ordered, by the analogue of the optical equivalence theorem in quantum optics. We show that this is indeed the case for detection of the waves from a massive binary system, a single gravitational atom, that emits coherent radiation. The idea of quantum-gravitational optics can assist in guiding along the fuzzy roads to quantum gravity.

  20. Perturbations of nested branes with induced gravity

    SciTech Connect (OSTI)

    Sbisà, Fulvio; Koyama, Kazuya E-mail: kazuya.koyama@port.ac.uk

    2014-06-01

    We study the behaviour of weak gravitational fields in models where a 4D brane is embedded inside a 5D brane equipped with induced gravity, which in turn is embedded in a 6D spacetime. We consider a specific regularization of the branes internal structures where the 5D brane can be considered thin with respect to the 4D one. We find exact solutions corresponding to pure tension source configurations on the thick 4D brane, and study perturbations at first order around these background solutions. To perform the perturbative analysis, we adopt a bulk-based approach and we express the equations in terms of gauge invariant and master variables using a 4D scalar-vector-tensor decomposition. We then propose an ansatz on the behaviour of the perturbation fields when the thickness of the 4D brane goes to zero, which corresponds to configurations where gravity remains finite everywhere in the thin limit of the 4D brane. We study the equations of motion using this ansatz, and show that they give rise to a consistent set of differential equations in the thin limit, from which the details of the internal structure of the 4D brane disappear. We conclude that the thin limit of the ''ribbon'' 4D brane inside the (already thin) 5D brane is well defined (at least when considering first order perturbations around pure tension configurations), and that the gravitational field on the 4D brane remains finite in the thin limit. We comment on the crucial role of the induced gravity term on the 5D brane.

  1. Testing chameleon gravity with the Coma cluster

    SciTech Connect (OSTI)

    Terukina, Ayumu; Yamamoto, Kazuhiro; Lombriser, Lucas; Bacon, David; Koyama, Kazuya; Nichol, Robert C. E-mail: lucas.lombriser@port.ac.uk E-mail: david.bacon@port.ac.uk E-mail: bob.nichol@port.ac.uk

    2014-04-01

    We propose a novel method to test the gravitational interactions in the outskirts of galaxy clusters. When gravity is modified, this is typically accompanied by the introduction of an additional scalar degree of freedom, which mediates an attractive fifth force. The presence of an extra gravitational coupling, however, is tightly constrained by local measurements. In chameleon modifications of gravity, local tests can be evaded by employing a screening mechanism that suppresses the fifth force in dense environments. While the chameleon field may be screened in the interior of the cluster, its outer region can still be affected by the extra force, introducing a deviation between the hydrostatic and lensing mass of the cluster. Thus, the chameleon modification can be tested by combining the gas and lensing measurements of the cluster. We demonstrate the operability of our method with the Coma cluster, for which both a lensing measurement and gas observations from the X-ray surface brightness, the X-ray temperature, and the Sunyaev-Zel'dovich effect are available. Using the joint observational data set, we perform a Markov chain Monte Carlo analysis of the parameter space describing the different profiles in both the Newtonian and chameleon scenarios. We report competitive constraints on the chameleon field amplitude and its coupling strength to matter. In the case of f(R) gravity, corresponding to a specific choice of the coupling, we find an upper bound on the background field amplitude of |f{sub R0}| < 6 × 10{sup ?5}, which is currently the tightest constraint on cosmological scales.

  2. TIME-AVERAGING IN THE MARINE FOSSIL RECORD: OVERVIEW OF STRATEGIES AND

    E-Print Network [OSTI]

    , PALEOECOLOGY, BENTHIC, MARINE, TIME-AVERAGING. Rl~SUM]~ - Le raisonnement pal~ontologique qui a conduit ~ la

  3. Gravity duals for non-relativistic CFTs

    E-Print Network [OSTI]

    Koushik Balasubramanian; John McGreevy

    2008-08-01

    We attempt to generalize the AdS/CFT correspondence to non-relativistic conformal field theories which are invariant under Galilean transformations. Such systems govern ultracold atoms at unitarity, nucleon scattering in some channels, and more generally, a family of universality classes of quantum critical behavior. We construct a family of metrics which realize these symmetries as isometries. They are solutions of gravity with negative cosmological constant coupled to pressureless dust. We discuss realizations of the dust, which include a bulk superconductor. We develop the holographic dictionary and compute some two-point correlators. A strange aspect of the correspondence is that the bulk geometry has two extra noncompact dimensions.

  4. A new quasidilaton theory of massive gravity

    SciTech Connect (OSTI)

    Mukohyama, Shinji

    2014-12-01

    We present a new quasidilaton theory of Poincare invariant massive gravity, based on the recently proposed framework of matter coupling that makes it possible for the kinetic energy of the quasidilaton scalar to couple to both physical and fiducial metrics simultaneously. We find a scaling-type exact solution that expresses a self-accelerating de Sitter universe, and then analyze linear perturbations around it. It is shown that in a range of parameters all physical degrees of freedom have non-vanishing quadratic kinetic terms and are stable in the subhorizon limit, while the effective Newton's constant for the background is kept positive.

  5. A high frequency resonance gravity gradiometer

    SciTech Connect (OSTI)

    Bagaev, S. N.; Kvashnin, N. L.; Skvortsov, M. N.; Bezrukov, L. B.; Krysanov, V. A.; Oreshkin, S. I.; Motylev, A. M.; Popov, S. M.; Samoilenko, A. A.; Yudin, I. S.; Rudenko, V. N.

    2014-06-15

    A new setup OGRAN—the large scale opto-acoustical gravitational detector is described. As distinguished from known gravitational bar detectors it uses the optical interferometrical readout for registering weak variations of gravity gradient at the kilohetz frequency region. At room temperature, its sensitivity is limited only by the bar Brownian noise at the bandwidth close to 100 Hz. It is destined for a search for rare events—gravitational pulses coincident with signals of neutrino scintillator (BUST) in the deep underground of Baksan Neutrino Observatory of INR RAS.

