Energy definition for quadratic curvature gravities
Ahmet Baykal
2012-12-03T23:59:59.000Z
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.
NGNP: High Temperature Gas-Cooled Reactor Key Definitions, Plant Capabilities, and Assumptions
Wayne Moe
2013-05-01T23:59:59.000Z
This document provides key definitions, plant capabilities, and inputs and assumptions related to the Next Generation Nuclear Plant to be used in ongoing efforts related to the licensing and deployment of a high temperature gas-cooled reactor. These definitions, capabilities, and assumptions were extracted from a number of NGNP Project sources such as licensing related white papers, previously issued requirement documents, and preapplication interactions with the Nuclear Regulatory Commission (NRC).
NGNP: High Temperature Gas-Cooled Reactor Key Definitions, Plant Capabilities, and Assumptions
Phillip Mills
2012-02-01T23:59:59.000Z
This document is intended to provide a Next Generation Nuclear Plant (NGNP) Project tool in which to collect and identify key definitions, plant capabilities, and inputs and assumptions to be used in ongoing efforts related to the licensing and deployment of a high temperature gas-cooled reactor (HTGR). These definitions, capabilities, and assumptions are extracted from a number of sources, including NGNP Project documents such as licensing related white papers [References 1-11] and previously issued requirement documents [References 13-15]. Also included is information agreed upon by the NGNP Regulatory Affairs group's Licensing Working Group and Configuration Council. The NGNP Project approach to licensing an HTGR plant via a combined license (COL) is defined within the referenced white papers and reference [12], and is not duplicated here.
Finzi, Adrien
, which for the first time defined the biochemical nature and source of the amyloid fibril in this form microscopic structure and x-ray diffraction pattern of amyloid fibrils in 1967, providing key insight of amyloidosis. Characterization of the protein deposits in dialysis-associated amyloidosis as 2- microglobulin
Communication Definitions... general definition
Jones, Ian L.
Communication Definitions... general definition "the process of conveying information from a sender to a receiver with the use of a medium in which the communicated information is understood the same way by both sender and receiver" (Wikipedia)! Biological communication Action by one organism (individual
Definition and Validation of the Key
Utrecht, Universiteit
of information and computing sciences, utrecht university technical report UU-CS-2005-041 www.cs.uu.nl #12 Sciences Utrecht University Utrecht, The Netherlands slinger.jansen@cs.uu.nl Sjaak Brinkkemper Institute for Information and Computing Sciences Utrecht University Utrecht, The Netherlands s.brinkkemper@cs.uu.nl ABSTRACT
Escher, Christine
) means the chemical compound containing one atom of carbon and two atoms of oxygen. (2) "Carbon dioxide) "Global Warming Potential factor" (GWP) means the radiative forcing impact of one mass-based unit. For instance, methane (CH4) has a GWP of 23, meaning that every gram of methane will trap 23 times as much
Moho topography beneath the Corinth Rift area (Greece) from inversion of gravity data
Demouchy, Sylvie
Moho topography beneath the Corinth Rift area (Greece) from inversion of gravity data C. Tiberi,1 to Miocene lithospheric instabilities. Key words: boudinage, continental rifts, gravity inversion, Greece
2010 Manufacturing Energy and Carbon Footprints: Definitions...
Broader source: Energy.gov (indexed) [DOE]
key terms and details assumptions and references used in the Manufacturing Energy and Carbon Footprints (2010 MECS) Definitions and Assumptions for the Manufacturing Energy and...
Weinberger, Hans
Definitions Calibration Parameter Dynamics Monte Carlo Simulation Concluding Remarks Using the SABR Model Jason Vinar Ameriprise Workshop 2012 Jason Vinar Using the SABR Model #12;Definitions Calibration which attempts to capture the volatility smile. This project will consist of Calibrating the SABR model
Key distributionKey distribution Key distribution, symmetric encryption
Fisher, Michael
COMP 522 Key distributionKey distribution COMP 522 Key distribution, symmetric encryption From in a secure way and must keep the key secure" · Important issue: how to distribute secret keys? COMP 522 Key distribution, manual delivery For two parties A and B: · A key could be created by A and delivered physically
Information systems definition architecture
Calapristi, A.J.
1996-06-20T23:59:59.000Z
The Tank Waste Remediation System (TWRS) Information Systems Definition architecture evaluated information Management (IM) processes in several key organizations. The intent of the study is to identify improvements in TWRS IM processes that will enable better support to the TWRS mission, and accommodate changes in TWRS business environment. The ultimate goals of the study are to reduce IM costs, Manage the configuration of TWRS IM elements, and improve IM-related process performance.
Kay, Bernard S
2015-01-01T23:59:59.000Z
We give an account of the matter-gravity entanglement hypothesis which, unlike the standard approach to entropy based on coarse-graining, offers a definition for the entropy of a closed system as a real and objective quantity. We explain how this new approach offers an explanation for the Second Law of Thermodynamics in general and a non-paradoxical understanding of information loss during black hole formation and evaporation in particular. We also very briefly review some recent related work on the nature of equilibrium states involving quantum black holes and point out how it promises to resolve some puzzling issues in the current version of the string theory approach to black hole entropy.
Is nonrelativistic gravity possible?
Kocharyan, A. A. [School of Mathematical Sciences, Monash University, Clayton 3800 (Australia)
2009-07-15T23:59:59.000Z
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.
B. L. Hu
1999-02-22T23:59:59.000Z
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.
Quantum Field Theory & Gravity
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Quantum Field Theory & Gravity Quantum Field Theory & Gravity Understanding discoveries at the Energy, Intensity, and Cosmic Frontiers Get Expertise Rajan Gupta (505) 667-7664...
Vocabulary of Definitions | EMSL
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
of Definitions Vocabulary of Definitions 800 Terms for Surface Chemical Analysis - ISO This information is provided through the cooperation of EMSL and the ASTM E42...
Quantum Public-Key Encryption with Information Theoretic Security
Jiangyou Pan; Li Yang
2012-02-20T23:59:59.000Z
We propose a definition for the information theoretic security of a quantum public-key encryption scheme, and present bit-oriented and two-bit-oriented encryption schemes satisfying our security definition via the introduction of a new public-key algorithm structure. We extend the scheme to a multi-bitoriented one, and conjecture that it is also information theoretically secure, depending directly on the structure of our new algorithm.
Gravity Control Propulsion: Towards a General Relativistic Approach
O. Bertolami; F. G. Pedro
2006-10-16T23:59:59.000Z
Evaluation of gravity control concepts should be examined with respect to currently known physical theories. In this work we study the hypothetical conversion of gravitational potential energy into kinetic energy using the formalism of general relativity. We show that the energy involved in the process greatly exceeds the Newtonian estimate, given the nature of general relativity. We conclude that the impact of any gravity manipulation for propulsion greatly depends fundamentally on its exact definition.
A simple argument for dark matter as an effect of slightly modified gravity
Peter K. F. Kuhfittig
2014-09-12T23:59:59.000Z
This note presents a simple argument showing that dark matter is an effect of $f(R)$ gravity based on the definition of slightly modified gravitational theories previously proposed by the author.
Chiral gravity, log gravity, and extremal CFT
Maloney, Alexander [Physics Department, McGill University, Montreal, QC H3A 2T8 (Canada); Song Wei [Key Laboratory of Frontiers in Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190 (China); Center for the Fundamental Laws of Nature Jefferson Physical Laboratory, Harvard University, Cambridge, Massachusetts 02138 (United States); Strominger, Andrew [Center for the Fundamental Laws of Nature Jefferson Physical Laboratory, Harvard University, Cambridge, Massachusetts 02138 (United States)
2010-03-15T23:59:59.000Z
We show that the linearization of all exact solutions of classical chiral gravity around the AdS{sub 3} vacuum have positive energy. Nonchiral 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 conformal field theories (CFT). Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We formally 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.
Public Key Cryptography and Key Management
Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]
2000-02-15T23:59:59.000Z
The use and management of certificate-based public key cryptography for the Department of Energy (DOE) requires the establishment of a public key infrastructure (PKI). This chapter defines the policy related to roles, requirements, and responsibilities for establishing and maintaining a DOE PKI and the documentation necessary to ensure that all certificates are managed in a manner that maintains the overall trust required to support a viable PKI. Canceled by DOE N 251.112.
The Web Services Vision Definition of Web Services
Cheverst, Keith
1 The Web Services Vision Overview Definition of Web Services Key concepts Difference from traditional web model Context Service-oriented architecture Distributed computing Overview Microsoft .NET vision Web Services Difference from traditional web model Context Service-oriented architecture
Broader source: Energy.gov [DOE]
Key Milestones/Outlook per the Department of Energy 2015 Congressional Budget Request, Environmental Management, March 2014
Olgyay, Victor W. (Victor Wayne)
1986-01-01T23:59:59.000Z
Home is an elusive concept. In one manner it is highly specific and individual in its definition, and in other aspects it is ubiquitous, present in our every act. In this thesis I explore several possible definitions of ...
Einstein Gravity, Massive Gravity, Multi-Gravity and Nonlinear Realizations
Garrett Goon; Kurt Hinterbichler; Austin Joyce; Mark Trodden
2014-12-18T23:59:59.000Z
The existence of a ghost free theory of massive gravity begs for an interpretation as a Higgs phase of General Relativity. We revisit the study of massive gravity as a Higgs phase. Absent a compelling microphysical model of spontaneous symmetry breaking in gravity, we approach this problem from the viewpoint of nonlinear realizations. We employ the coset construction to search for the most restrictive symmetry breaking pattern whose low energy theory will both admit the de Rham--Gabadadze--Tolley (dRGT) potentials and nonlinearly realize every symmetry of General Relativity, thereby providing a new perspective from which to build theories of massive gravity. In addition to the known ghost-free terms, we find a novel parity violating interaction which preserves the constraint structure of the theory, but which vanishes on the normal branch of the theory. Finally, the procedure is extended to the cases of bi-gravity and multi-vielbein theories. Analogous parity violating interactions exist here, too, and may be non-trivial for certain classes of multi-metric theories.
Quantum dense key distribution
Degiovanni, I.P.; Ruo Berchera, I.; Castelletto, S.; Rastello, M.L.; Bovino, F.A.; Colla, A.M.; Castagnoli, G. [Istituto Elettrotecnico Nazionale G. Ferraris, Strada delle Cacce 91, 10135 Torino (Italy); ELSAG SpA, Via Puccini 2, 16154, Genova (Italy)
2004-03-01T23:59:59.000Z
This paper proposes a protocol for quantum dense key distribution. This protocol embeds the benefits of a quantum dense coding and a quantum key distribution and is able to generate shared secret keys four times more efficiently than the Bennet-Brassard 1984 protocol. We hereinafter prove the security of this scheme against individual eavesdropping attacks, and we present preliminary experimental results, showing its feasibility.
Broader source: Energy.gov [DOE]
This document lists key events beginning with the April 20 fire on the Deepwater Horizon through July 28th. Updated July 28, 2010.
Carrington, Emily
will be accessing. For Johnson Hall exterior door access bring a copy of this form to the Earth & Space SciencesKey Request Form Name: (Last) (First) Contact Info Keys Cardswipe UW Email: Hitchcock Exterior Door Room:_________ Room:_________ Johnson Room:_________ Room:_________ Kincaid Exterior Door Room
Hagans, Karla G. (Livermore, CA); Clough, Robert E. (Danville, CA)
2000-01-01T23:59:59.000Z
An optical key system comprises a battery-operated optical key and an isolated lock that derives both its operating power and unlock signals from the correct optical key. A light emitting diode or laser diode is included within the optical key and is connected to transmit a bit-serial password. The key user physically enters either the code-to-transmit directly, or an index to a pseudorandom number code, in the key. Such person identification numbers can be retained permanently, or ephemeral. When a send button is pressed, the key transmits a beam of light modulated with the password information. The modulated beam of light is received by a corresponding optical lock with a photovoltaic cell that produces enough power from the beam of light to operate a password-screen digital logic. In one application, an acceptable password allows a two watt power laser diode to pump ignition and timing information over a fiberoptic cable into a sealed engine compartment. The receipt of a good password allows the fuel pump, spark, and starter systems to each operate. Therefore, bypassing the lock mechanism as is now routine with automobile thieves is pointless because the engine is so thoroughly disabled.
Particle Dynamics And Emergent Gravity
Amir H. Fatollahi
2008-05-08T23:59:59.000Z
The emergent gravity proposal is examined within the framework of noncommutative QED/gravity correspondence from particle dynamics point of view.
3D gravity with dust: classical and quantum theory
Viqar Husain; Jonathan Ziprick
2015-06-02T23:59:59.000Z
We study the Einstein gravity and dust system in three spacetime dimensions as an example of a non-perturbative quantum gravity model with local degrees of freedom. We derive the Hamiltonian theory in the dust time gauge and show that it has a rich class of exact solutions. These include the Ba\\~nados-Teitelboim-Zanelli black hole, static solutions with naked singularities and travelling wave solutions with dynamical horizons. We give a complete quantization of the wave sector of the theory, including a definition of a self-adjoint spacetime metric operator. This operator is used to demonstrate the quantization of deficit angle and the fluctuation of dynamical horizons.
Combinatorial Design of Key Distribution Mechanisms for Wireless Sensor Networks
Bystroff, Chris
Combinatorial Design of Key Distribution Mechanisms for Wireless Sensor Networks Seyit A. CÂ¸amtepe1 of the most challenging security issues in wireless sensor networks where sensor nodes are randomly scattered-chain sizes. 1 Introduction and Problem Definition In this work, we consider a sensor network in which sensor
Combinatorial Design of Key Distribution Mechanisms for Wireless Sensor Networks
Bystroff, Chris
Combinatorial Design of Key Distribution Mechanisms for Wireless Sensor Networks Seyit A. Câ?º amtepe of the most challenging security issues in wireless sensor networks where sensor nodes are randomly scatteredÂchain sizes. 1 Introduction and Problem Definition In this work, we consider a sensor network in which sensor
Dec 7, 2013 ... As soon as the brakes of a railroad car in West Lafayette are released, the car will roll down under the force of gravity. It will accelerate, then ...
Crkvenjakov, R.; Drmanac, R.
1991-07-01T23:59:59.000Z
The subject of this paper is the definition of species based on the assumption that genome is the fundamental level for the origin and maintenance of biological diversity. For this view to be logically consistent it is necessary to assume the existence and operation of the new law which we call genome law. For this reason the genome law is included in the explanation of species phenomenon presented here even if its precise formulation and elaboration are left for the future. The intellectual underpinnings of this definition can be traced to Goldschmidt. We wish to explore some philosophical aspects of the definition of species in terms of the genome. The point of proposing the definition on these grounds is that any real advance in evolutionary theory has to be correct in both its philosophy and its science.
Cryptographic Key Management System
No, author
2014-02-21T23:59:59.000Z
This report summarizes the outcome of U.S. Department of Energy (DOE) contract DE-OE0000543, requesting the design of a Cryptographic Key Management System (CKMS) for the secure management of cryptographic keys for the energy sector infrastructure. Prime contractor Sypris Electronics, in collaboration with Oak Ridge National Laboratories (ORNL), Electric Power Research Institute (EPRI), Valicore Technologies, and Purdue University's Center for Education and Research in Information Assurance and Security (CERIAS) and Smart Meter Integration Laboratory (SMIL), has designed, developed and evaluated the CKMS solution. We provide an overview of the project in Section 3, review the core contributions of all contractors in Section 4, and discuss bene#12;ts to the DOE in Section 5. In Section 6 we describe the technical construction of the CKMS solution, and review its key contributions in Section 6.9. Section 7 describes the evaluation and demonstration of the CKMS solution in different environments. We summarize the key project objectives in Section 8, list publications resulting from the project in Section 9, and conclude with a discussion on commercialization in Section 10 and future work in Section 11.