  6. Loop Quantum Gravity: An Inside View

    E-Print Network [OSTI]

    Thomas Thiemann

    2006-08-29

    This is a (relatively) non -- technical summary of the status of the quantum dynamics in Loop Quantum Gravity (LQG). We explain in detail the historical evolution of the subject and why the results obtained so far are non -- trivial. The present text can be viewed in part as a response to an article by Nicolai, Peeters and Zamaklar [hep-th/0501114]. We also explain why certain no go conclusions drawn from a mathematically correct calculation in a recent paper by Helling et al [hep-th/0409182] are physically incorrect.

  7. Confronting Dilaton-exchange gravity with experiments

    E-Print Network [OSTI]

    H. V. Klapdor-Kleingrothaus; H. Päs; U. Sarkar

    2000-08-16

    We study the experimental constraints on theories, where the equivalence principle is violated by dilaton-exchange contributions to the usual graviton-exchange gravity. We point out that in this case it is not possible to have any CPT violation and hence there is no constraint from the CPT violating measurements in the $K-$system. The most stringent bound is obtained from the $K_L - K_S$ mass difference. In contrast, neither neutrino oscillation experiments nor neutrinoless double beta decay imply significant constraints.

  8. Static wormholes in vacuum for conformal gravity

    E-Print Network [OSTI]

    Julio Oliva; David Tempo; Ricardo Troncoso

    2009-07-07

    A static spherically symmetric wormhole solution for conformal gravity in vacuum is found. The solution possesses a single integration constant which determines the size of the neck connecting two static homogeneous universes of constant spatial curvature. Time runs at different rates on each side of the neck, and depending on the value of the parameter, the wormhole can develop a cosmological horizon only at one side. It is shown that the wormholes correspond to the matching of different Einstein spacetimes by means of improper conformal transformations.

  9. Gamma Ray Burst Neutrinos Probing Quantum Gravity

    E-Print Network [OSTI]

    M. C. Gonzalez-Garcia; F. Halzen

    2006-11-28

    Very high energy, short wavelength, neutrinos may interact with the space-time foam predicted by theories of quantum gravity. They would propagate like light through a crystal lattice and be delayed, with the delay depending on the energy. This will appear to the observer as a violation of Lorenz invariance. Back of the envelope calculations imply that observations of neutrinos produced by gamma ray bursts may reach Planck-scale sensitivity. We revisit the problem considering two essential complications: the imprecise timing of the neutrinos associated with their poorly understood production mechanism in the source and the indirect nature of their energy measurement made by high energy neutrino telescopes.

  10. Linearization of Moffat's Symmetric Complex Metric Gravity

    E-Print Network [OSTI]

    Joakim Munkhammar

    2009-09-19

    In this paper we investigate a complex symmetric generalization of general relativity and in particular we investigate its linearized field equations. We begin by reviewing some basic definitions and structures in Moffat's symmetric complex metric field theory of gravity. We then move on to derive the linearized retarded complex field equations. In addition to this we also derive a linearization of Moffat's field equations based on the more rigorous Fermi coordinate approach. In conclusion it is shown that the linearized symmetric complex field equations leads to a complex form of gravitomagnetism. We also briefly review the gravitational wave equation from the source less linearized symmetric complex field equations and discuss some open problems.

  11. Gravity can be neither classical nor quantized

    E-Print Network [OSTI]

    Sabine Hossenfelder

    2012-12-03

    I argue that it is possible for a theory to be neither quantized nor classical. We should therefore give up the assumption that the fundamental theory which describes gravity at shortest distances must either be quantized, or quantization must emerge from a fundamentally classical theory. To illustrate my point I will discuss an example for a theory that is neither classical nor quantized, and argue that it has the potential to resolve the tensions between the quantum field theories of the standard model and general relativity.

  12. Null Energy Condition violations in bimetric gravity

    E-Print Network [OSTI]

    Baccetti, Valentina; Visser, Matt

    2012-01-01

    We consider the effective stress-energy tensors for the foreground and background sectors in ghost-free bimetric gravity. By considering the symmetries of the theory, we show that the foreground and background null energy conditions (NECs) are strongly anti-correlated. In particular, the NECs can only be simultaneously fulfilled when they saturate, corresponding to foreground and background cosmological constants. In all other situations, either the foreground or the background is subject to a NEC-violating contribution to the total stress-energy.

  13. A structural analysis of vehicle design responses to Corporate Average Fuel Economy policy

    E-Print Network [OSTI]

    Michalek, Jeremy J.

    A structural analysis of vehicle design responses to Corporate Average Fuel Economy policy Ching 2009 Accepted 29 August 2009 Keywords: Corporate Average Fuel Economy Energy policy Oligopolistic market Game theory Vehicle design a b s t r a c t The US Corporate Average Fuel Economy (CAFE

  14. On coupling NEC-violating matter to gravity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chatterjee, Saugata; Parikh, Maulik; van der Schaar, Jan Pieter

    2015-05-01

    We show that effective theories of matter that classically violate the null energy condition cannot be minimally coupled to Einstein gravity without being inconsistent with both string theory and black hole thermodynamics. We argue however that they could still be either non-minimally coupled or coupled to higher-curvature theories of gravity.

  15. Stochastic cosmology, theories of perturbations and Lifshitz gravity

    E-Print Network [OSTI]

    Khalatnikov, I M

    2015-01-01

    We review some works of E M Lifshitz connected with gravity and cosmology and also some later works, connected with his ideas. The main topics of this review are the stochastic cosmology of an anisotropic universe and of an isotropic universe with the scalar field, the quasi-isotropic (gradient) expansion in cosmology and Horava-Lifshitz gravity and cosmology.