Demand Response in the U.S.- Key trends and federal facility participation
Broader source: Energy.gov [DOE]
Presentation—given at the Federal Utility Partnership Working Group (FUPWG) Fall 2008 meeting—provides demand response (DR) definition, current status of DR in the United States, key DR trends, and federal participation issues.
Stiffness modeling of robotic manipulator with gravity compensator
Paris-Sud XI, UniversitÃ© de
to the stiffness modeling of a heavy industrial robot of the Kuka family. Key words: Stiffness modeling, gravity compensator, industrial robot. 1 Introduction Recently, in aerospace industry much attention is paid these requirements, industrial robots are more and more used to replace conventional CNC-machines, which are limited
Thermo-electric transport in gauge/gravity models with momentum dissipation
Andrea Amoretti; Alessandro Braggio; Nicola Maggiore; Nicodemo Magnoli; Daniele Musso
2014-10-07T23:59:59.000Z
We present a systematic definition and analysis of the thermo-electric linear response in gauge/gravity systems focusing especially on models with massive gravity in the bulk and therefore momentum dissipation in the dual field theory. A precise treatment of finite counter-terms proves to be essential to yield a consistent physical picture whose hydrodynamic and beyond-hydrodynamics behaviors noticeably match with field theoretical expectations. The model furnishes a possible gauge/gravity description of the crossover from the quantum-critical to the disorder-dominated Fermi-liquid behaviors, as expected in graphene.
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The FutureCommentsEnergyand SustainedBio-OilBioenergy 2015 AgendaBioenergyKEY
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |IsLoveReferenceAgenda Workshop AgendaGraphic of aEnergy SystemsKey
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated CodesTransparency VisitSilver Toyota PriusNSR Key Number Retrieval Pease
Time Gravity and Quantum Mechanics
W. G. Unruh
1993-12-17T23:59:59.000Z
Time plays different roles in quantum mechanics and gravity. These roles are examined and the problems that the conflict in the roles presents for quantum gravity are briefly summarised.
Nemoto, S.
1989-03-07T23:59:59.000Z
A key-shift transmission is described, characterized by the speed-change shaft being divided into a pair of trough-shaped shaft halves each having an arched inner surface which defines a part of a cylindrical bore extending axially through the speed-change shaft thereby the shaft being formed into a hollow shaft, and by each of the shaft halves including a pair of flattened end surfaces which extend axially of each shaft half at both sides of the inner surface, one of the end surfaces having thereon an axially elongated projection and the other of the end surfaces having herein an axially elongated recess of a depth smaller than the height of the projection. The pair of shaft halves are engaged to each other co-rotatably by fitting the projections of the respective shaft halves into the recesses of the respective shaft halves so as to form in an outer surface of the speed-change shaft a pair of elongated axial grooves which are located radially outwardly of the elongated projections of the respective shaft halves and between the flattened end surfaces of the respective shaft halves. A pair of the shift keys are disposed within the pair of elongated axial grooves.
Key recycling in authentication
Christopher Portmann
2014-09-29T23:59:59.000Z
In their seminal work on authentication, Wegman and Carter propose that to authenticate multiple messages, it is sufficient to reuse the same hash function as long as each tag is encrypted with a one-time pad. They argue that because the one-time pad is perfectly hiding, the hash function used remains completely unknown to the adversary. Since their proof is not composable, we revisit it using a composable security framework. It turns out that the above argument is insufficient: if the adversary learns whether a corrupted message was accepted or rejected, information about the hash function is leaked, and after a bounded finite amount of rounds it is completely known. We show however that this leak is very small: Wegman and Carter's protocol is still $\\epsilon$-secure, if $\\epsilon$-almost strongly universal$_2$ hash functions are used. This implies that the secret key corresponding to the choice of hash function can be reused in the next round of authentication without any additional error than this $\\epsilon$. We also show that if the players have a mild form of synchronization, namely that the receiver knows when a message should be received, the key can be recycled for any arbitrary task, not only new rounds of authentication.
Sheridan, Jennifer
Major; People's Institute for Survival and Beyond, New Orleans 2. Power is the ability to define reality and to convince other people that it is their definition. ~ Dr. Wade Nobles 3. Power is the capacity to act. 4 different cultures. [JL] RACISM Racism is race prejudice plus power [See Racist]. People's Institute calls
3 Library Regulations Definitions
Mottram, Nigel
3 Library Regulations Definitions In Regulation 3: 'Library' means the University Library as defined in Regulation 3.1; 'Library staff' means the staff of the University Library; 'Librarian' means the University Librarian and Head of Information Resources Directorate or nominee; `Library Committee' means
Behmer, Spencer T.
Definitions Â· Numbered Space Â a single space marked with a number and reserved for a single permit 24/7 Â· Unnumbered Space Â a space which can be used by any customer allowed to park in that lot. High Low Average Question 4: If I buy a staff permit for an UNNUMBERED* space in a non-gated surface
Team Building Toolkit KEYS -Keys to Enhance Your Supervisory Success
Walker, Matthew P.
Team Building Toolkit KEYS - Keys to Enhance Your Supervisory Success University of California to Enhance Your Supervisory Success 2 | P a g e Table of Contents Stages of Team Development ................................................................................................ 4 Team Building at a Glance
Table Definitions, Sources, and Explanatory Notes
Gasoline and Diesel Fuel Update (EIA)
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Table Definitions, Sources, and Explanatory Notes
Gasoline and Diesel Fuel Update (EIA)
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Table Definitions, Sources, and Explanatory Notes
Gasoline and Diesel Fuel Update (EIA)
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Table Definitions, Sources, and Explanatory Notes
Gasoline and Diesel Fuel Update (EIA)
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Table Definitions, Sources, and Explanatory Notes
Gasoline and Diesel Fuel Update (EIA)
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Table Definitions, Sources, and Explanatory Notes
Gasoline and Diesel Fuel Update (EIA)
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Table Definitions, Sources, and Explanatory Notes
Gasoline and Diesel Fuel Update (EIA)
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Table Definitions, Sources, and Explanatory Notes
Gasoline and Diesel Fuel Update (EIA)
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Table Definitions, Sources, and Explanatory Notes
Gasoline and Diesel Fuel Update (EIA)
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Table Definitions, Sources, and Explanatory Notes
Gasoline and Diesel Fuel Update (EIA)
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Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. CoalInputsTotal Stocks Definitions KeyPrices,
Husson, Laurent
Cenozoic gravity tectonics in the northern Gulf of Mexico induced by crustal extension. A new HUSSON3 Key-words. Gravity tectonics, Cenozoic rifting, Gulf of Mexico, Texas, Northeast Mexico. Abstract. The Gulf of Mexico margin in Texas is one of the most impressive examples of starved passive
Definitions and motivation More theory
Duval, Art
Definitions and motivation Examples More theory The Importance of being Equivalent: The Ubiquity of being Equivalent: #12;Definitions and motivation Examples More theory Fractions Geometry Real life Equivalent: #12;Definitions and motivation Examples More theory Fractions Geometry Real life Summary Equality
Motivation and definitions Dimension theory
Climenhaga, Vaughn
Motivation and definitions Dimension theory Results: old and new Multifractal analysis of Birkhoff averages #12;Motivation and definitions Dimension theory Results: old and new Outline 1 Motivation and definitions A multifractal decomposition Example 2 Dimension theory Quantifying level sets A dynamically
Definitions and motivation More theory
Duval, Art
Definitions and motivation Examples More theory Equivalence relations in mathematics, K-16+ Art;Definitions and motivation Examples More theory Fractions Geometry Real life One reason fractions are hard 2 3 Duval Equivalence relations in mathematics, K-16+ #12;Definitions and motivation Examples More theory
Bending of light in conformal Weyl gravity
Sultana, Joseph; Kazanas, Demosthenes [Astrophysics Science Division, NASA/Goddard Space Flight Center, Greenbelt, Maryland 20771 (United States) and Department of Mathematics, University of Malta, Msida (Malta); Astrophysics Science Division, NASA/Goddard Space Flight Center, Greenbelt, Maryland 20771 (United States)
2010-06-15T23:59:59.000Z
We reexamine the bending of light issue associated with the metric of the static, spherically symmetric solution of Weyl gravity discovered by Mannheim and Kazanas (1989). To this end we employ the procedure used recently by Rindler and Ishak to obtain the bending angle of light by a centrally concentrated spherically symmetric matter distribution in a Schwarzschild-de Sitter background. In earlier studies the term {gamma}r in the metric led to the paradoxical result of a bending angle proportional to the photon impact parameter, when using the usual formalism appropriate to asymptotically flat space-times. However, employing the approach of light bending of Rindler and Ishak we show that the effects of this term are in fact insignificant, with the discrepancy between the two procedures attributed to the definition of the bending angle between the asymptotically flat and nonflat spaces.
Gravity on Conformal Superspace
Bryan Kelleher
2003-11-11T23:59:59.000Z
The configuration space of general relativity is superspace - the space of all Riemannian 3-metrics modulo diffeomorphisms. However, it has been argued that the configuration space for gravity should be conformal superspace - the space of all Riemannian 3-metrics modulo diffeomorphisms and conformal transformations. Taking this conformal nature seriously leads to a new theory of gravity which although very similar to general relativity has some very different features particularly in cosmology and quantisation. It should reproduce the standard tests of general relativity. The cosmology is studied in some detail. The theory is incredibly restrictive and as a result admits an extremely limited number of possible solutions. The problems of the standard cosmology are addressed and most remarkably the cosmological constant problem is resolved in a natural way. The theory also has several attractive features with regard to quantisation particularly regarding the problem of time.
Gravity, Dimension, Equilibrium, & Thermodynamics
Jerome Perez
2006-03-30T23:59:59.000Z
Is it actually possible to interpret gravitation as space's property in a pure classical way. Then, we note that extended self-gravitating system equilibrium depends directly on the number of dimension of the space in which it evolves. Given those precisions, we review the principal thermodynamical knowledge in the context of classical gravity with arbitrary dimension of space. Stability analyses for bounded 3D systems, namely the Antonov instability paradigm, are then rapproched to some amazing properties of globular clusters and galaxies.
Iver Brevik
2012-11-23T23:59:59.000Z
A bulk viscosity is introduced in the formalism of modified gravity. It is shown that, on the basis of a natural scaling law for the viscosity, a simple solution can be found for quantities such as the Hubble parameter and the energy density. These solutions may incorporate a viscosity-induced Big Rip singularity. By introducing a phase transition in the cosmic fluid, the future singularity can nevertheless in principle be avoided.
Lie algebraic noncommutative gravity
Banerjee, Rabin; Samanta, Saurav [S. N. Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake, Kolkata-700098 (India); Mukherjee, Pradip [Presidency College, 86/1 College Street, Kolkata-700073, West-Bengal (India)
2007-06-15T23:59:59.000Z
We exploit the Seiberg-Witten map technique to formulate the theory of gravity defined on a Lie algebraic noncommutative space-time. Detailed expressions of the Seiberg-Witten maps for the gauge parameters, gauge potentials, and the field strengths have been worked out. Our results demonstrate that notwithstanding the introduction of more general noncommutative structure there is no first order correction, exactly as happens for a canonical (i.e. constant) noncommutativity.
Soot Nanostructure: Definition, Quantification, and Implications...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Soot Nanostructure: Definition, Quantification, and Implications Soot Nanostructure: Definition, Quantification, and Implications 2004 Diesel Engine Emissions Reduction (DEER)...
Koyama, Kazuya
2015-01-01T23:59:59.000Z
Einstein's theory of General Relativity (GR) is tested accurately within the local universe i.e., the Solar System, but this leaves open the possibility that it is not a good description at the largest scales in the Universe. The standard model of cosmology assumes GR as the theory to describe gravity on all scales. In 1998, astronomers made the surprising discovery that the expansion of the Universe is accelerating, not slowing down. This late-time acceleration of the Universe has become the most challenging problem in theoretical physics. Within the framework of GR, the acceleration would originate from an unknown dark energy. Alternatively, it could be that there is no dark energy and GR itself is in error on cosmological scales. The standard model of cosmology is based on a huge extrapolation of our limited knowledge of gravity. This discovery of the late time acceleration of the Universe may require us to revise the theory of gravity and the standard model of cosmology based on GR. We will review recent ...
Mass and Weak Field Limit of Boson Stars in Brans Dicke Gravity
A. W. Whinnett
1999-06-14T23:59:59.000Z
We study boson stars in Brans Dicke gravity and use them to illustrate some of the properties of three different mass definitions: the Schwarzschild mass, the Keplerian mass and the Tensor mass. We analyse the weak field limit of the solutions and show that only the Tensor mass leads to a physically reasonable definition of the binding energy. We examine numerically strong field $\\omega=-1$ solutions and show how, in this extreme case, the three mass values and the conserved particle number behave as a function of the central boson field amplitude. The numerical studies imply that for $\\omega=-1$, solutions with extremal Tensor mass also have extremal particle number. This is a property that a physically reasonable definition of the mass of a boson star must have, and we prove analytically that this is true for all values of $\\omega$. The analysis supports the conjecture that the Tensor mass uniquely describes the total energy of an asymptotically flat solution in BD gravity.
Entropic Gravity in Rindler Space
Edi Halyo
2011-04-13T23:59:59.000Z
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.
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AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch > The EnergyCenterDioxideDocumentationThreeNewsfuelNotes and Definitions
Lifshitz Gravity for Lifshitz Holography
Tom Griffin; Petr Horava; Charles M. Melby-Thompson
2012-11-20T23:59:59.000Z
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.
Diversity & Flexibility Key to Sustainability
Broader source: Energy.gov [DOE]
Plenary V: Biofuels and Sustainability: Acknowledging Challenges and Confronting MisconceptionsDiversity & Flexibility Key to SustainabilityDavid Babson, Senior Fuels Engineer, Union of...
Proof and Definition in Logic and Type Theory Proof and Definition in Logic and Type Theory
Adams, Robin
Proof and Definition in Logic and Type Theory Proof and Definition in Logic and Type Theory Robin questions. #12;Proof and Definition in Logic and Type Theory Definition and Proof Definition and proof -- but they are not in predicate logic or type theory. #12;Proof and Definition in Logic and Type Theory Methods of Definition
Generalized quantum gravity condensates for homogeneous geometries and cosmology
Daniele Oriti; Daniele Pranzetti; James P. Ryan; Lorenzo Sindoni
2015-01-05T23:59:59.000Z
We construct a generalized class of quantum gravity condensate states, that allows the description of continuum homogeneous quantum geometries within the full theory. They are based on similar ideas already applied to extract effective cosmological dynamics from the group field theory formalism, and thus also from loop quantum gravity. However, they represent an improvement over the simplest condensates used in the literature, in that they are defined by an infinite superposition of graph-based states encoding in a precise way the topology of the spatial manifold. The construction is based on the definition of refinement operators on spin network states, written in a second quantized language. The construction lends itself easily to be applied also to the case of spherically symmetric quantum geometries.