  16. Gravity Dual for Cyclic Renormalization Group Flow without Conformal Invariance

    E-Print Network [OSTI]

    Yu Nakayama

    2011-07-21

    We construct a gravity dual for scale invariant but non-conformal field theories with a cyclic renormalization group flow. A slight modification of our construction gives a gravity dual of discretely scale invariant field theories. The underlying gravitational theory breaks the null energy condition.

  17. Disformal transformations, veiled General Relativity and Mimetic Gravity

    SciTech Connect (OSTI)

    Deruelle, Nathalie; Rua, Josephine E-mail: rua@cbpf.br

    2014-09-01

    In this Note we show that Einstein's equations for gravity are generically invariant under ''disformations''. We also show that the particular subclass when this is not true yields the equations of motion of ''Mimetic Gravity''. Finally we give the ''mimetic'' generalization of the Schwarzschild solution.

  18. Bimetric gravity doubly coupled to matter: theory and cosmological implications

    SciTech Connect (OSTI)

    Akrami, Yashar; Koivisto, Tomi S.; Mota, David F.; Sandstad, Marit E-mail: t.s.koivisto@astro.uio.no E-mail: marit.sandstad@astro.uio.no

    2013-10-01

    A ghost-free theory of gravity with two dynamical metrics both coupled to matter is shown to be consistent and viable. Its cosmological implications are studied, and the models, in particular in the context of partially massless gravity, are found to explain the cosmic acceleration without resorting to dark energy.

  19. Ph.D.Thesis Binary inversion of gravity

    E-Print Network [OSTI]

    Ph.D.Thesis Binary inversion of gravity data for salt imaging Richard A. Krahenbuhl Center of Mines Golden, CO 80401 http://www.geophysics.mines.edu/cgem CGEM #12;#12;Ph.D.Thesis Binary inversion) #12;#12;BINARY INVERSION OF GRAVITY DATA FOR SALT IMAGING by Richard A. Krahenbuhl #12;#12;ii A thesis

  20. Simulation of Gravity Flow of Granular Materials in Silos

    E-Print Network [OSTI]

    and handle vast quantities of raw materials in granular form. The material is usually retrieved throughSimulation of Gravity Flow of Granular Materials in Silos Pierre A. Gremaud1 and John V. Matthews1 materials in silos under the action of gravity is considered. In the case of a Mohr-Coulomb material

  1. Synoptic Responses to Mountain Gravity Waves Encountering Directional Critical Levels

    E-Print Network [OSTI]

    Lott, Francois

    Synoptic Responses to Mountain Gravity Waves Encountering Directional Critical Levels ARMEL MARTIN the synoptic response to mountain gravity waves (GWs) absorbed at directional critical levels. The model in the midtroposphere. First, the authors consider the case of an idealized mountain range such that the orographic

  2. Gravity waves excited by jets: Propagation versus generation R. Plougonven

    E-Print Network [OSTI]

    Plougonven, Riwal

    Gravity waves excited by jets: Propagation versus generation R. Plougonven School of Mathematics imposed by the generation mechanism. In proceeding so, effects due to the propagation of the waves through in consequence that the gravity waves are generated in the jet-exit region. [4] To date, such arguments have

  3. 18 Maple Syrup Digest HIGH VACUUM IN GRAVITY TUBING

    E-Print Network [OSTI]

    Hayden, Nancy J.

    where elec- tricity is not available, time needed for maintenance of a pump and extractor gravity tubing, or tubing without the use of a pump, to be a poor substitute for a modern system with a pump, extractor, and the latest tubing arrangement. Sap yields from gravity systems are often half

  4. The Gravity of Annual Freight and Logistics Symposium

    E-Print Network [OSTI]

    Minnesota, University of

    The Gravity of Logistics 17th Annual Freight and Logistics Symposium A Summary Report | December 6 to those who want them --the "gravity" of logistics--depends on infrastructure that can support and sustainth Annual State of Logistics Report--IsThis the New Normal? Rosalyn Wilson, Senior Business Analyst

  5. Multimodal standing gravity waves: a completely resonant system.

    E-Print Network [OSTI]

    Iooss, Gérard

    Multimodal standing gravity waves: a completely resonant system. G´erard Iooss , Pavel Plotnikov@hydro.nsc.ru Abstract The standing gravity wave problem on an infinitely deep fluid layer is considered under the form be expanded in powers of amplitude is then given up to order 2 . Key words: nonlinear water waves, standing

  6. f(T,T) gravity and cosmology

    SciTech Connect (OSTI)

    Harko, Tiberiu; Lobo, Francisco S.N.; Otalora, G.; Saridakis, Emmanuel N. E-mail: flobo@cii.fc.ul.pt

    2014-12-01

    We present an extension of f(T) gravity, allowing for a general coupling of the torsion scalar T with the trace of the matter energy-momentum tensor T. The resulting f(T,T) theory is a new modified gravity, since it is different from all the existing torsion or curvature based constructions. Applied to a cosmological framework, it leads to interesting phenomenology. In particular, one can obtain a unified description of the initial inflationary phase, the subsequent non-accelerating, matter-dominated expansion, and then the transition to a late-time accelerating phase. Additionally, the effective dark energy sector can be quintessence or phantom-like, or exhibit the phantom-divide crossing during the evolution. Moreover, in the far future the universe results either to a de Sitter exponential expansion, or to eternal power-law accelerated expansions. Finally, a detailed study of the scalar perturbations at the linear level reveals that f(T,T) cosmology can be free of ghosts and instabilities for a wide class of ansatzes and model parameters.

  7. Vacuum energy: quantum hydrodynamics vs quantum gravity

    E-Print Network [OSTI]

    G. E. Volovik

    2005-09-09

    We compare quantum hydrodynamics and quantum gravity. They share many common features. In particular, both have quadratic divergences, and both lead to the problem of the vacuum energy, which in the quantum gravity transforms to the cosmological constant problem. We show that in quantum liquids the vacuum energy density is not determined by the quantum zero-point energy of the phonon modes. The energy density of the vacuum is much smaller and is determined by the classical macroscopic parameters of the liquid including the radius of the liquid droplet. In the same manner the cosmological constant is not determined by the zero-point energy of quantum fields. It is much smaller and is determined by the classical macroscopic parameters of the Universe dynamics: the Hubble radius, the Newton constant and the energy density of matter. The same may hold for the Higgs mass problem: the quadratically divergent quantum correction to the Higgs potential mass term is also cancelled by the microscopic (trans-Planckian) degrees of freedom due to thermodynamic stability of the whole quantum vacuum.

  8. Quantum Foam, Gravity and Gravitational Waves

    E-Print Network [OSTI]

    Cahill, R T

    2003-01-01

    The new information-theoretic Process Physics has shown that space is a quantum foam system with gravity being, in effect, an inhomogeneous in-flow of the quantum foam into matter. The theory predicts that absolute motion with respect to this system should be observable, and it is shown here that absolute motion has been detected in at least seven experiments. As well this experimental data also reveals the existence of a gravitational wave phenomena associated with the in-flow. It is shown that Galilean Relativity and Special Relativity are in fact compatible, contrary to current beliefs: absolute motion actually causes the special relativity effects. The new theory of gravity passes all the tests of the previous Newtonian and General Relativity theories, but in addition resolves the numerous gravitational anomalies such as the spiral galaxy `dark matter' effect, the absence of `dark matter' in elliptical galaxies, the inconsistencies in measuring G, the borehole g anomaly, and others. It is shown that Newto...

  9. Motion in alternative theories of gravity

    E-Print Network [OSTI]

    Gilles Esposito-Farese

    2009-05-15

    Although general relativity (GR) passes all present experimental tests with flying colors, it remains important to study alternative theories of gravity for several theoretical and phenomenological reasons that we recall in these lecture notes. The various possible ways of modifying GR are presented, and we notably show that the motion of massive bodies may be changed even if one assumes that matter is minimally coupled to the metric as in GR. This is illustrated with the particular case of scalar-tensor theories of gravity, whose Fokker action is discussed, and we also mention the consequences of the no-hair theorem on the motion of black holes. The finite size of the bodies modifies their motion with respect to pointlike particles, and we give a simple argument showing that the corresponding effects are generically much larger in alternative theories than in GR. We also discuss possible modifications of Newtonian dynamics (MOND) at large distances, which have been proposed to avoid the dark matter hypothesis. We underline that all the previous classes of alternatives to GR may a priori be used to predict such a phenomenology, but that they generically involve several theoretical and experimental difficulties.

  10. Scattering amplitudes in super-renormalizable gravity

    E-Print Network [OSTI]

    Pietro Donà; Stefano Giaccari; Leonardo Modesto; Leslaw Rachwal; Yiwei Zhu

    2015-06-15

    We explicitly compute the tree-level on-shell four-graviton amplitudes in four, five and six dimensions for local and weakly nonlocal gravitational theories that are quadratic in both, the Ricci and scalar curvature with form factors of the d'Alembertian operator inserted between. More specifically we are interested in renormalizable, super-renormalizable or finite theories. The scattering amplitudes for these theories turn out to be the same as the ones of Einstein gravity regardless of the explicit form of the form factors. As a special case the four-graviton scattering amplitudes in Weyl conformal gravity are identically zero. Using a field redefinition, we prove that the outcome is correct for any number of external gravitons (on-shell $n-$point functions) and in any dimension for a large class of theories. However, when an operator quadratic in the Riemann tensor is added in any dimension (with the exception of the Gauss-Bonnet term in four dimensions) the result is completely altered, and the scattering amplitudes depend on all the form factors introduced in the action.

  11. Scattering amplitudes in super-renormalizable gravity

    E-Print Network [OSTI]

    Donà, Pietro; Modesto, Leonardo; Rachwal, Leslaw; Zhu, Yiwei

    2015-01-01

    We explicitly compute the tree-level on-shell four-graviton amplitudes in four, five and six dimensions for local and weakly nonlocal gravitational theories that are quadratic in both, the Ricci and scalar curvature with form factors of the d'Alembertian operator inserted between. More specifically we are interested in renormalizable, super-renormalizable or finite theories. The scattering amplitudes for these theories turn out to be the same as the ones of Einstein gravity regardless of the explicit form of the form factors. As a special case the four-graviton scattering amplitudes in Weyl conformal gravity are identically zero. Using a field redefinition, we prove that the outcome is correct for any number of external gravitons (on-shell $n-$point functions) and in any dimension for a large class of theories. However, when an operator quadratic in the Riemann tensor is added in any dimension (with the exception of the Gauss-Bonnet term in four dimensions) the result is completely altered, and the scattering...

  12. New ground state for quantum gravity

    E-Print Network [OSTI]

    Joao Magueijo; Laura Bethke

    2012-07-03

    In this paper we conjecture the existence of a new "ground" state in quantum gravity, supplying a wave function for the inflationary Universe. We present its explicit perturbative expression in the connection representation, exhibiting the associated inner product. The state is chiral, dependent on the Immirzi parameter, and is the vacuum of a second quantized theory of graviton particles. We identify the physical and unphysical Hilbert sub-spaces. We then contrast this state with the perturbed Kodama state and explain why the latter can never describe gravitons in a de Sitter background. Instead, it describes self-dual excitations, which are composites of the positive frequencies of the right-handed graviton and the negative frequencies of the left-handed graviton. These excitations are shown to be unphysical under the inner product we have identified. Our rejection of the Kodama state has a moral tale to it: the semi-classical limit of quantum gravity can be the wrong path for making contact with reality (which may sometimes be perturbative but nonetheless fully quantum). Our results point towards a non-perturbative extension, and we present some conjectures on the nature of this hypothetical state.