Ivan Dimitrijevic; Branko Dragovich; Jelena Grujic; Zoran Rakic
2012-04-09T23:59:59.000Z
We consider some aspects of nonlocal modified gravity, where nonlocality is of the type $R \\mathcal{F}(\\Box) R$. In particular, using ansatz of the form $\\Box R = c R^\\gamma,$ we find a few $R(t)$ solutions for the spatially flat FLRW metric. There are singular and nonsingular bounce solutions. For late cosmic time, scalar curvature R(t) is in low regime and scale factor a(t) is decelerated. R (t) = 0 satisfies all equations when k = -1.
Ning Wu
2005-10-01T23:59:59.000Z
It is well-known that energy-momentum is the source of gravitational field. For a long time, it is generally believed that only stars with huge masses can generate strong gravitational field. Based on the unified theory of gravitational interactions and electromagnetic interactions, a new mechanism of the generation of gravitational field is studied. According to this mechanism, in some special conditions, electromagnetic energy can be directly converted into gravitational energy, and strong gravitational field can be generated without massive stars. Gravity impulse found in experiments is generated by this mechanism.
Bergshoeff, Eric A.; Rosseel, Jan [Centre for Theoretical Physics, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands); Hohm, Olaf [Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Townsend, Paul K. [Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)
2011-05-15T23:59:59.000Z
The physical modes of a recently proposed D-dimensional 'critical gravity', linearized about its anti-de Sitter vacuum, are investigated. All 'log mode' solutions, which we categorize as 'spin-2' or 'Proca', arise as limits of the massive spin-2 modes of the noncritical theory. The linearized Einstein tensor of a spin-2 log mode is itself a 'nongauge' solution of the linearized Einstein equations whereas the linearized Einstein tensor of a Proca mode takes the form of a linearized general coordinate transformation. Our results suggest the existence of a holographically dual logarithmic conformal field theory.
Reduced models for quantum gravity
T. Thiemann
1999-10-04T23:59:59.000Z
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.
Canonical Analysis of Unimodular Gravity
J. Kluson
2014-10-07T23:59:59.000Z
This short note is devoted to the Hamiltonian analysis of the Unimodular Gravity.We treat the unimodular gravity as General Relativity action with the unimodular constraint imposed with the help of Lagrange multiplier. We perform the canonical analysis of the resulting theory and determine its constraint structure.
Energy Contents of Gravitational Waves in Teleparallel Gravity
M. Sharif; Sumaira Taj
2009-10-02T23:59:59.000Z
The conserved quantities, that are, gravitational energy-momentum and its relevant quantities are investigated for cylindrical and spherical gravitational waves in the framework of teleparallel equivalent of General Relativity using the Hamiltonian approach. For both cylindrical and spherical gravitational waves, we obtain definite energy and constant momentum. The constant momentum shows consistency with the results available in General Relativity and teleparallel gravity. The angular momentum for cylindrical and spherical gravitational waves also turn out to be constant. Further, we evaluate their gravitational energy-momentum fluxes and gravitational pressure.
Tomography increases key rates of quantum-key-distribution protocols
Shun Watanabe; Ryutaroh Matsumoto; Tomohiko Uyematsu
2008-07-22T23:59:59.000Z
We construct a practically implementable classical processing for the BB84 protocol and the six-state protocol that fully utilizes the accurate channel estimation method, which is also known as the quantum tomography. Our proposed processing yields at least as high key rate as the standard processing by Shor and Preskill. We show two examples of quantum channels over which the key rate of our proposed processing is strictly higher than the standard processing. In the second example, the BB84 protocol with our proposed processing yields a positive key rate even though the so-called error rate is higher than the 25% limit.
Quantum key distribution with key extracted from basis information
Xiongfeng Ma
2014-10-20T23:59:59.000Z
In conventional quantum key distribution protocols, the secure key is normally extracted from the measurement outcomes of the system. Here, a different approach is proposed, where the secure key is extracted from the measurement bases, rather than outcomes. Compared to the original Bennett-Brassard-1984 protocol, the proposed protocol involves no hardware change but modifications in data postprocessing. We show that this protocol is more robust against detector efficiency attacks and photon-number-splitting attacks when practical detectors and photon sources are used.
Finite key analysis for symmetric attacks in quantum key distribution
Meyer, Tim; Kampermann, Hermann; Kleinmann, Matthias; Bruss, Dagmar [Institut fuer Theoretische Physik III, Heinrich-Heine-Universitaet Duesseldorf, D-40225 Duesseldorf (Germany)
2006-10-15T23:59:59.000Z
We introduce a constructive method to calculate the achievable secret key rate for a generic class of quantum key distribution protocols, when only a finite number n of signals is given. Our approach is applicable to all scenarios in which the quantum state shared by Alice and Bob is known. In particular, we consider the six state protocol with symmetric eavesdropping attacks, and show that for a small number of signals, i.e., below n{approx}10{sup 4}, the finite key rate differs significantly from the asymptotic value for n{yields}{infinity}. However, for larger n, a good approximation of the asymptotic value is found. We also study secret key rates for protocols using higher-dimensional quantum systems.
Social Media Ad Metrics Definitions
Collins, Gary S.
these metrics to encourage growth through consistency. Social media speaks to a new way of understanding howSocial Media Ad Metrics Definitions Released May 2009 #12;Social Media Metrics Definitions © 2008 & Social Media Committee. About the IAB's User-Generated Content & Social Media Committee: The User
GRAPH THEORY STUDY GUIDE 1. Definitions
Cooper, Joshua N.
GRAPH THEORY STUDY GUIDE 1. Definitions Definition 1 (Partition of A). A set A = A1, ..., Ak. Definition 2 (Vertex set). The set of vertices in a graph denoted by V (G). Definition 3 (Edge set). The set of edges in a graph denoted by E(G). Definition 4 (Order). the number of vertices of a graph G written |G
AdS Chern-Simons Gravity induces Conformal Gravity
Rodrigo Aros; Danilo E. Diaz
2013-12-25T23:59:59.000Z
The leitmotif of this paper is the question of whether four- and higher even-dimensional Conformal Gravities do have a Chern-Simons pedigree. We show that Weyl gravity can be obtained as dimensional reduction of a five-dimensional Chern-Simons action for a suitable (gauged-fixed, tractor-like) five-dimensional AdS connection. The gauge-fixing and dimensional reduction program admits a readily generalization to higher dimensions for the case of certain conformal gravities obtained by contractions of the Weyl tensor.
M. G. Romania; N. C. Tsamis; R. P. Woodard
2014-12-05T23:59:59.000Z
We review some perturbative results obtained in quantum gravity in an accelerating cosmological background. We then describe a class of non-local, purely gravitational models which have the correct structure to reproduce the leading infrared logarithms of quantum gravitational back-reaction during the inflationary regime. These models end inflation in a distinctive phase of oscillations with slight and short violations of the weak energy condition and should, when coupled to matter, lead to rapid reheating. By elaborating this class of models we exhibit one that has the same behaviour during inflation, goes quiescent until the onset of matter domination, and induces a small, positive cosmological constant of about the right size thereafter. We also briefly comment on the primordial density perturbations that this class of models predict.
Henneaux, Marc; Teitelboim, Claudio [Physique Theorique et Mathematique and International Solvay Institutes, Universite Libre de Bruxelles, Campus Plaine C. P. 231, B-1050 Brussels (Belgium) and Centro de Estudios Cientificos (CECS), Valdivia (Chile); Centro de Estudios Cientificos (CECS), Valdivia (Chile)
2005-01-15T23:59:59.000Z
We show that duality transformations of linearized gravity in four dimensions, i.e., rotations of the linearized Riemann tensor and its dual into each other, can be extended to the dynamical fields of the theory so as to be symmetries of the action and not just symmetries of the equations of motion. Our approach relies on the introduction of two superpotentials, one for the spatial components of the spin-2 field and the other for their canonically conjugate momenta. These superpotentials are two-index, symmetric tensors. They can be taken to be the basic dynamical fields and appear locally in the action. They are simply rotated into each other under duality. In terms of the superpotentials, the canonical generator of duality rotations is found to have a Chern-Simons-like structure, as in the Maxwell case.
Natural Inflation and Quantum Gravity
Anton de la Fuente; Prashant Saraswat; Raman Sundrum
2015-01-29T23:59:59.000Z
Cosmic Inflation provides an attractive framework for understanding the early universe and the cosmic microwave background. It can readily involve energies close to the scale at which Quantum Gravity effects become important. General considerations of black hole quantum mechanics suggest nontrivial constraints on any effective field theory model of inflation that emerges as a low-energy limit of quantum gravity, in particular the constraint of the Weak Gravity Conjecture. We show that higher-dimensional gauge and gravitational dynamics can elegantly satisfy these constraints and lead to a viable, theoretically-controlled and predictive class of Natural Inflation models.
Riding Gravity Away from Doomsday
Sen, Ashoke
2015-01-01T23:59:59.000Z
The discovery that most of the energy density in the universe is stored in the form of dark energy has profound consequences for our future. In particular our current limited understanding of quantum theory of gravity indicates that some time in the future our universe will undergo a phase transition that will destroy us and everything else around us instantaneously. However the laws of gravity also suggest a way out -- some of our descendants could survive this catastrophe by riding gravity away from the danger. In this essay I describe the tale of this escape from doomsday.
Riding Gravity Away from Doomsday
Ashoke Sen
2015-03-27T23:59:59.000Z
The discovery that most of the energy density in the universe is stored in the form of dark energy has profound consequences for our future. In particular our current limited understanding of quantum theory of gravity indicates that some time in the future our universe will undergo a phase transition that will destroy us and everything else around us instantaneously. However the laws of gravity also suggest a way out -- some of our descendants could survive this catastrophe by riding gravity away from the danger. In this essay I describe the tale of this escape from doomsday.
Critical Gravity in Four Dimensions
Lue, H. [China Economics and Management Academy, Central University of Finance and Economics, Beijing 100081 (China); Institute for Advanced Study, Shenzhen University, Nanhai Avenue 3688, Shenzhen 518060 (China); Pope, C. N. [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, College Station, Texas 77843 (United States); DAMTP, Centre for Mathematical Sciences, Cambridge University, Wilberforce Road, Cambridge CB3 OWA (United Kingdom)
2011-05-06T23:59:59.000Z
We study four-dimensional gravity theories that are rendered renormalizable by the inclusion of curvature-squared terms to the usual Einstein action with a cosmological constant. By choosing the parameters appropriately, the massive scalar mode can be eliminated and the massive spin-2 mode can become massless. This ''critical'' theory may be viewed as a four-dimensional analogue of chiral topologically massive gravity, or of critical 'new massive gravity' with a cosmological constant, in three dimensions. We find that the on-shell energy for the remaining massless gravitons vanishes. There are also logarithmic spin-2 modes, which have positive energy. The mass and entropy of standard Schwarzschild-type black holes vanish. The critical theory might provide a consistent toy model for quantum gravity in four dimensions.
Quantum Gravity: Motivations and Alternatives
Reiner Hedrich
2009-08-03T23:59:59.000Z
The mutual conceptual incompatibility between GR and QM/QFT is generally seen as the most essential motivation for the development of a theory of Quantum Gravity (QG). It leads to the insight that, if gravity is a fundamental interaction and QM is universally valid, the gravitational field will have to be quantized, not at least because of the inconsistency of semi-classical theories of gravity. If this means to quantize GR, its identification of the gravitational field with the spacetime metric has to be taken into account. And the resulting quantum theory has to be background-independent. This can not be achieved by means of quantum field theoretical procedures. More sophisticated strategies have to be applied. One of the basic requirements for such a quantization strategy is that the resulting quantum theory has GR as a classical limit. - However, should gravity not be a fundamental, but an residual, emergent interaction, it could very well be an intrinsically classical phenomenon. Should QM be nonetheless universally valid, we had to assume a quantum substrate from which gravity would result as an emergent classical phenomenon. And there would be no conflict with the arguments against semi-classical theories, because there would be no gravity at all on the substrate level. The gravitational field would not have any quantum properties, and a quantization of GR would not lead to any fundamental theory. The objective of a theory of 'QG' would instead be the identification of the quantum substrate from which gravity results. - The paper tries to give an overview over the main options for theory construction in the field of QG. Because of the still unclear status of gravity and spacetime, it pleads for the necessity of a plurality of conceptually different approaches to QG.
Review of sour service definitions
McIntyre, D.R.; Boah, J.K. [Saudi Aramco, Dhahran (Saudi Arabia)
1996-08-01T23:59:59.000Z
Case histories and laboratory test data are presented to compare the predictive utility of NACE MR0175 with three alternatives. With some exceptions, the MR0175 definition is useful and conservative for most cases. The definition based on water phase pH and hydrogen sulfide (H{sub 2}S) partial pressure, proposed in European Federation of Corrosion (EFC) pub. 16, is not recommended since it does not predict sulfide stress cracking (SSC) in refining environments and presents higher risk of SSC of sweet service materials in certain Arabian Gulf production environments. A modified definition of sour service is proposed, which uses the MR0175 definition except in cases of very low water phase pH. 47 refs., 4 figs., 1 tab.
Crop Insurance Terms and Definitions
Stokes, Kenneth; Waller, Mark L.; Outlaw, Joe; Barnaby, G. A. Art
2008-10-17T23:59:59.000Z
This publication is a glossary of terms used by the crop insurance industry. There are definitions for terms used in crop insurance documents and for terms pertaining to coverage levels, farming, reports, units and parties to contracts....
Key Issues | Department of Energy
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report: I11IG002RTC3WASTE-TO-ENERGY:KenKeriKey Issues Key
AdS Boundary Conditions and the Topologically Massive Gravity/CFT Correspondence
Skenderis, Kostas; Taylor, Marika; Rees, Balt C. van [Institute for Theoretical Physics, University of Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam (Netherlands)
2009-12-15T23:59:59.000Z
The AdS/CFT correspondence provides a new perspective on recurrent questions in General Relativity such as the allowed boundary conditions at infinity and the definition of gravitational conserved charges. Here we review the main insights obtained in this direction over the last decade and apply the new techniques to Topologically Massive Gravity. We show that this theory is dual to a non-unitary CFT for any value of its parameter mu and becomes a Logarithmic CFT at mu = 1.
Key-Insulated Symmetric Key Cryptography and Mitigating Attacks against Cryptographic Cloud Software
Dodis, Yevgeniy
Key-Insulated Symmetric Key Cryptography and Mitigating Attacks against Cryptographic Cloud- sociated cryptographic keys in their entirety. In this paper, we investigate key-insulated symmetric key. To illustrate the feasibility of key-insulated symmetric key cryptography, we also report a proof
Conformal Lifshitz Gravity from Holography
Tom Griffin; Petr Horava; Charles M. Melby-Thompson
2012-04-03T23:59:59.000Z
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.