  13. Cosmography of f(R) gravity

    E-Print Network [OSTI]

    Capozziello, S; Salzano, V

    2008-01-01

    It is nowadays accepted that the universe is undergoing a phase of accelerated expansion as tested by the Hubble diagram of Type Ia Supernovae (SNeIa) and several LSS observations. Future SNeIa surveys and other probes will make it possible to better characterize the dynamical state of the universe renewing the interest in cosmography which allows a model independent analysis of the distance - redshift relation. On the other hand, fourth order theories of gravity, also referred to as $f(R)$ gravity, have attracted a lot of interest since they could be able to explain the accelerated expansion without any dark energy. We show here how it is possible to relate the cosmographic parameters (namely the deceleration $q_0$, the jerk $j_0$, the snap $s_0$ and the lerk $l_0$ parameters) to the present day values of $f(R)$ and its derivatives $f^{(n)}(R) = d^nf/dR^n$ (with $n = 1, 2, 3$) thus offering a new tool to constrain such higher order models. Our analysis thus offers the possibility to relate the model independ...

  14. Cosmography of f(R) gravity

    E-Print Network [OSTI]

    S. Capozziello; V. F. Cardone; V. Salzano

    2008-07-08

    It is nowadays accepted that the universe is undergoing a phase of accelerated expansion as tested by the Hubble diagram of Type Ia Supernovae (SNeIa) and several LSS observations. Future SNeIa surveys and other probes will make it possible to better characterize the dynamical state of the universe renewing the interest in cosmography which allows a model independent analysis of the distance - redshift relation. On the other hand, fourth order theories of gravity, also referred to as $f(R)$ gravity, have attracted a lot of interest since they could be able to explain the accelerated expansion without any dark energy. We show here how it is possible to relate the cosmographic parameters (namely the deceleration $q_0$, the jerk $j_0$, the snap $s_0$ and the lerk $l_0$ parameters) to the present day values of $f(R)$ and its derivatives $f^{(n)}(R) = d^nf/dR^n$ (with $n = 1, 2, 3$) thus offering a new tool to constrain such higher order models. Our analysis thus offers the possibility to relate the model independent results coming from cosmography to the theoretically motivated assumptions of $f(R)$ cosmology.

  15. Non-trivial 2+1-Dimensional Gravity

    E-Print Network [OSTI]

    D. R. Grigore; G. Scharf

    2010-08-07

    We analyze 2+1-dimensional gravity in the framework of quantum gauge theory. We find that Einstein gravity has a trivial physical subspace which reflects the fact that the classical solution in empty space is flat. Therefore we study massive gravity which is not trivial. In the limit of vanishing graviton mass we obtain a non-trivial massless theory different from Einstein gravity. We derive the interaction from descent equations and obtain the cosmological topologically massive gravity. However, in addition to Einstein and Chern-Simons coupling we need coupling to fermionic ghost and anti-ghost fields and to a vector-graviton field with the same mass as the graviton.

  16. Massive gravitational waves in Chern-Simons modified gravity

    SciTech Connect (OSTI)

    Myung, Yun Soo; Moon, Taeyoon E-mail: tymoon@inje.ac.kr

    2014-10-01

    We consider the nondynamical Chern-Simons (nCS) modified gravity, which is regarded as a parity-odd theory of massive gravity in four dimensions. We first find polarization modes of gravitational waves for ?=x/? in nCS modified gravity by using the Newman-Penrose formalism where the null complex tetrad is necessary to specify gravitational waves. We show that in the Newman–Penrose formalism, the number of polarization modes is one in addition to an unspecified ?{sub 4}, implying three degrees of freedom for ?=x/?. This compares with two for a canonical embedding of ?=t/?. Also, if one introduces the Ricci tensor formalism to describe a massive graviton arising from the nCS modified gravity, one finds one massive mode after making second-order wave equations, which is compared to five found from the parity-even Einstein–Weyl gravity.

  17. Scalars, Vectors and Tensors from Metric-Affine Gravity

    E-Print Network [OSTI]

    Karahan, Canan N; Demir, Durmus A

    2011-01-01

    The metric-affine gravity provides a useful framework for analyzing gravitational dynamics since it treats metric tensor and affine connection as fundamentally independent variables. In this work, we show that, a metric-affine gravity theory composed of the invariants formed from non-metricity, torsion and curvature tensors decomposes exhaustively into a theory of scalar, vector and tensor fields. These fields are natural candidates for the ones needed by various cosmological phenomena. Indeed, we show that the model accommodates TeVeS gravity (relativistic modified gravity theory), vector inflation, and aether-like models. Detailed analyses of these and other phenomena can lead to a standard metric-affine gravity model encoding scalars, vectors and tensors necessitated by cosmology.

  18. Scalars, Vectors and Tensors from Metric-Affine Gravity

    E-Print Network [OSTI]

    Canan N. Karahan; Asli Altas; Durmus A. Demir

    2013-02-02

    The metric-affine gravity provides a useful framework for analyzing gravitational dynamics since it treats metric tensor and affine connection as fundamentally independent variables. In this work, we show that, a metric-affine gravity theory composed of the invariants formed from non-metricity, torsion and curvature tensors can be decomposed into a theory of scalar, vector and tensor fields. These fields are natural candidates for the ones needed by various cosmological and other phenomena. Indeed, we show that the model accommodates TeVeS gravity (relativistic modified gravity theory), vector inflation, and aether-like models. Detailed analyses of these and other phenomena can lead to a standard metric-affine gravity model encoding scalars, vectors and tensors.