DEFINITIONS / KEY WORDS POSSIBLE DUTIES EXAMPLE TITLE NAMES A person who works to someone else's
Baltisberger, Jay H.
these types of jobs are identified using only Custodian, Janitor, Housekeeper, etc. 1,2 Apprentice Apprentice Woodworker, Apprentice Weaver, Apprentice Blacksmith, etc 1,2 Office / Admin. Manage ment assist in training an apprentice or managing other workers. A highly skilled workman, artisan
Gauge Theory of Quantum Gravity
J. W. Moffat
1994-01-04T23:59:59.000Z
A gauge theory of quantum gravity is formulated, in which an internal, field dependent metric is introduced which non-linearly realizes the gauge fields on the non-compact group $SL(2,C)$, while linearly realizing them on $SU(2)$. Einstein's $SL(2,C)$ invariant theory of gravity emerges at low energies, since the extra degrees of freedom associated with the quadratic curvature and the internal metric only dominate at high energies. In a fixed internal metric gauge, only the the $SU(2)$ gauge symmetry is satisfied, the particle spectrum is identified and the Hamiltonian is shown to be bounded from below. Although Lorentz invariance is broken in this gauge, it is satisfied in general. The theory is quantized in this fixed, broken symmetry gauge as an $SU(2)$ gauge theory on a lattice with a lattice spacing equal to the Planck length. This produces a unitary and finite theory of quantum gravity.
Energy bounds in designer gravity
Amsel, Aaron J.; Marolf, Donald [Physics Department, UCSB, Santa Barbara, California 93106 (United States)
2006-09-15T23:59:59.000Z
We consider asymptotically anti-de Sitter gravity coupled to tachyonic scalar fields with mass at or slightly above the Breitenlohner-Freedman bound in d{>=}4 spacetime dimensions. The boundary conditions in these ''designer gravity'' theories are defined in terms of an arbitrary function W. We give a general argument that the Hamiltonian generators of asymptotic symmetries for such systems will be finite, and proceed to construct these generators using the covariant phase space method. The direct calculation confirms that the generators are finite and shows that they take the form of the pure gravity result plus additional contributions from the scalar fields. By comparing the generators to the spinor charge, we derive a lower bound on the gravitational energy when W has a global minimum and the Breitenlohner-Freedman bound is not saturated.
Counterterms, critical gravity and holography
Kallol Sen; Aninda Sinha; Nemani V. Suryanarayana
2012-05-18T23:59:59.000Z
We consider counterterms for odd dimensional holographic CFTs. These counterterms are derived by demanding cut-off independence of the CFT partition function on $S^d$ and $S^1 \\times S^{d-1}$. The same choice of counterterms leads to a cut-off independent Schwarzschild black hole entropy. When treated as independent actions, these counterterm actions resemble critical theories of gravity, i.e., higher curvature gravity theories where the additional massive spin-2 modes become massless. Equivalently, in the context of AdS/CFT, these are theories where at least one of the central charges associated with the trace anomaly vanishes. Connections between these theories and logarithmic CFTs are discussed. For a specific choice of parameters, the theories arising from counterterms are non-dynamical and resemble a DBI generalization of gravity. For even dimensional CFTs, analogous counterterms cancel log-independent cut-off dependence.
Key Opportunities and Challenges for Program Sustainability ...
Key Opportunities and Challenges for Program Sustainability Key Opportunities and Challenges for Program Sustainability Better Buildings Neighborhood Program, Peer Exchange Call:...
Fluid Gravity Engineering Rocket motor flow analysis
Anand, Mahesh
Fluid Gravity Engineering Capability Â· Rocket motor flow analysis -Internal (performance) -External (plume / contamination) Â· Effect on landing site (surface alteration) -In-depth flow through porous young scientists/engineers Fluid Gravity Engineering Ltd #12;
Tian, David Wenjie
2015-01-01T23:59:59.000Z
According to Lovelock's theorem, the Hilbert-Einstein and the Lovelock actions are indistinguishable from their field equations. However, they have different scalar-tensor counterparts, which correspond to the Brans-Dicke and the \\emph{Lovelock-Brans-Dicke} (LBD) gravities, respectively. In this paper the LBD model of alternative gravity with the Lagrangian density $\\mathscr{L}_{\\text{LBD}}=\\frac{1}{16\\pi}\\left[\\phi\\left(R+\\frac{a}{\\sqrt{-g}}{}^*RR + b\\mathcal{G}\\right)-\\frac{\\omega_{\\text L}}{\\phi}\
David Wenjie Tian; Ivan Booth
2015-03-02T23:59:59.000Z
According to Lovelock's theorem, the Hilbert-Einstein and the Lovelock actions are indistinguishable from their field equations. However, they have different scalar-tensor counterparts, which correspond to the Brans-Dicke and the \\emph{Lovelock-Brans-Dicke} (LBD) gravities, respectively. In this paper the LBD model of alternative gravity with the Lagrangian density $\\mathscr{L}_{\\text{LBD}}=\\frac{1}{16\\pi}[\\phi(R+\\frac{a}{\\sqrt{-g}}{}^*RR + b\\mathcal{G})-\\frac{\\omega_{\\text L}}{\\phi}\
Fyodor V. Tkachov
2000-01-11T23:59:59.000Z
A systematic framework for jet definition is developed from first principles of physical measurement, quantum field theory, and QCD. A jet definition is found which: is theoretically optimal in regard of both minimization of detector errors and inversion of hadronization; is similar to a cone algorithm with dynamically negotiated jet shapes and positions found via shape observables that generalize the thrust to any number of axes; involves no ad hoc conventions; allows a fast computer implementation [hep-ph/9912415]. The framework offers an array of options for systematic construction of quasi-optimal observables for specific applications.
Intrusive gravity currents in two-layer
Flynn, Morris R.
Intrusive gravity currents in two-layer stratified media Morris R. Flynn & Paul F. Linden Dept.avalanche.org/pictures #12;· `Microbursts' pose a non-trivial threat to airplane safety Introduction Impacts on human health;· Whereas gravity currents travel along a solid boundary, intrusive gravity currents or intrusions propagate
Gribov ambiguity in asymptotically AdS three-dimensional gravity
Anabalon, Andres [Departamento de Ciencias, Facultad de Artes Liberales, Facultad de Ingenieria y Ciencias, Universidad Adolfo Ibanez, Vina Del Mar (Chile); Canfora, Fabrizio [Centro de Estudios Cientificos (CECS), Casilla 1469, Valdivia (Chile); Giacomini, Alex; Oliva, Julio [Instituto de Fisica, Facultad de Ciencias, Universidad Austral de Chile, Valdivia (Chile)
2011-03-15T23:59:59.000Z
In this paper the zero modes of the de Donder gauge Faddeev-Popov operator for three-dimensional gravity with negative cosmological constant are analyzed. It is found that the AdS{sub 3} vacuum produces (infinitely many) normalizable smooth zero modes of the Faddeev-Popov operator. On the other hand, it is found that the Banados-Teitelboim-Zanelli black hole (including the zero mass black hole) does not generate zero modes. This differs from the usual Gribov problem in QCD where, close to the maximally symmetric vacuum, the Faddeev-Popov determinant is positive definite while 'far enough' from the vacuum it can vanish. This suggests that the zero mass Banados-Teitelboim-Zanelli black hole could be a suitable ground state of three-dimensional gravity with negative cosmological constant. Because of the kinematic origin of this result, it also applies for other covariant gravity theories in three dimensions with AdS{sub 3} as maximally symmetric solution, such as new massive gravity and topologically massive gravity. The relevance of these results for supersymmetry breaking is pointed out.
NREL: Energy Analysis - Key Activities
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Quantum Gravity and Precision Tests
C. P. Burgess
2006-06-24T23:59:59.000Z
This article provides a cartoon of the quantization of General Relativity using the ideas of effective field theory. These ideas underpin the use of General Relativity as a theory from which precise predictions are possible, since they show why quantum corrections to standard classical calculations are small. Quantum corrections can be computed controllably provided they are made for the weakly-curved geometries associated with precision tests of General Relativity, such as within the solar system or for binary pulsars. They also bring gravity back into the mainstream of physics, by showing that its quantization (at low energies) exactly parallels the quantization of other, better understood, non-renormalizable field theories which arise elsewhere in physics. Of course effective field theory techniques do not solve the fundamental problems of quantum gravity discussed elsewhere in these pages, but they do helpfully show that these problems are specific to applications on very small distance scales. They also show why we may safely reject any proposals to modify gravity at long distances if these involve low-energy problems (like ghosts or instabilities), since such problems are unlikely to be removed by the details of the ultimate understanding of gravity at microscopic scales.
Thomas Rauch
2006-07-11T23:59:59.000Z
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.
Antimatter, the SME, and Gravity
Jay D. Tasson
2012-12-07T23:59:59.000Z
A general field-theoretic framework for the analysis of CPT and Lorentz violation is provided by the Standard-Model Extension (SME). This work discusses a number of SME-based proposals for tests of CPT and Lorentz symmetry, including antihydrogen spectroscopy and antimatter gravity tests.
Antimatter, the SME, and Gravity
Tasson, Jay D
2012-01-01T23:59:59.000Z
A general field-theoretic framework for the analysis of CPT and Lorentz violation is provided by the Standard-Model Extension (SME). This work discusses a number of SME-based proposals for tests of CPT and Lorentz symmetry, including antihydrogen spectroscopy and antimatter gravity tests.
Liouville quantum gravity and KPZ
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 ...
Quantum Key Distribution with Qubit Pairs
Mohd Asad Siddiqui; Tabish Qureshi
2014-07-17T23:59:59.000Z
We propose a new Quantum Key Distribution method in which Alice sends pairs of qubits to Bob, each in one of four possible states. Bob uses one qubit to generate a secure key and the other to generate an auxiliary key. For each pair he randomly decides which qubit to use for which key. The auxiliary key has to be added to Bob's secure key in order to match Alice's secure key. This scheme provides an additional layer of security over the standard BB84 protocol.
COLLEGE AVE CAMPUS (CAC) KEY PICK UP
COLLEGE AVE CAMPUS (CAC) KEY PICK UP NOTE TO ALL STUDENTS: ONLY YOU CAN PICK UP YOUR KEY. You in and key pick up. If you are unable to pick up your key by 5:00 p.m. on September 1st , please make prior in Clothier Hall on CAC. Keys not picked up during the above-noted hours can be picked up at the Housing
Particlelike solutions in modified gravity: the Higgs monopole
Schlogel, Sandrine; Staelens, Francois; Fuzfa, Andre
2014-01-01T23:59:59.000Z
Higgs inflation has received a remarkable attention in the last few years due to its simplicity and predictive power. The key point of this model is the nonminimal coupling to gravity in unitary gauge. As such, this theory is in fact a scalar-tensor modification of gravity that needs to be studied also below the energy scales of inflation. Motivated by this goal, we study in great analytical and numerical detail the static and spherically symmetric solutions of the equations of motion in the presence of standard baryonic matter, called "Higgs monopoles" and presented in \\cite{monopole}. These particlelike solutions may arise naturally in tensor-scalar gravity with mexican hat potential and are the only globally regular asymptotically flat solutions with finite classical energy. In the case when the parameters of the potential are taken to be the ones of the standard model, we find that the deviations from general relativity are extremely small, especially for bodies of astrophysical size and density. This all...
Self-Gravity Driven Instabilities in the ISM
R. M. Hueckstaedt; J. H. Hunter Jr; R. V. E. Lovelace
2006-03-29T23:59:59.000Z
In order to understand star formation it is important to understand the dynamics of atomic and molecular clouds in the interstellar medium (ISM). Nonlinear hydrodynamic flows are a key component to the ISM. One route by which nonlinear flows arise is the onset and evolution of interfacial instabilities. Interfacial instabilities act to modify the interface between gas components at different densities and temperatures. Such an interface may be subject to a host of instabilities, including the Rayleigh-Taylor, Kelvin-Helmholtz, and Richtmyer-Meshkov instabilities. Recently, a new density interface instability was identified. This self-gravity interfacial instability (SGI) causes any displacement of the interface to gr ow on roughly a free-fall time scale, even when the perturbation wavelength is much less than the Jeans length. In previous work, we used numerical simulations to confirm the expectations of linear theory and examine the nonlinear evolution of the SGI. We now continue our study by generalizing our initial conditions to allow the acceleration due to self-gravity to be non-zero across the interface. We also consider the behaviour of the SGI for perturbation wavelengths near the Jeans wavelength. We conclude that the action of self-gravity across a density interface may play a significant role in the ISM either by fueling the growth of new instabilities or modifying the evolution of existing instabilities.
Intersecting hypersurfaces in anti-de Sitter and Lovelock gravity
Gravanis, Elias; Willison, Steven [Department of Physics, Kings College, Strand, London WC2R 2LS (United Kingdom); Department of Physics, Kings College, Strand, London WC2R 2LS (United Kingdom) and Centro de Estudios Cientificos (CECS), Casilla 1469, Valdivia (Chile)
2006-09-15T23:59:59.000Z
Colliding and intersecting hypersurfaces filled with matter (membranes) are studied in the Lovelock higher order curvature theory of gravity. Lovelock terms couple hypersurfaces of different dimensionalities, extending the range of possible intersection configurations. We restrict the study to constant curvature membranes in constant curvature anti-de Sitter (AdS) and dS background and consider their general intersections. This illustrates some key features which make the theory different from the Einstein gravity. Higher co-dimension membranes may lie at the intersection of co-dimension one hypersurfaces in Lovelock gravity; the hypersurfaces are located at the discontinuities of the first derivative of the metric, and they need not carry matter. The example of colliding membranes shows that general solutions can only be supported by (spacelike) matter at the collision surface, thus naturally conflicting with the dominant energy condition (DEC). The imposition of the DEC gives selection rules on the types of collision allowed. When the hypersurfaces do not carry matter, one gets a solitonlike configuration. Then, at the intersection one has a co-dimension two or higher membrane standing alone in AdS-vacuum space-time without conical singularities. Another result is that if the number of intersecting hypersurfaces goes to infinity the limiting space-time is free of curvature singularities if the intersection is put at the boundary of each AdS bulk.
Entropy and Energy: Toward a Definition of Physical Sustainability
Hermanowicz, Slawomir W
2005-01-01T23:59:59.000Z
usefulness of entropy-energy definition of sustainability asEntropy and Energy: Toward a Definition of Physicaland energy should be included in the desired definition of
A Natural Definition of Random Language Keith Wansbrough*
Wansbrough, Keith
Introduction Algorithmic Information Theory (AIT) provides definitions of randomness for strings A Natural Definition of Random Language Keith Wansbrough* October 13, 1995 Abstract We propose a natural definition
Formalism Locality in Quantum Theory and Quantum Gravity
Lucien Hardy
2008-04-01T23:59:59.000Z
We expect a theory of Quantum Gravity to be both probabilistic and have indefinite causal structure. Indefinite causal structure poses particular problems for theory formulation since many of the core ideas used in the usual approaches to theory construction depend on having definite causal structure. For example, the notion of a state across space evolving in time requires that we have some definite causal structure so we can define a state on a space-like hypersurface. We will see that many of these problems are mitigated if we are able to formulate the theory in a "formalism local" (or F-local) fashion. A formulation of a physical theory is said to be F-local if, in making predictions for any given arbitrary space-time region, we need only refer to mathematical objects pertaining to that region. This is a desirable property both on the grounds of efficiency and since, if we have indefinite causal structure, it is not clear how to select some other space-time region on which our calculations may depend. The usual ways of formulating physical theories (the time evolving state picture, the histories approach, and the local equations approach) are not F-local. We set up a framework for probabilistic theories with indefinite causal structure. This, the causaloid framework, is F-local. We describe how Quantum Theory can be formulated in the causaloid framework (in an F-local fashion). This provides yet another formulation of Quantum Theory. This formulation, however, may be particularly relevant to the problem of finding a theory of Quantum Gravity.
Particlelike solutions in modified gravity: the Higgs monopole
Sandrine Schlogel; Massimiliano Rinaldi; Francois Staelens; Andre Fuzfa
2014-08-21T23:59:59.000Z
Higgs inflation has received a remarkable attention in the last few years due to its simplicity and predictive power. The key point of this model is the nonminimal coupling to gravity in unitary gauge. As such, this theory is in fact a scalar-tensor modification of gravity that needs to be studied also below the energy scales of inflation. Motivated by this goal, we study in great analytical and numerical detail the static and spherically symmetric solutions of the equations of motion in the presence of standard baryonic matter, called "Higgs monopoles" and presented in 1305.2640. These particlelike solutions may arise naturally in tensor-scalar gravity with mexican hat potential and are the only globally regular asymptotically flat solutions with finite classical energy. In the case when the parameters of the potential are taken to be the ones of the standard model, we find that the deviations from general relativity are extremely small, especially for bodies of astrophysical size and density. This allows to derive a simplified description of the monopole, for which the metric inside the spherical matter distribution can be approximated by the standard metric of general relativity. We study how the properties of these monopoles depend on the strength of the nonminimal coupling to gravity and on the baryonic mass and compactness. An important and original result is the existence of a mechanism of resonant amplification of the Higgs field inside the monopole that comes into play for large nonminimal coupling. We show that this mechanism might degenerate into divergences of the Higgs field that reveal the existence of forbidden combinations of radius and baryonic energy density.
Axions in gravity with torsion
Oscar Castillo-Felisola; Cristobal Corral; Sergey Kovalenko; Ivan Schmidt; Valery E. Lyubovitskij
2015-04-13T23:59:59.000Z
We study a scenario allowing a solution of the strong charge parity problem via the Peccei-Quinn mechanism, implemented in gravity with torsion. In this framework there appears a torsion-related pseudoscalar field known as Kalb-Ramond axion. We compare it with the so-called Barbero-Immirzi axion recently proposed in the literature also in the context of the gravity with torsion. We show that they are equivalent from the viewpoint of the effective theory. The phenomenology of these torsion-descended axions is completely determined by the Planck scale without any additional model parameters. These axions are very light and very weakly interacting with ordinary matter. We briefly comment on their astrophysical and cosmological implications in view of the recent BICEP2 and Planck data.
Axions in gravity with torsion
Castillo-Felisola, Oscar; Kovalenko, Sergey; Schmidt, Ivan; Lyubovitskij, Valery E
2015-01-01T23:59:59.000Z
We study a scenario allowing a solution of the strong CP-problem via the Peccei-Quinn mechanism, implemented in gravity with torsion. In this framework there appears a torsion-related pseudoscalar field known as Kalb-Ramond axion. We compare it with the so called Barbero-Immirzi axion recently proposed in the literature also in the context of the gravity with torsion. We show that they are equivalent from the view point of the effective theory. The phenomenology of these torsion-descended axions is completely determined by the Planck scale without any additional model parameters. These axions are very light and very weakly interacting with ordinary matter. We briefly comment on their astrophysical and cosmological implications in view of the recent BICEP2 and Planck data.
Black holes in massive gravity
Babichev, Eugeny
2015-01-01T23:59:59.000Z
We review the black hole solutions of the ghost-free massive gravity theory and its bimetric extension and outline the main results on the stability of these solutions against small perturbations. Massive (bi)-gravity accommodates exact black hole solutions, analogous to those of General Relativity. In addition to these solutions, hairy black holes -- solutions with no correspondent in General Relativity -- have been found numerically, whose existence is a natural consequence of the absence of the Birkhoff's theorem in these theories. The existence of extra propagating degrees of freedom, makes the stability properties of these black holes richer and more complex than those of General Relativity. In particular, the bi-Schwarzschild black hole exhibits an unstable spherically symmetric mode, while the bi-Kerr geometry is also generically unstable, both against the spherical mode and against superradiant instabilities. If astrophysical black holes are described by these solutions, the superradiant instability o...
Answering Key Fuel Cycle Questions
Steven J. Piet; Brent W. Dixon; J. Stephen Herring; David E. Shropshire; Mary Lou Dunzik-Gougar
2003-10-01T23:59:59.000Z
The Advanced Fuel Cycle Initiative (AFCI) program has both “outcome” and “process” goals because it must address both waste already accumulating as well as completing the fuel cycle in connection with advanced nuclear power plant concepts. The outcome objectives are waste geological repository capacity and cost, energy security and sustainability, proliferation resistance, fuel cycle economics, and safety. The process objectives are readiness to proceed and adaptability and robustness in the face of uncertainties. A classic decision-making approach to such a multi-attribute problem would be to weight individual quantified criteria and calculate an overall figure of merit. This is inappropriate for several reasons. First, the goals are not independent. Second, the importance of different goals varies among stakeholders. Third, the importance of different goals is likely to vary with time, especially the “energy future.” Fourth, some key considerations are not easily or meaningfully quantifiable at present. Instead, at this point, we have developed 16 questions the AFCI program should answer and suggest an approach of determining for each whether relevant options improve meeting each of the program goals. We find that it is not always clear which option is best for a specific question and specific goal; this helps identify key issues for future work. In general, we suggest attempting to create as many win-win decisions (options that are attractive or neutral to most goals) as possible. Thus, to help clarify why the program is exploring the options it is, and to set the stage for future narrowing of options, we have developed 16 questions, as follows: · What are the AFCI program goals? · Which potential waste disposition approaches do we plan for? · What are the major separations, transmutation, and fuel options? · How do we address proliferation resistance? · Which potential energy futures do we plan for? · What potential external triggers do we plan for? · Should we separate uranium? · If we separate uranium, should we recycle it, store it or dispose of it? · Is it practical to plan to fabricate and handle “hot” fuel? · Which transuranic elements (TRU) should be separated and transmuted? · Of those TRU separated, which should be transmuted together? · Should we separate and/or transmute Cs and Sr isotopes that dominate near-term repository heating? · Should we separate and/or transmute very long-lived Tc and I isotopes? · Which separation technology? · What mix of transmutation technologies? · What fuel technology best supports the above decisions?
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Quantum Key Distribution with Screening and Analyzing
Won-Ho Kye
2006-10-04T23:59:59.000Z
We propose a quantum key distribution scheme by using screening angles and analyzing detectors which enable to notice the presence of Eve who eavesdrops the quantum channel, as the revised protocol of the recent quantum key distribution [Phys. Rev. Lett. 95, 040501 (2005)]. We discuss the security of the proposed quantum key distribution against various attacks including impersonation attack and Trojan Horse attack.
Lightweight Key Establishment for Distributed Networking Environments
Martin, Keith
/ COSIC Seminar 2007 Keith Martin #12;Lightweight Key Establishment/Introduction The plan 1. Wireless sensor networks 2. A key establishment framework 3. Key establishment for grids COSIC Seminar 2007 Keith Establishment/Wireless sensor networks The "classical" scenario COSIC Seminar 2007 Keith Martin #12;Lightweight
Born-Infeld gravity in three dimensions
Alishahiha, Mohsen [School of physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Naseh, Ali [School of physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Department of Physics, Sharif University of Technology, P.O. Box 11365-9161, Tehran (Iran, Islamic Republic of); Soltanpanahi, Hesam [School of physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); School of Physics and Centre for Theoretical Physics, University of the Witwatersrand, WITS 2050 Johannesburg (South Africa)
2010-07-15T23:59:59.000Z
In this paper we explore different aspects of three dimensional Born-Infeld as well as Born-Infeld-Chern-Simons gravity. We show that the models have anti-de Sitter and anti-de Sitter wave vacuum solutions. Moreover, we observe that although Born-Infeld-Chern-Simons gravity admits a logarithmic solution, Born-Infeld gravity does not, though it has a limiting logarithmic solution as we approach the critical point.
Quantum gravity computers: On the theory of computation with indefinite causal structure
Lucien Hardy
2007-01-05T23:59:59.000Z
A quantum gravity computer is one for which the particular effects of quantum gravity are relevant. In general relativity, causal structure is non-fixed. In quantum theory non-fixed quantities are subject to quantum uncertainty. It is therefore likely that, in a theory of quantum gravity, we will have indefinite causal structure. This means that there will be no matter of fact as to whether a particular interval is timelike or not. We study the implications of this for the theory of computation. Classical and quantum computations consist in ivolving the state of the computer through a sequence of time steps. This will, most likely, not be possible for a quantum gravity computer because the notion of a time step makes no sense if we have indefinite causal structure. We show that it is possible to set up a model for computation even in the absence of definite causal structure by using a certain framework (the causaloid formalism) that was developed for the purpose of correlating data taken in this type of situation. Corresponding to a physical theory is a causaloid, Lambda (this is a mathematical object containing information about the causal connections between different spacetime regions). A computer is given by the pair {Lambda, S} where S is a set of gates. Working within the causaloid formalism, we explore the question of whether universal quantum gravity computers are possible. We also examine whether a quantum gravity computer might be more powerful than a quantum (or classical) computer. In particular, we ask whether indefinite causal structure can be used as a computational resource.
Supersymmetry and Gravity in Noncommutative Field Theories
Victor O. Rivelles
2003-05-14T23:59:59.000Z
We discuss the renormalization properties of noncommutative supersymmetric theories. We also discuss how the gauge field plays a role similar to gravity in noncommutative theories.
Can Gravity Probe B usefully constrain torsion gravity theories?
Flanagan, Eanna E.; Rosenthal, Eran [Center for Radiophysics and Space Research, Cornell University, Ithaca, New York, 14853 (United States)
2007-06-15T23:59:59.000Z
In most theories of gravity involving torsion, the source for torsion is the intrinsic spin of matter. Since the spins of fermions are normally randomly oriented in macroscopic bodies, the amount of torsion generated by macroscopic bodies is normally negligible. However, in a recent paper, Mao et al. (arXiv:gr-qc/0608121) point out that there is a class of theories, including the Hayashi-Shirafuji (1979) theory, in which the angular momentum of macroscopic spinning bodies generates a significant amount of torsion. They further argue that, by the principle of action equals reaction, one would expect the angular momentum of test bodies to couple to a background torsion field, and therefore the precession of the Gravity Probe B gyroscopes should be affected in these theories by the torsion generated by the Earth. We show that in fact the principle of action equals reaction does not apply to these theories, essentially because the torsion is not an independent dynamical degree of freedom. We examine in detail a generalization of the Hayashi-Shirafuji theory suggested by Mao et al. called Einstein-Hayashi-Shirafuji theory. There are a variety of different versions of this theory, depending on the precise form of the coupling to matter chosen for the torsion. We show that, for any coupling to matter that is compatible with the spin transport equation postulated by Mao et al., the theory has either ghosts or an ill-posed initial-value formulation. These theoretical problems can be avoided by specializing the parameters of the theory and in addition choosing the standard minimal coupling to matter of the torsion tensor. This yields a consistent theory, but one in which the action equals reaction principle is violated, and in which the angular momentum of the gyroscopes does not couple to the Earth's torsion field. Thus, the Einstein-Hayashi-Shirafuji theory does not predict a detectable torsion signal for Gravity Probe B. There may be other torsion theories which do.
Gravity modeling of Cenozoic extensional basins, offshore Vietnam
Mauri, Steven Joseph
1993-01-01T23:59:59.000Z
(Yinggehai) basins. Gravity modeling results provide important clues to the controversial tectonic development of Southeast Asia during the Tertiary. Combined Bouguer and free-air gravity maps and residual gravity anomaly maps were generated for the study...
Karageorgis, Paschalis
13 Lyapunov stability Definition 13.1 (Positive definite). We say that V (x, y) is positive definite, if V (x, y) 0 at all points and if equality holds only at the origin. Definition 13.2 (Lyapunov functions). Suppose that V (x, y) is continuous and positive definite. Then we say that V is a Lyapunov
Negative mass solitons in gravity
Cebeci, Hakan; Sarioglu, Oezguer; Tekin, Bayram [Anadolu University, Department of Physics, Yunus Emre Campus, 26470, Eskisehir (Turkey); Department of Physics, Faculty of Arts and Sciences, Middle East Technical University, 06531, Ankara (Turkey)
2006-03-15T23:59:59.000Z
We first reconstruct the conserved (Abbott-Deser) charges in the spin-connection formalism of gravity for asymptotically (Anti)-de Sitter spaces, and then compute the masses of the AdS soliton and the recently found Eguchi-Hanson solitons in generic odd dimensions, unlike the previous result obtained for only five dimensions. These solutions have negative masses compared to the global AdS or AdS/Z{sub p} spacetimes. As a separate note, we also compute the masses of the recent even dimensional Taub-NUT-Reissner-Nordstroem metrics.
Ground Gravity Survey At Neal Hot Springs Geothermal Area (Colwell...
Technique Ground Gravity Survey Activity Date 2011 - 2011 Usefulness not indicated DOE-funding Unknown Exploration Basis Gravity surveys were conducted to gain a better...
airborne gravity survey: Topics by E-print Network
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Gravity CERN Preprints Summary: Modified gravity theories may provide an alternative to dark energy to explain cosmic acceleration. We argue that the observational program...
Reconstruction of Einstein-Aether Gravity from other Modified Gravity Models
Chayan Ranjit; Ujjal Debnath
2014-09-08T23:59:59.000Z
We briefly describe the modified Friedmann equations for Einstein-Aether gravity theory and we find the effective density and pressure. The purpose of our present work is to reconstruction of Einstein-Aether Gravity from other modified gravities like $f(T)$, $f(R)$, $f(G)$, $f(R,T)$ and $f(R,G)$ and check its viability. The scale factor is chosen in power law form. The free function $F(K)$ for Einstein-Aether gravity (where $K$ is proportional to $H^{2}$) have been found in terms for $K$ by the correspondence between Einstein-Aether gravity and other modified gravities and the nature of $F(K)$ vs $K$ have been shown graphically for every cases. Finally, we analyzed the stability of each reconstructed Einstein-Aether gravity model.
Conserved charges in 3D gravity
Blagojevic, M.; Cvetkovic, B. [University of Belgrade, Institute of Physics, P. O. Box 57, 11001 Belgrade (Serbia)
2010-06-15T23:59:59.000Z
The covariant canonical expression for the conserved charges, proposed by Nester, is tested on several solutions in three-dimensional gravity with or without torsion and topologically massive gravity. In each of these cases, the calculated values of energy momentum and angular momentum are found to satisfy the first law of black hole thermodynamics.
The Superheavy Elements and Anti-Gravity
Anastasovski, Petar K. [Department of Physics, Faculty of Technology and Metallurgy, Saints Cyril and Methodius University, Skopje (Macedonia, The Former Yugoslav Republic of)
2004-02-04T23:59:59.000Z
The essence of any propulsion concept is to overcome gravity. Anti-gravity is a natural means to achieve this. Thus, the technology to pursue anti-gravity, by using superheavy elements, may provide a new propulsion paradigm. The theory of superluminal relativity provides a hypothesis for existence of elements with atomic number up to Z = 145, some of which may possess anti-gravity properties. Analysis results show that curved space-time exists demonstrating both gravitic and anti-gravitic properties not only around nuclei but inside the nuclei as well. Two groups of elements (Z < 64 and 63 < Z <145) exist that demonstrate these capabilities. The nuclei of the first group of elements have the masses with only the property of gravity. The nuclei of the elements of the second group have the masses with both properties: gravity and anti-gravity in two different ranges of curved space-time around the nuclei.. The hypothetical element with Z = 145 is the unique among all elements whose nucleus has only anti-gravity property. It is proposed that this element be named Hawking, in honour of Stephen W. Hawking.