  19. Testing Chern-Simons modified gravity with orbiting superconductive gravity gradiometers --- The non-dynamical formulation

    E-Print Network [OSTI]

    Qiang, Li-E

    2015-01-01

    High precision Superconductivity Gravity Gradiometers (SGG) are powerful tools for relativistic experiments. In this paper, we work out the tidal signals in non-dynamical Chern-Simons modified gravity, which could be measured by orbiting SGGs around Earth. We find that, with proper orientations of multi-axes SGGs, the tidal signals from the Chern-Simons modification can be isolated in the combined data of different axes. Furthermore, for three-axes SGGs, such combined data is the trace of the total tidal matrix, which is invariant under the rotations of SGG axes and thus free from axis pointing errors. Following nearly circular orbits, the tests of the parity-violating Chern-Simons modification and the measurements of the gravitomagnetic sector in parity-conserving metric theories can be carried out independently in the same time. A first step analysis on noise sources is also included.

  20. Testing Chern-Simons modified gravity with orbiting superconductive gravity gradiometers --- The non-dynamical formulation

    E-Print Network [OSTI]

    Li-E Qiang; Peng Xu

    2015-02-16

    High precision Superconductivity Gravity Gradiometers (SGG) are powerful tools for relativistic experiments. In this paper, we work out the tidal signals in non-dynamical Chern-Simons modified gravity, which could be measured by orbiting SGGs around Earth. We find that, with proper orientations of multi-axes SGGs, the tidal signals from the Chern-Simons modification can be isolated in the combined data of different axes. Furthermore, for three-axes SGGs, such combined data is the trace of the total tidal matrix, which is invariant under the rotations of SGG axes and thus free from axis pointing errors. Following nearly circular orbits, the tests of the parity-violating Chern-Simons modification and the measurements of the gravitomagnetic sector in parity-conserving metric theories can be carried out independently in the same time. A first step analysis on noise sources is also included.

  1. A length operator for canonical quantum gravity

    E-Print Network [OSTI]

    T. Thiemann

    1996-06-29

    We construct an operator that measures the length of a curve in four-dimensional Lorentzian vacuum quantum gravity. We work in a representation in which a $SU(2)$ connection is diagonal and it is therefore surprising that the operator obtained after regularization is densely defined, does not suffer from factor ordering singularities and does not require any renormalization. We show that the length operator admits self-adjoint extensions and compute part of its spectrum which like its companions, the volume and area operators already constructed in the literature, is purely discrete and roughly is quantized in units of the Planck length. The length operator contains full and direct information about all the components of the metric tensor which faciliates the construction of a new type of weave states which approximate a given classical 3-geometry.

  2. Bi-metric Gravity and "Dark Matter"

    E-Print Network [OSTI]

    I. T. Drummond

    2000-08-18

    We present a bi-metric theory of gravity containing a length scale of galactic size. For distances less than this scale the theory satisfies the standard tests of General Relativity. For distances greater than this scale the theory yields an effective gravitational constant much larger than the locally observed value of Newton's constant. The transition from one regime to the other through the galactic scale can explain the observed rotation curves of galaxies and hence the effects normally attributed to the presence of dark matter. Phenomena on an extragalactic scale such as galactic clusters and the expansion of the universe are controlled by the enhanced gravitational coupling. This provides an explanation of the missing matter normally invoked to account for the observed value of Hubble's constant in relation to observed matter.

  3. Mixing lengths scaling in a gravity flow

    SciTech Connect (OSTI)

    Ecke, Robert E [Los Alamos National Laboratory; Rivera, Micheal [Los Alamos National Laboratory; Chen, Jun [Los Alamos National Laboratory; Ecke, Robert E [Los Alamos National Laboratory

    2009-01-01

    We present an experimental study of the mixing processes in a gravity current. The turbulent transport of momentum and buoyancy can be described in a very direct and compact form by a Prandtl mixing length model [1]: the turbulent vertical fluxes of momentum and buoyancy are found to scale quadraticatly with the vertical mean gradients of velocity and density. The scaling coefficient is the square of the mixing length, approximately constant over the mixing zone of the stratified shear layer. We show in this paper how, in different flow configurations, this length can be related to the shear length of the flow {radical}({var_epsilon}/{partial_derivative}{sub z}u{sup 3}).

  4. Revisiting perturbations in extended quasidilaton massive gravity

    E-Print Network [OSTI]

    Lavinia Heisenberg

    2015-04-16

    In this work we study the theory of extended quasidilaton massive gravity together with the presence of matter fields. After discussing the homogeneous and isotropic fully dynamical background equations, which governs the exact expansion history of the universe, we consider small cosmological perturbations around these general FLRW solutions. The stability of tensor, vector and scalar perturbations on top of these general background solutions give rise to slightly different constraints on the parameters of the theory than those obtained in the approximative assumption of the late-time asymptotic form of the expansion history, which does not correspond to our current epoch. This opens up the possibility of stable FLRW solutions to be compared with current data on cosmic expansion with the restricted parameter space based on theoretical ground.

  5. Revisiting perturbations in extended quasidilaton massive gravity

    E-Print Network [OSTI]

    Heisenberg, Lavinia

    2015-01-01

    In this work we study the theory of extended quasidilaton massive gravity together with the presence of matter fields. After discussing the homogeneous and isotropic fully dynamical background equations, which governs the exact expansion history of the universe, we consider small cosmological perturbations around these general FLRW solutions. The stability of tensor, vector and scalar perturbations on top of these general background solutions give rise to slightly different constraints on the parameters of the theory than those obtained in the approximative assumption of the late-time asymptotic form of the expansion history, which does not correspond to our current epoch. This opens up the possibility of stable FLRW solutions to be compared with current data on cosmic expansion with the restricted parameter space based on theoretical ground.

  6. Nonsingular cosmology from evolutionary quantum gravity

    E-Print Network [OSTI]

    Francesco Cianfrani; Giovanni Montani; Fabrizio Pittorino

    2014-10-30

    We provide a cosmological implementation of the evolutionary quantum gravity, describing an isotropic Universe, in the presence of a negative cosmological constant and a massive (preinflationary) scalar field. We demonstrate that the considered Universe has a nonsingular quantum behavior, associated to a primordial bounce, whose ground state has a high occupation number. Furthermore, in such a vacuum state, the super-Hamiltonian eigenvalue is negative, corresponding to a positive emerging dust energy density. The regularization of the model is performed via a polymer quantum approach to the Universe scale factor and the proper classical limit is then recovered, in agreement with a preinflationary state of the Universe. Since the dust energy density is redshifted by the Universe deSitter phase and the cosmological constant does not enter the ground state eigenvalue, we get a late-time cosmology, compatible with the present observations, endowed with a turning point in the far future.

  7. Black Hole Thermodynamics in Modified Gravity

    E-Print Network [OSTI]

    Jonas R. Mureika; John W. Moffat; Mir Faizal

    2015-03-03

    We analyze the thermodynamics of a non-rotating and rotating black hole in a modified theory of gravity that includes scalar and vector modifications to general relativity, which results in a modified gravitational constant $G = G_N(1+\\alpha)$ and a new gravitational charge $Q = \\sqrt{\\alpha G_N}M$. The influence of the parameter $\\alpha$ alters the non-rotating black hole's lifetime, temperature and entropy profiles from the standard Schwarzschild case. The thermodynamics of a rotating black hole is analyzed and it is shown to possess stable, cold remnants. The thermodynamic properties of a vacuum solution regular at $r=0$ are investigated and the solution without a horizon called a "gray hole" is not expected to possess an information loss problem.

  8. What is Dynamics in Quantum Gravity?

    E-Print Network [OSTI]

    Malkiewicz, Przemyslaw

    2015-01-01

    Dynamics of general relativistic systems is given with respect to internal clocks. We investigate the extent to which the choice of internal clock in quantum description of the gravitational field determines the quantum dynamics. We develop our method by making use of the Hamilton-Jacobi theory, which is extended to include time coordinate transformations. Next, we apply our method to a quantum model of the flat Friedmann universe and compute some clock-induced deviations to semiclassical phase space portrait. Within a fixed quantization we find the abundance of possible semiclassical extensions to general relativity by switching between clocks. It follows that quantities like minimal volume, maximal curvature and even a number of quantum bounces, often used to describe quantum effects in gravity, are ill-defined.

  9. What is Dynamics in Quantum Gravity?

    E-Print Network [OSTI]

    Przemyslaw Malkiewicz

    2015-05-18

    Dynamics of general relativistic systems is given with respect to internal clocks. We investigate the extent to which the choice of internal clock in quantum description of the gravitational field determines the quantum dynamics. We develop our method by making use of the Hamilton-Jacobi theory, which is extended to include time coordinate transformations. Next, we apply our method to a quantum model of the flat Friedmann universe and compute some clock-induced deviations to semiclassical phase space portrait. Within a fixed quantization we find the abundance of possible semiclassical extensions to general relativity by switching between clocks. It follows that quantities like minimal volume, maximal curvature and even a number of quantum bounces, often used to describe quantum effects in gravity, are ill-defined.

  10. Phenomenologically viable Lorentz-violating quantum gravity

    E-Print Network [OSTI]

    Sotiriou, Thomas; Weinfurtner, Silke

    2009-01-01

    Horava's "Lifschitz point gravity" has many desirable features, but in its original incarnation one is forced to accept a non-zero cosmological constant of the wrong sign to be compatible with observation. We develop an extension of Horava's model that abandons "detailed balance", and in 3+1 dimensions exhibit all five marginal (renormalizable) and four relevant (super-renormalizable) operators, as determined by power counting. We also consider the classical limit of this theory, evaluate the Hamiltonian and super-momentum constraints, and extract the classical equations of motion in a form similar to the ADM formulation of general relativity. This puts the model in a framework amenable to developing detailed precision tests.

  11. Solar system tests of Ho?ava-Lifshitz gravity

    E-Print Network [OSTI]

    Tiberiu Harko; Zoltan Kovács; Francisco S. N. Lobo

    2010-10-28

    Recently, a renormalizable gravity theory with higher spatial derivatives in four dimensions was proposed by Ho\\v{r}ava. The theory reduces to Einstein gravity with a non-vanishing cosmological constant in IR, but it has improved UV behaviors. The spherically symmetric black hole solutions for an arbitrary cosmological constant, which represent the generalization of the standard Schwarzschild-(A)dS solution, has also been obtained for the Ho\\v{r}ava-Lifshitz theory. The exact asymptotically flat Schwarzschild type solution of the gravitational field equations in Ho\\v{r}ava gravity contains a quadratic increasing term, as well as the square root of a fourth order polynomial in the radial coordinate, and it depends on one arbitrary integration constant. The IR modified Ho\\v{r}ava gravity seems to be consistent with the current observational data, but in order to test its viability more observational constraints are necessary. In the present paper we consider the possibility of observationally testing Ho\\v{r}ava gravity at the scale of the Solar System, by considering the classical tests of general relativity (perihelion precession of the planet Mercury, deflection of light by the Sun and the radar echo delay) for the spherically symmetric black hole solution of Ho\\v{r}ava-Lifshitz gravity. All these gravitational effects can be fully explained in the framework of the vacuum solution of the gravity. Moreover, the study of the classical general relativistic tests also constrain the free parameter of the solution.