Dual Accretion Disks in Alternate Gravity Theories
James S. Graber
1997-12-15T23:59:59.000Z
The interior of gravitationally collapsed objects in alternate theories of gravity in which event horizons and singularities do not occur in strong field gravity were generically investigated. These objects, called red holes, were found to contain dynamic configurations of matter, radiation and spacetime similar to inside out accretion disks well inside the photon orbit. Applications to astrophysical phenomena are briefly described.
Threat Mitigation: The Gravity Tractor
Russell Schweickart; Clark Chapman; Dan Durda; Piet Hut
2006-08-15T23:59:59.000Z
The Gravity Tractor (GT) is a fully controlled asteroid deflection concept using the mutual gravity between a robotic spacecraft and an asteroid to slowly accelerate the asteroid in the direction of the "hovering" spacecraft. Based on early warning, provided by ground tracking and orbit prediction, it would be deployed a decade or more prior to a potential impact. Ion engines would be utilized for both the rendezvous with the asteroid and the towing phase. Since the GT does not dock with or otherwise physically contact the asteroid during the deflection process there is no requirement for knowledge of the asteroid's shape, composition, rotation state or other "conventional" characteristics. The GT would first reduce the uncertainty in the orbit of the asteroid via Earth tracking of its radio transponder while station keeping with the asteroid. If, after analysis of the more precise asteroid orbit a deflection is indeed indicated, the GT would "hover" above the surface of the asteroid in the direction of the required acceleration vector for a duration adequate to achieve the desired velocity change. The orbit of the asteroid is continuously monitored throughout the deflection process and the end state is known in real time. The performance envelope for the GT includes most NEOs which experience close gravitational encounters prior to impact and those below 150-200 meters in diameter on a direct Earth impact trajectory.
Solar System constraints to nonminimally coupled gravity
Orfeu Bertolami; Riccardo March; Jorge Páramos
2013-06-05T23:59:59.000Z
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.
Counterfactual quantum key distribution with high efficiency
Sun Ying [State Key Laboratory of Networking and SwitchingTechnology, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Beijing Electronic Science and Technology Institute, Beijing 100070 (China); Wen Qiaoyan [State Key Laboratory of Networking and SwitchingTechnology, Beijing University of Posts and Telecommunications, Beijing 100876 (China)
2010-11-15T23:59:59.000Z
In a counterfactual quantum key distribution scheme, a secret key can be generated merely by transmitting the split vacuum pulses of single particles. We improve the efficiency of the first quantum key distribution scheme based on the counterfactual phenomenon. This scheme not only achieves the same security level as the original one but also has higher efficiency. We also analyze how to achieve the optimal efficiency under various conditions.
Florida Keys Electric Cooperative- Residential Rebate Program
Broader source: Energy.gov [DOE]
Florida Keys Electric Cooperative offers residential members rebates for installing energy efficient measures. To qualify for rebates, members must first call FKEC and make an appointment for a...
Brain Receptor Structures Key to Future Therapeutics
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Brain Receptor Structures Key to Future Therapeutics Print With an aging population in America, it is more important than ever to discover ways to treat or prevent diseases...
Definition RX Evaluate Kernels K-2d K-1d Change By definition undefined
Theiler, James
Definition RX Evaluate Kernels K-2d K-1d Change By def·i·ni·tion undefined Adventures in anomaly Alamos National Laboratory Research supported by the United States Department of Energy through the Los Alamos Laboratory Directed Research and Development (LDRD) Program. #12;Theiler LA-UR-14-24429 Definition
Orlando Luongo; Hernando Quevedo
2015-07-23T23:59:59.000Z
The existence of current-time universe's acceleration is usually modeled by means of two main strategies. The first makes use of a dark energy barotropic fluid entering \\emph{by hand} the energy-momentum tensor of Einstein's theory. The second lies on extending the Hilbert-Einstein action giving rise to the class of extended theories of gravity. In this work, we propose a third approach, derived as an intrinsic geometrical effect of space-time, which provides repulsive regions under certain circumstances. We demonstrate that the effects of repulsive gravity naturally emerge in the field of a homogeneous and isotropic universe. To this end, we use an invariant definition of repulsive gravity based upon the behavior of the curvature eigenvalues. Moreover, we show that repulsive gravity counterbalances the standard gravitational attraction influencing both late and early times of the universe evolution. This phenomenon leads to the present speed up and to the fast expansion due to the inflationary epoch. In so doing, we are able to unify both dark energy and inflation in a single scheme, showing that the universe changes its dynamics when ${\\ddot H\\over H}=-2\\dot H$, at the repulsion onset time where this condition is satisfied. Further, we argue that the spatial scalar curvature can be taken as vanishing because it does not affect at all the emergence of repulsive gravity. We check the goodness of our approach through two cosmological fits involving the most recent union 2.1 supernova compilation.
Modified Gravity N-body Code Comparison Project
Hans A. Winther; Fabian Schmidt; Alexandre Barreira; Christian Arnold; Sownak Bose; Claudio Llinares; Marco Baldi; Bridget Falck; Wojciech A. Hellwing; Kazuya Koyama; Baojiu Li; David F. Mota; Ewald Puchwein; Robert Smith; Gong-Bo Zhao
2015-06-21T23:59:59.000Z
Self-consistent ${\\it N}$-body simulations of modified gravity models are a key ingredient to obtain rigorous constraints on deviations from General Relativity using large-scale structure observations. This paper provides the first detailed comparison of the results of different ${\\it N}$-body codes for the $f(R)$, DGP, and Symmetron models, starting from the same initial conditions. We find that the fractional deviation of the matter power spectrum from $\\Lambda$CDM agrees to better than $1\\%$ up to $k \\sim 5-10~h/{\\rm Mpc}$ between the different codes. These codes are thus able to meet the stringent accuracy requirements of upcoming observational surveys. All codes are also in good agreement in their results for the velocity divergence power spectrum, halo abundances and halo profiles. We also test the quasi-static limit, which is employed in most modified gravity ${\\it N}$-body codes, for the Symmetron model for which the most significant non-static effects among the models considered are expected. We conclude that this limit is a very good approximation for all of the observables considered here.
Secure key distribution by swapping quantum entanglement
Song, Daegene [National Institute of Standards and Technology, 100 Bureau Drive, MS 8910, Gaithersburg, Maryland 20899 (United States)
2004-03-01T23:59:59.000Z
We report two key distribution schemes achieved by swapping quantum entanglement. Using two Bell states, two bits of secret key can be shared between two distant parties that play symmetric and equal roles. We also address eavesdropping attacks against the schemes.
On quantum key distribution using ququarts
Kulik, S. P., E-mail: Sergei.Kulik@gmail.com; Shurupov, A. P. [Moscow State University (Russian Federation)
2007-05-15T23:59:59.000Z
A comparative analysis of quantum key distribution protocols using qubits and ququarts as information carriers is presented. Several schemes of incoherent attacks that can be used by an eavesdropper to obtain secret information are considered. The errors induced by the eavesdropper are analyzed for several key distribution protocols.
A Natural Definition of Random Language Keith Wansbrough \\Lambda
Wansbrough, Keith
definition. 1 Introduction Algorithmic Information Theory (AIT) provides definitions of randomnessA Natural Definition of Random Language Keith Wansbrough \\Lambda October 13, 1995 Abstract We propose a natural definition of random language, based on the standard AIT definitions of random string
Quantum Gravity effect on neutrino oscillations in a strong gravitational field
Jonathan Miller; Roman Pasechnik
2014-11-14T23:59:59.000Z
In the framework of quantum field theory, a graviton interacts locally with a quantum state having definite mass, i.e. the gravitational mass eigenstate, while a weak boson interacts with a state having definite flavor, i.e. the flavor eigenstate. An interaction of a neutrino with an energetic graviton may trigger the collapse of the neutrino to a definite mass eigenstate with probability expressed in terms of PMNS mixing matrix elements. Thus, gravitons would induce quantum decoherence of a coherent neutrino flavor state similarly to how weak bosons induce quantum decoherence of a neutrino in a definite mass state. We demonstrate that such an essentially quantum gravity effect may have strong consequences for neutrino oscillation phenomena in astrophysics due to relatively large scattering cross sections of relativistic neutrinos undergoing large-angle radiation of energetic gravitons in gravitational field of a classical massive source (i.e. the quasi-classical case of gravitational Bethe-Heitler scattering). This graviton-induced {\\em decoherence} is compared to {\\em decoherence} due to propagation in the presence of the Earth matter effect. Based on this study, we propose a new technique for the indirect detection of energetic gravitons by measuring the flavor composition of astrophysical neutrinos.
Emergent Horava gravity in graphene
G. E. Volovik; M. A. Zubkov
2013-07-07T23:59:59.000Z
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.
Dimensional Reduction in Quantum Gravity
G. 't Hooft
2009-03-20T23:59:59.000Z
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.
Tom Fleming; Mark Gross; Ray Renken
1994-01-04T23:59:59.000Z
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.
Gravity-Induced Vacuum Dominance
Lima, William C. C.; Vanzella, Daniel A. T. [Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, Caixa Postal 369, CEP 15980-900, Sao Carlos, SP (Brazil)
2010-04-23T23:59:59.000Z
It has been widely believed that, except in very extreme situations, the influence of gravity on quantum fields should amount to just small, subdominant contributions. This view seemed to be endorsed by the seminal results obtained over the last decades in the context of renormalization of quantum fields in curved spacetimes. Here, however, we argue that this belief is false by showing that there exist well-behaved spacetime evolutions where the vacuum energy density of free quantum fields is forced, by the very same background spacetime, to become dominant over any classical energy-density component. By estimating the time scale for the vacuum energy density to become dominant, and therefore for backreaction on the background spacetime to become important, we argue that this (infrared) vacuum dominance may bear unexpected astrophysical and cosmological implications.
Newtonian gravity, red shift, confinement, asymptotic freedom and quarks oscillations
G. Quznetsov
2008-10-18T23:59:59.000Z
Quarks oscillations give the Newtonian gravity law, the red shift, the confinement and the asymptotic freedom.
Loop Quantum Gravity 1. Classical framework : Ashtekar-Barbero connection
Sart, Remi
gravity Why Quantum Gravity ? Gravitation vs. Quantum Physics : the two infinities Gravitation : large Quantum Gravity ? Gravitation vs. Quantum Physics : the two infinities Gravitation : large scales-perturbative renormalization Gravity is not a fundamental theory but it is effective (law energy) Â· it has to be modified
Fractal Structure of Loop Quantum Gravity
Leonardo Modesto
2008-12-11T23:59:59.000Z
In this paper we have calculated the spectral dimension of loop quantum gravity (LQG) using simple arguments coming from the area spectrum at different length scales. We have obtained that the spectral dimension of the spatial section runs from 2 to 3, across a 1.5 phase, when the energy of a probe scalar field decrees from high to low energy. We have calculated the spectral dimension of the space-time also using results from spin-foam models, obtaining a 2-dimensional effective manifold at hight energy. Our result is consistent with other two approach to non perturbative quantum gravity: causal dynamical triangulation and asymptotic safety quantum gravity.
CDT meets Horava-Lifshitz gravity
J. Ambjorn; A. Gorlich; S. Jordan; J. Jurkiewicz; R. Loll
2010-04-06T23:59:59.000Z
The theory of causal dynamical triangulations (CDT) attempts to define a nonperturbative theory of quantum gravity as a sum over space-time geometries. One of the ingredients of the CDT framework is a global time foliation, which also plays a central role in the quantum gravity theory recently formulated by Ho\\v{r}ava. We show that the phase diagram of CDT bears a striking resemblance with the generic Lifshitz phase diagram appealed to by Ho\\v{r}ava. We argue that CDT might provide a unifying nonperturbative framework for anisotropic as well as isotropic theories of quantum gravity.
Ning Wu
2012-07-11T23:59:59.000Z
When we discuss problems on gravity, we can not avoid some fundamental physical problems, such as space-time, inertia, and inertial reference frame. The goal of this paper is to discuss the logic system of gravity theory and the problems of space-time, inertia, and inertial reference frame. The goal of this paper is to set up the theory on space-time in gauge theory of gravity. Based on this theory, it is possible for human kind to manipulate physical space-time on earth, and produce a machine which can physically prolong human's lifetime.
Consistent Query Answering Of Conjunctive Queries Under Primary Key Constraints
Pema, Enela
2014-01-01T23:59:59.000Z
Queries and Primary Key Constraints . . . . . . . . . .of Employee w.r.t. the primary key SSN ? {name, salary} . .query answering under primary keys: a characterization of
Captured key electrical safety lockout system
Darimont, Daniel E. (Aurora, IL)
1995-01-01T23:59:59.000Z
A safety lockout apparatus for an electrical circuit includes an electrical switch, a key, a lock and a blocking mechanism. The electrical switch is movable between an ON position at which the electrical circuit is energized and an OFF position at which the electrical circuit is deactivated. The lock is adapted to receive the key and is rotatable among a plurality of positions by the key. The key is only insertable and removable when the lock is at a preselected position. The lock is maintained in the preselected position when the key is removed from the lock. The blocking mechanism physically maintains the switch in its OFF position when the key is removed from the lock. The blocking mechanism preferably includes a member driven by the lock between a first position at which the electrical switch is movable between its ON and OFF positions and a second position at which the member physically maintains the electrical switch in its OFF position. Advantageously, the driven member's second position corresponds to the preselected position at which the key can be removed from and inserted into the lock.
Captured key electrical safety lockout system
Darimont, D.E.
1995-10-31T23:59:59.000Z
A safety lockout apparatus for an electrical circuit includes an electrical switch, a key, a lock and a blocking mechanism. The electrical switch is movable between an ON position at which the electrical circuit is energized and an OFF position at which the electrical circuit is deactivated. The lock is adapted to receive the key and is rotatable among a plurality of positions by the key. The key is only insertable and removable when the lock is at a preselected position. The lock is maintained in the preselected position when the key is removed from the lock. The blocking mechanism physically maintains the switch in its OFF position when the key is removed from the lock. The blocking mechanism preferably includes a member driven by the lock between a first position at which the electrical switch is movable between its ON and OFF positions and a second position at which the member physically maintains the electrical switch in its OFF position. Advantageously, the driven member`s second position corresponds to the preselected position at which the key can be removed from and inserted into the lock. 7 figs.
Experimental study of high speed polarization-coding quantum key distribution with sifted-key
and links 1. C. H. Bennet and G. Brassard, "Quantum cryptography: Public key distribution and coin tossing
September 11, 2012 NIST Key Management Workshop 2012 Secure Key Storage
September 11, 2012 NIST Key Management Workshop 2012 Secure Key Storage and True Random Number Storage via PUFs - Main Idea - Reliability - Randomness -- InstantiationsInstantiations 3. True Random, including side channel resistance ° Trusted security policy routines ° Secure and authentic key storage
Bounds on quantum communication via Newtonian gravity
D. Kafri; G. J. Milburn; J. M. Taylor
2014-10-08T23:59:59.000Z
Newtonian gravity yields specific observable consequences, the most striking of which is the emergence of a $1/r^2$ force. In so far as communication can arise via such interactions between distant particles, we can ask what would be expected for a theory of gravity that only allows classical communication. Many heuristic suggestions for gravity-induced decoherence have this restriction implicitly or explicitly in their construction. Here we show that communication via a $1/r^2$ force has a minimum noise induced in the system when the communication cannot convey quantum information, in a continuous time analogue to Bell's inequalities. Our derived noise bounds provide tight constraints from current experimental results on any theory of gravity that does not allow quantum communication.
Zhan, Lang; Yortsos, Yanis
2000-09-11T23:59:59.000Z
A new gravity finger model was proposed in this report in the absence of interfacial tension but in the presence of gravities. This model considered differences in density and viscosity of the two fluids. Thus, it was able to represent both stable and unstable displacements, and the finger development along either the upper or the bottom walls of a channel. This solution recovers the Saffman - Taylar solution if gravity is neglected. The results of the solution are very similar to the solutions proposed by Brener et al. for the gravity number up to 10. The solution provided in this work only has one free parameter while the solution of Brener et al. has three.
Gravity waves from vortex dipoles and jets
Wang, Shuguang
2009-05-15T23:59:59.000Z
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...
State sum models for quantum gravity
John W. Barrett
2000-10-12T23:59:59.000Z
This paper reviews the construction of quantum field theory on a 4-dimensional spacetime by combinatorial methods, and discusses the recent developments in the direction of a combinatorial construction of quantum gravity.
Energy conditions in f(R) gravity
Santos, J. [Universidade Federal do Rio Grande do Norte, Departamento de Fisica C.P. 1641, 59072-970 Natal-Rio Grande do Norte (Brazil); Departamento de Astronomia, Observatorio Nacional, 20921-400 Rio de Janeiro-Rio de Janeiro (Brazil); Centro Brasileiro de Pesquisas Fisicas, Rua Dr. Xavier Sigaud 150, 22290-180 Rio de Janeiro-Rio de Janeiro (Brazil); Alcaniz, J. S.; Carvalho, F. C. [Departamento de Astronomia, Observatorio Nacional, 20921-400 Rio de Janeiro-Rio de Janeiro (Brazil); Reboucas, M. J. [Centro Brasileiro de Pesquisas Fisicas, Rua Dr. Xavier Sigaud 150, 22290-180 Rio de Janeiro-Rio de Janeiro (Brazil)
2007-10-15T23:59:59.000Z
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 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.
Cosmology of modified (but second order) gravity
Tomi S. Koivisto
2009-10-21T23:59:59.000Z
This is a brief review of modified gravity cosmologies. Generically extensions of gravity action involve higher derivative terms, which can result in ghosts and instabilities. There are three ways to circumvent this: Chern-Simons terms, first order variational principle and nonlocality. We consider recent cosmological applications of these three classes of modified gravity models, in particular to the dark energy problem. The viable parameter spaces can be very efficiently constrained by taking into account cosmological data from all epochs in addition to Solar system tests and stability considerations. We make some new remarks concerning so called algebraic scalar-tensor theories, biscalar reformulation of nonlocal actions involving the inverse d'Alembertian, and a possible covariant formulation holographic cosmology with nonperturbative gravity.
Energy conditions in f(R)-gravity
J. Santos; J. S. Alcaniz; M. J. Reboucas; F. C. Carvalho
2007-09-06T23:59:59.000Z
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.
Test particle motion in modified gravity theories
Mahmood Roshan
2013-02-05T23:59:59.000Z
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. $\
A new vacuum for Loop Quantum Gravity
Bianca Dittrich; Marc Geiller
2015-05-05T23:59:59.000Z
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.
Antimatter-Gravity Couplings, and Lorentz Symmetry
Tasson, Jay D
2015-01-01T23:59:59.000Z
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).
Antimatter-Gravity Couplings, and Lorentz Symmetry
Jay D. Tasson
2015-01-27T23:59:59.000Z
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).
Oblique reflections of internal gravity wave beams
Karimi, Hussain H. (Hussain Habibullah)
2012-01-01T23:59:59.000Z
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 ...
Gravity Recovery and Interior Laboratory (GRAIL) Launch
Gravity Recovery and Interior Laboratory (GRAIL) Launch Press Kit/AUGUst 2011 #12;http of its four channels to AC-3, making each channel's secondary audio MPEG 1 Layer II. For digital downlink
Anisotropic induced gravity and inflationary universe
W. F. Kao
2006-12-09T23:59:59.000Z
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.
Gravity waves from cosmic bubble collisions
Salem, Michael P.; Saraswat, Prashant; Shaghoulian, Edgar, E-mail: mpsalem@stanford.edu, E-mail: ps88@stanford.edu, E-mail: edgars@stanford.edu [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University, Stanford, California 94305 (United States)
2013-02-01T23:59:59.000Z
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.
Key Implications of the Global Economic Environment
Lansky, Joshua
Key Implications of the Global Economic Environment For PCT Filings: A Survey of the Issues DMI...............................................................................9 Annex 1: Incentives for Patent Filing: The Analytical Framework...........................11 I-1 Intellectual property, innovation, and economic growth.................................13 2-2 Individual
Extracting secret keys from integrated circuits
Lim, Daihyun, 1976-
2004-01-01T23:59:59.000Z
Modern cryptographic protocols are based on the premise that only authorized participants can obtain secret keys and access to information systems. However, various kinds of tampering methods have been devised to extract ...
BACK TO BASICS: YOUR KEYS TO SAFE
Kirschner, Denise
BACK TO BASICS: YOUR KEYS TO SAFE DRIVING FINE-TUNE THE FUNDAMENTALS DRIVE SAFELY WORK WEEK: FRIDAY an occasional refresher. In fact, most company fleet safety programs emphasize basic skills and defensive
Mutual Dependence for Secret Key Agreement
Chan, Chung
A mutual dependence expression is established for the secret key agreement problem when all users are active. In certain source networks, the expression can be interpreted as certain notions of connectivity and network ...
Pushing the Frontier of High-Definition Ion Mobility Spectrometry...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
the Frontier of High-Definition Ion Mobility Spectrometry Using FAIMS. Pushing the Frontier of High-Definition Ion Mobility Spectrometry Using FAIMS. Abstract: Differential ion...
BLOCK DIAGONALLY DOMINANT POSITIVE DEFINITE APPROXIMATE FILTERS AND SMOOTHERS
BLOCK DIAGONALLY DOMINANT POSITIVE DEFINITE APPROXIMATE FILTERS AND SMOOTHERS Running title: BLOCK the loss of positive definiteness in the approximate equations. Therefore previous analyses have
Entropy and Energy: Toward a Definition of Physical Sustainability
Hermanowicz, Slawomir W
2005-01-01T23:59:59.000Z
of entropy-energy definition of sustainability as well asand Energy: Toward a Definition of Physical Sustainabilityto assess the sustainability is based on the energy. This
Mathematical definition of quantum field theory on a manifold
A. V. Stoyanovsky
2009-11-21T23:59:59.000Z
We give a mathematical definition of quantum field theory on a manifold, and definition of quantization of a classical field theory given by a variational principle.
Multipartite secret key distillation and bound entanglement
Remigiusz Augusiak; Pawel Horodecki
2009-09-25T23:59:59.000Z
Recently it has been shown that quantum cryptography beyond pure entanglement distillation is possible and a paradigm for the associated protocols has been established. Here we systematically generalize the whole paradigm to the multipartite scenario. We provide constructions of new classes of multipartite bound entangled states, i.e., those with underlying twisted GHZ structure and nonzero distillable cryptographic key. We quantitatively estimate the key from below with help of the privacy squeezing technique.
Multipartite secret key distillation and bound entanglement
Augusiak, Remigiusz; Horodecki, Pawel [Faculty of Applied Physics and Mathematics, Gdansk University of Technology, Narutowicza 11/12, 80-952 Gdansk (Poland) and ICFO-Institute Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona) (Spain); Faculty of Applied Physics and Mathematics, Gdansk University of Technology, Narutowicza 11/12, 80-952 Gdansk (Poland)
2009-10-15T23:59:59.000Z
Recently it has been shown that quantum cryptography beyond pure entanglement distillation is possible and a paradigm for the associated protocols has been established. Here we systematically generalize the whole paradigm to the multipartite scenario. We provide constructions of new classes of multipartite bound entangled states, i.e., those with underlying twisted Greenberger-Horne-Zeilinger (GHZ) structure and nonzero distillable cryptographic key. We quantitatively estimate the key from below with the help of the privacy squeezing technique.
The shape dynamics description of gravity
Tim Koslowski
2015-01-13T23:59:59.000Z
Classical gravity can be described as a relational dynamical system without ever appealing to spacetime or its geometry. This description is the so-called shape dynamics description of gravity. The existence of relational first principles from which the shape dynamics description of gravity can be derived is a motivation to consider shape dynamics (rather than GR) as the fundamental description of gravity. Adopting this point of view leads to the question: What is the role of spacetime in the shape dynamics description of gravity? This question contains many aspects: Compatibility of shape dynamics with the description of gravity in terms of spacetime geometry, the role of local Minkowski space, universality of spacetime geometry and the nature of quantum particles, which can no longer be assumed to be irreducible representations of the Poincare group. In this contribution I derive effective spacetime structures by considering how matter fluctuations evolve along with shape dynamics. This evolution reveals an "experienced spacetime geometry." This leads (in an idealized approximation) to local Minkowski space and causal relations. The small scale structure of the emergent geometric picture depends on the specific probes used to experience spacetime, which limits the applicability of effective spacetime to describe shape dynamics. I conclude with discussing the nature of quantum fluctuations (particles) in shape dynamics and how local Minkowski spacetime emerges from the evolution of quantum particles.
Gravity as Quantum Foam In-Flow
Reginald T Cahill
2003-07-01T23:59:59.000Z
The new information-theoretic Process Physics provides an explanation of space as a quantum foam system in which gravity is an inhomogeneous flow of the quantum foam into matter. The older Newtonian and General Relativity theories for gravity are analysed. It is shown that Newtonian gravity may be written in the form of an in-flow. General Relativity is also analysed as an in-flow, for those cases where it has been tested. An analysis of various experimental data demonstrates that absolute motion relative to space has been observed by Michelson and Morley, Miller, Illingworth, Jaseja et al, Torr and Kolen, and by DeWitte. The Dayton Miller and Roland DeWitte data also reveal the in-flow of space into matter which manifests as gravity. The experimental data suggests that the in-flow is turbulent, which amounts to the observation of a gravitational wave phenomena. A new in-flow theory of gravity is proposed which passes all the tests that General Relativity was claimed to have passed, but as well the new theory suggests that the so-called spiral galaxy rotation-velocity anomaly may be explained without the need of `dark matter'. Various other gravitational anomalies also appear to be explainable. Newtonian gravity appears to be strictly valid only outside of spherically symmetric matter systems.
Effects of a Highway Improvement Project on Florida key Deer
Parker, Israel D.; Braden, Anthony W.; Lopez, Roel R.; Silvy, Nova J.; Davis, Donald S.; Owen, Catherine B.
2007-01-01T23:59:59.000Z
the primary inter-island roadway in the Florida Keys. DVCsprimary source of mortality for the endangered Florida Key
Powerful evidences for supporting the claim that gamma-ray burst redshifts are gravity-generated
Fu-Gao Song
2012-06-24T23:59:59.000Z
At present, it is widely believed that the phenomenon of the gamma-ray burst redshift is cosmological origin. From a theoretical point of view, this redshift has either a cosmological or a cause that is related to gravity. However, the question of whether the gamma-ray burst redshift has a cosmological origin or not should be answerable in no uncertain terms because both the spectrum characteristics and the count distribution law arising from the two distinct settings are completely different. If the redshift of GRB is generated by gravity, then the afterglow spectrum will certainly contain both the gravitational redshits (containing emission and absorption feature) and Doppler absorption redshift, and hold a definite relation between the two redshifts. In this paper, we present nine direct and decisive evidences to show that the gamma-ray burst redshift is indeed generated by gravity of neutron stars in their merging process; in which, 114 GRBs' redshifts showed that the statistical count distribution law for the two kinds redshift is the same (with errors less than 1.5%), and 74 spectral line redshifts of two GRBs showed that the relation between the two kinds redshift is completely correct (with errors less than 0.0061%).
Definition of a 'Zero Net Energy' Community
Carlisle, N.; Van Geet, O.; Pless, S.
2009-11-01T23:59:59.000Z
This document provides a definition for a net zero-energy community. A community that offsets all of its energy use from renewables available within the community's built environment.
Department of Bioengineering Definition of Biomedical Engineering
is a discipline that advances knowledge in engineering, biology and medicine, and improves human health throughDepartment of Bioengineering Definition of Biomedical Engineering Biomedical engineering cross-disciplinary activities that integrate the engineering sciences with the biomedical sciences
Quantum gravity and inventory accumulation
Scott Sheffield
2011-08-10T23:59:59.000Z
We begin by studying inventory accumulation at a LIFO (last-in-first-out) retailer with two products. In the simplest version, the following occur with equal probability at each time step: first product ordered, first product produced, second product ordered, second product produced. The inventory thus evolves as a simple random walk on Z^2. In more interesting versions, a p fraction of customers orders the "freshest available" product regardless of type. We show that the corresponding random walks scale to Brownian motions with diffusion matrices depending on p. We then turn our attention to the critical Fortuin-Kastelyn random planar map model, which gives, for each q>0, a probability measure on random (discretized) two-dimensional surfaces decorated by loops, related to the q-state Potts model. A longstanding open problem is to show that as the discretization gets finer, the surfaces converge in law to a limiting (loop-decorated) random surface. The limit is expected to be a Liouville quantum gravity surface decorated by a conformal loop ensemble, with parameters depending on q. Thanks to a bijection between decorated planar maps and inventory trajectories (closely related to bijections of Bernardi and Mullin), our results about the latter imply convergence of the former in a particular topology. A phase transition occurs at p = 1/2, q=4.
Encoding field theories into gravities
Aoki, Sinya; Onogi, Tetsuya
2015-01-01T23:59:59.000Z
We propose a method, which encodes the information of a $d$ dimensional quantum field theory into a $d+1$ dimensional gravity in the $1/N$ expansion. We first construct a $d+1$ dimensional field theory from the $d$ dimensional one via the gradient flow equation, whose flow time $t$ represents the energy scale of the system such that $t\\rightarrow 0$ corresponds to the ultra-violet (UV) while $t\\rightarrow\\infty$ to the infra-red (IR). We then define the induced metric from $d+1$ dimensional field operators. We show that the metric defined in this way becomes classical in the large $N$ limit, in a sense that quantum fluctuations of the metric are suppressed as $1/N$ due to the large $N$ factorization property. As a concrete example, we apply our method to the O(N) non-linear $\\sigma$ model in two dimensions. We calculate the induced metric in three dimensions, which is shown to describe De Sitter (dS) or Anti De Sitter (AdS) space in the massless limit, where the mass is dynamically generated in the O(N) non-l...