  12. Eikonal contributions to ultra high energy neutrino-nucleon cross sections in low scale gravity models

    E-Print Network [OSTI]

    E. M. Sessolo; D. W. McKay

    2008-11-18

    We calculate low scale gravity effects on the cross section for neutrino-nucleon scattering at center of mass energies up to the Greisen-Zatsepin-Kuzmin (GZK) scale, in the eikonal approximation. We compare the cases of an infinitely thin brane embedded in n=5 compactified extra-dimensions, and of a brane with a physical tension M_{S}=1 TeV and M_{S}=10 TeV. The extra dimensional Planck scale M_{D} is set at 10^{3} GeV and 2\\times10^{3} GeV. We also compare our calculations with neutral current standard model calculations in the same energy range, and compare the thin brane eikonal cross section to its saddle point approximation. New physics effects enhance the cross section by orders of magnitude on average. They are quite sensitive to M_{S} and M_{D} choices, though much less sensitive to n.

  13. Fluctuating Dimension in a Discrete Model for Quantum Gravity Based on the Spectral Action

    E-Print Network [OSTI]

    De Albuquerque, L C; Teotônio-Sobrinho, P; Albuquerque, Luiz C. de; Lyra, Jorge L. de; Teotonio-Sobrinho, Paulo

    2003-01-01

    The spectral action of Connes and Chamseddine is used as a starting point to define a discrete model for Euclidean quantum gravity. Instead of summing over ordinary geometries, we consider the sum over generalized geometries where topology, metric and dimension can fluctuate. The model describes the geometry of spaces with a countable number $n$ of points, and is related to the Gaussian unitary ensemble of Hermitian matrices. We show that this simple model has two phases. The expectation value $$, the average number of points in the universe, is finite in one phase and diverges in the other. We compute the critical point as well as the critical exponent of $$. Moreover, the space-time dimension $\\delta$ is a dynamical observable in our model, and plays the role of an order parameter. The computation of $$ is discussed and a lower bound is found, $ > 2$.

  14. PHYSICS OF FLUIDS 25, 086604 (2013) Gravity currents shoaling on a slope

    E-Print Network [OSTI]

    Sutherland, Bruce

    2013-01-01

    water rivers into the saline ocean form surface gravity currents. The study of gravity currents is also spills in the ocean.6 Gravity currents in a channel have been well studied through lockPHYSICS OF FLUIDS 25, 086604 (2013) Gravity currents shoaling on a slope Bruce R. Sutherland,1,2,a

  15. Gravity observations and 3D structure of the Earth , F. Chambat

    E-Print Network [OSTI]

    1 Gravity observations and 3D structure of the Earth Y. Ricard1 , F. Chambat Laboratoire des, Michigan-Ann Harbor University, USA. Short title: GRAVITY OBSERVATIONS AND 3D STRUCTURE OF THE EARTH 1. The determination of Earth's gravity field has benefited from various gravity missions that have been launched

  16. Gravity inversion using a binary formulation Richard A. Krahenbuhl* and Yaoguo Li

    E-Print Network [OSTI]

    Gravity inversion using a binary formulation Richard A. Krahenbuhl* and Yaoguo Li Gravity contrast that gives rise to zero gravity response on the surface. As a result, part of the salt structure structure using gravity data can be divided into two general categories. The first are interface inversions

  17. GRAVITY PERTURBED CRAPPER WAVES BENJAMIN F. AKERS, DAVID M. AMBROSE & J. DOUGLAS WRIGHT

    E-Print Network [OSTI]

    Wright, J. Douglas

    GRAVITY PERTURBED CRAPPER WAVES BENJAMIN F. AKERS, DAVID M. AMBROSE & J. DOUGLAS WRIGHT Abstract for but gravity is neglected. For certain parameter values, Crapper waves are known to have multi-valued height by the effect of gravity, yielding the existence of gravity-capillary waves nearby to the Crapper waves

  18. Emergent gravity/Non-linear U(1) gauge theory correspondence

    E-Print Network [OSTI]

    Supriya Kar; K. Priyabrat Pandey; Abhishek K. Singh; Sunita Singh

    2010-02-21

    Kaluza-Klein gravity is revisted, with renewed interest, in a type IIB string theory on $S^1\\times K3$. The irreducible curvature tensors are worked out in the, T-dual, emergent gravity in 4D to yield a non-linear U(1) gauge theory. Interestingly, the T-duality may be seen to describe an open/closed string duality at a self-dual string coupling. The obtained deformation in $AdS_5$ black hole is analyzed to introduce the notion of temperature in the emergent gravity underlying the recent idea of entropic force.

  19. Particles on a Circle in Canonical Lineal Gravity

    E-Print Network [OSTI]

    R. B. Mann

    2001-05-02

    A description of the canonical formulation of lineal gravity minimally coupled to N point particles in a circular topology is given. The Hamiltonian is found to be equal to the time-rate of change of the extrinsic curvature multiplied by the proper circumference of the circle. Exact solutions for pure gravity and for gravity coupled to a single particle are obtained. The presence of a single particle significantly modifies the spacetime evolution by either slowing down or reversing the cosmological expansion of the circle, depending upon the choice of parameters.

  20. Flat space (higher spin) gravity with chemical potentials

    E-Print Network [OSTI]

    Michael Gary; Daniel Grumiller; Max Riegler; Jan Rosseel

    2014-11-24

    We introduce flat space spin-3 gravity in the presence of chemical potentials and discuss some applications to flat space cosmology solutions, their entropy, free energy and flat space orbifold singularity resolution. Our results include flat space Einstein gravity with chemical potentials as special case. We discover novel types of phase transitions between flat space cosmologies with spin-3 hair and show that the branch that continuously connects to spin-2 gravity becomes thermodynamically unstable for sufficiently large temperature or spin-3 chemical potential.