Universality of Gravity from Entanglement
Brian Swingle; Mark Van Raamsdonk
2014-05-12T23:59:59.000Z
The entanglement "first law" in conformal field theories relates the entanglement entropy for a ball-shaped region to an integral over the same region involving the expectation value of the CFT stress-energy tensor, for infinitesimal perturbations to the CFT vacuum state. In recent work, this was exploited at leading order in $N$ in the context of large N holographic CFTs to show that any geometry dual to a perturbed CFT state must satisfy Einstein's equations linearized about pure AdS. In this note, we investigate the implications of the leading 1/N correction to the exact CFT result. We show that these corrections give rise to the source term for the gravitational equations: for semiclassical bulk states, the expectation value of the bulk stress-energy tensor appears as a source in the linearized equations. In particular, the CFT first law leads to Newton's Law of gravitation and the fact that all sources of stress-energy source the gravitational field. In our derivation, this universality of gravity comes directly from the universality of entanglement (the fact that all degrees of freedom in a subsystem contribute to entanglement entropy).
Quantal Definition of the Weak Equivalence Principle
Abel Camacho; Arturo Camacho-Guardian
2008-11-03T23:59:59.000Z
The present work analyzes the meaning of the Weak Equivalence Principle in the context of quantum mechanics. A quantal definition for this principle is introduced. This definition does not require the concept of trajectory and relies upon the phase shift induced by a gravitational field in the context of a quantum interference experiment of two coherent beams of particles. In other words, it resorts to wave properties of the system and not to classical concepts as the idea of trajectory.
Thermodynamics of topological black holes in $R^{2}$ gravity
Cognola, Guido; Vanzo, Luciano; Zerbini, Sergio
2015-01-01T23:59:59.000Z
We study topological black hole solutions of the simplest quadratic gravity action and we find that two classes are allowed. The first is asymptotically flat and mimics the Reissner-Nordstr\\"om solution, while the second is asymptotically de Sitter or anti-de Sitter. In both classes, the geometry of the horizon can be spherical, toroidal or hyperbolic. We focus in particular on the thermodynamical properties of the asymptotically anti-de Sitter solutions and we compute the entropy and the internal energy with Euclidean methods. We find that the entropy is positive-definite for all horizon geometries and this allows to formulate a consistent generalized first law of black hole thermodynamics, which keeps in account the presence of two arbitrary parameters in the solution. The two-dimensional thermodynamical state space is fully characterized by the underlying scale invariance of the action and it has the structure of a projective space. We find a kind of duality between black holes and other objects with the s...
Gravity and Anti-gravity of Fermions: the Unification of Dark Matter and Dark Energy
Chen, X S
2005-01-01T23:59:59.000Z
Massive gravity with second and fourth derivatives is shown to give both attractive and repulsive gravity between fermions. In contrast to the attractive gravity correlated with energy-momentum tensor, the repulsive gravity is proportional to the graviton mass. Therefore, weakly interacting fermions with energy smaller than the graviton mass are both dark matter and dark energy: Their overall gravity is attractive with normal matter but repulsive among themselves. Detailed analyses reveal that this unified dark scenario can properly account for the observed dark matter/energy phenomena: galaxy rotation curves, transition from early cosmic deceleration to recent acceleration; and naturally overcome other dark scenarios' difficulties: the substructure and cuspy core problems, the difference of dark halo distributions in galaxies and clusters, and the cosmic coincidence.
A Kinetic Theory Approach to Quantum Gravity
B. L. Hu
2002-04-22T23:59:59.000Z
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).
Imprint of modified Einstein's gravity on white dwarfs: Unifying type Ia supernovae
Das, Upasana
2015-01-01T23:59:59.000Z
We establish the importance of modified Einstein's gravity (MG) in white dwarfs (WDs) for the first time in the literature. We show that MG leads to significantly sub- and super-Chandrasekhar limiting mass WDs, depending on a single model parameter. However, conventional WDs on approaching Chandrasekhar's limit are expected to trigger type Ia supernovae (SNeIa), a key to unravel the evolutionary history of the universe. Nevertheless, observations of several peculiar, under- and over-luminous SNeIa argue for the limiting mass widely different from Chandrasekhar's limit. Explosions of MG induced sub- and super-Chandrasekhar limiting mass WDs explain under- and over-luminous SNeIa respectively, thus unifying these two apparently disjoint sub-classes. Our discovery questions both the global validity of Einstein's gravity and the uniqueness of Chandrasekhar's limit.
Quantum key distribution with finite resources: Secret key rates via Renyi entropies
Abruzzo, Silvestre; Kampermann, Hermann; Mertz, Markus; Bruss, Dagmar [Institute for Theoretical Physics III, Heinrich-Heine-universitaet Duesseldorf, D-40225 Duesseldorf (Germany)
2011-09-15T23:59:59.000Z
A realistic quantum key distribution (QKD) protocol necessarily deals with finite resources, such as the number of signals exchanged by the two parties. We derive a bound on the secret key rate which is expressed as an optimization problem over Renyi entropies. Under the assumption of collective attacks by an eavesdropper, a computable estimate of our bound for the six-state protocol is provided. This bound leads to improved key rates in comparison to previous results.
Reference-frame-independent quantum key distribution
Laing, Anthony; Rarity, John G.; O'Brien, Jeremy L. [Centre for Quantum Photonics, H. H. Wills Physics Laboratory and Department of Electrical and Electronic Engineering, University of Bristol, BS8 1UB (United Kingdom); Scarani, Valerio [Centre for Quantum Technologies and Department of Physics, National University of Singapore (Singapore)
2010-07-15T23:59:59.000Z
We describe a quantum key distribution protocol based on pairs of entangled qubits that generates a secure key between two partners in an environment of unknown and slowly varying reference frame. A direction of particle delivery is required, but the phases between the computational basis states need not be known or fixed. The protocol can simplify the operation of existing setups and has immediate applications to emerging scenarios such as earth-to-satellite links and the use of integrated photonic waveguides. We compute the asymptotic secret key rate for a two-qubit source, which coincides with the rate of the six-state protocol for white noise. We give the generalization of the protocol to higher-dimensional systems and detail a scheme for physical implementation in the three-dimensional qutrit case.
Luongo, Orlando
2015-01-01T23:59:59.000Z
The existence of current-time universe's acceleration is usually modeled by means of two main strategies. The first makes use of a dark energy barotropic fluid entering \\emph{by hand} the energy-momentum tensor of Einstein's theory. The second lies on extending the Hilbert-Einstein action giving rise to the class of extended theories of gravity. In this work, we propose a third approach, derived as an intrinsic geometrical effect of space-time, which provides repulsive regions under certain circumstances. We demonstrate that the effects of repulsive gravity naturally emerge in the field of a homogeneous and isotropic universe. To this end, we use an invariant definition of repulsive gravity based upon the behavior of the curvature eigenvalues. Moreover, we show that repulsive gravity counterbalances the standard gravitational attraction influencing both late and early times of the universe evolution. This phenomenon leads to the present speed up and to the fast expansion due to the inflationary epoch. In so d...
Public key infrastructure for DOE security research
Aiken, R.; Foster, I.; Johnston, W.E. [and others
1997-06-01T23:59:59.000Z
This document summarizes the Department of Energy`s Second Joint Energy Research/Defence Programs Security Research Workshop. The workshop, built on the results of the first Joint Workshop which reviewed security requirements represented in a range of mission-critical ER and DP applications, discussed commonalties and differences in ER/DP requirements and approaches, and identified an integrated common set of security research priorities. One significant conclusion of the first workshop was that progress in a broad spectrum of DOE-relevant security problems and applications could best be addressed through public-key cryptography based systems, and therefore depended upon the existence of a robust, broadly deployed public-key infrastructure. Hence, public-key infrastructure ({open_quotes}PKI{close_quotes}) was adopted as a primary focus for the second workshop. The Second Joint Workshop covered a range of DOE security research and deployment efforts, as well as summaries of the state of the art in various areas relating to public-key technologies. Key findings were that a broad range of DOE applications can benefit from security architectures and technologies built on a robust, flexible, widely deployed public-key infrastructure; that there exists a collection of specific requirements for missing or undeveloped PKI functionality, together with a preliminary assessment of how these requirements can be met; that, while commercial developments can be expected to provide many relevant security technologies, there are important capabilities that commercial developments will not address, due to the unique scale, performance, diversity, distributed nature, and sensitivity of DOE applications; that DOE should encourage and support research activities intended to increase understanding of security technology requirements, and to develop critical components not forthcoming from other sources in a timely manner.
Sylvia Bratzik; Silvestre Abruzzo; Hermann Kampermann; Dagmar Bruß
2013-03-14T23:59:59.000Z
We investigate quantum repeaters in the context of quantum key distribution. We optimize the secret key rate per memory per second with respect to different distillation protocols and distillation strategies. For this purpose, we also derive an analytical expression for the average number of entangled pairs created by the quantum repeater, including classical communication times for entanglement swapping and entanglement distillation. We investigate the impact of this classical communication time on the secret key rate. We finally study the effect of the detector efficiency on the secret key rate.
Rigorous and General Definition of Thermodynamic Entropy
Gian Paolo Beretta; Enzo Zanchini
2010-10-05T23:59:59.000Z
The physical foundations of a variety of emerging technologies --- ranging from the applications of quantum entanglement in quantum information to the applications of nonequilibrium bulk and interface phenomena in microfluidics, biology, materials science, energy engineering, etc. --- require understanding thermodynamic entropy beyond the equilibrium realm of its traditional definition. This paper presents a rigorous logical scheme that provides a generalized definition of entropy free of the usual unnecessary assumptions which constrain the theory to the equilibrium domain. The scheme is based on carefully worded operative definitions for all the fundamental concepts employed, including those of system, property, state, isolated system, environment, process, separable system, system uncorrelated from its environment, and parameters of a system. The treatment considers also systems with movable internal walls and/or semipermeable walls, with chemical reactions and/or external force fields, and with small numbers of particles. The definition of reversible process is revised by introducing the new concept of scenario. The definition of entropy involves neither the concept of heat nor that of quasistatic process; it applies to both equilibrium and nonequilibrium states. The role of correlations on the domain of definition and on the additivity of energy and entropy is discussed: it is proved that energy is defined and additive for all separable systems, while entropy is defined and additive only for separable systems uncorrelated from their environment; decorrelation entropy is defined. The definitions of energy and entropy are extended rigorously to open systems. Finally, to complete the discussion, the existence of the fundamental relation for stable equilibrium states is proved, in our context, for both closed and open systems.
On the Security of Public Key Protocols
Danny Dolev; et al.
1983-01-01T23:59:59.000Z
Recently the use of public key encryption to provide secure network communication has received considerable attention. Such public key systems are usually effective against passive eavesdroppers, who merely tap the lines and try to decipher the message. It has been pointed out, however, that an improperly designed protocol could be vulnerable to an active saboteur, one who may impersonate another user or alter the message being transmitted. Several models are formulated in which the security of protocols can be discussed precisely. Algorithms and characteri-zations that can be used to determine protocol security in these models are given.
Key Renewable Energy Opportunities for Oklahoma Tribes
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report: I11IG002RTC3WASTE-TO-ENERGY:KenKeriKey IssuesKEY
Gravity as Quantum Foam In-Flow
Cahill, R T
2003-01-01T23:59:59.000Z
The new information-theoretic Process Physics provides an explanation of space as a quantum foam system in which gravity is an inhomogeneous flow of the quantum foam into matter. The older Newtonian and General Relativity theories for gravity are analysed. It is shown that Newtonian gravity may be written in the form of an in-flow. General Relativity is also analysed as an in-flow, for those cases where it has been tested. An analysis of various experimental data demonstrates that absolute motion relative to space has been observed by Michelson and Morley, Miller, Illingworth, Jaseja et al, Torr and Kolen, and by DeWitte. The Dayton Miller and Roland DeWitte data also reveal the in-flow of space into matter which manifests as gravity. The experimental data suggests that the in-flow is turbulent, which amounts to the observation of a gravitational wave phenomena. A new in-flow theory of gravity is proposed which passes all the tests that General Relativity was claimed to have passed, but as well the new theory...
Paliouras, George
of resource management (use case and demand side) and event processing (technology and supply side). MethodsPottebaum et al. Event Definition for Intelligent Resource Management Event Definition for the Application of Event Processing to Intelligent Resource Management Jens Pottebaum University of Paderborn, C
Solar System Constraints on Disformal Gravity Theories
Hiu Yan Ip; Jeremy Sakstein; Fabian Schmidt
2015-07-02T23:59:59.000Z
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.
Quantum gravity effects in the Kerr spacetime
Reuter, M. [Institute of Physics, University of Mainz, Staudingerweg 7, D-55099 Mainz (Germany); Tuiran, E. [Departamento de Fisica, Universidad del Norte, Km 5 via a Puerto Colombia, AA-1569 Barranquilla (Colombia)
2011-02-15T23:59:59.000Z
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.
Holographic Superconductors in Quasi-topological Gravity
Xiao-Mei Kuang; Wei-Jia Li; Yi Ling
2010-12-05T23:59:59.000Z
In this paper we study (3+1) dimensional holographic superconductors in quasi-topological gravity which is recently proposed by R. Myers {\\it et.al.}. Through both analytical and numerical analysis, we find in general the condensation becomes harder with the increase of coupling parameters of higher curvature terms. In particular, comparing with those in ordinary Gauss-Bonnet gravity, we find that positive cubic corrections in quasi-topological gravity suppress the condensation while negative cubic terms make it easier. We also calculate the conductivity numerically for various coupling parameters. It turns out that the universal relation of $\\omega_g/T_c\\simeq 8$ is unstable and this ratio becomes larger with the increase of the coupling parameters. A brief discussion on the condensation from the CFT side is also presented.
Solar system constraints on alternative gravity theories
Sumanta Chakraborty; Soumitra Sengupta
2014-01-14T23:59:59.000Z
The perihelion precession of planetary orbits and the bending angle of null geodesics are estimated for different gravity theories in string-inspired models. It is shown that, for dilaton coupled gravity, the leading order measure in the angle of bending of light comes purely from vacuum expectation value of the dilaton field which may be interpreted as an indicator of a dominant stringy effect over the curvature effect. We arrive at similar results for spherically symmetric solution in quadratic gravity. We also present the perihelion shift and bending of light in the Einstein-Maxwell-Gauss-Bonnet theory with special reference to the Casimir effect and Damour-Polyakov mechanism. Numerical bounds to different coupling parameters in these models are estimated.
Gauge theory of gravity and supergravity
Kaul, Romesh K. [Institute of Mathematical Sciences, Chennai 600 113 (India)
2006-03-15T23:59:59.000Z
We present a formulation of gravity in terms of a theory based on complex SU(2) gauge fields with a general coordinate invariant action functional quadratic in the field strength. Self-duality or anti-self-duality of the field strength emerges as a constraint from the equations of motion of this theory. This in turn leads to Einstein gravity equations for a dilaton and an axion conformally coupled to gravity for the self-dual constraint. The analysis has also been extended to N=1 and 2 super Yang-Mills theory of complex SU(2) gauge fields. This leads to, besides other equations of motion, self-duality/anti-self-duality of generalized supercovariant field strengths. The self-dual case is then shown to yield as its solutions N=1, 2 supergravity equations, respectively.
Solar System Constraints on Disformal Gravity Theories
Ip, Hiu Yan; Schmidt, Fabian
2015-01-01T23:59:59.000Z
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.
Entropic force, noncommutative gravity, and ungravity
Nicolini, Piero [Frankfurt Institute for Advanced Studies (FIAS), Institut fuer Theoretische Physik, Johann Wolfgang Goethe-Universitaet, Ruth-Moufang-Strasse 1, 60438 Frankfurt am Main (Germany)
2010-08-15T23:59:59.000Z
After recalling the basic concepts of gravity as an emergent phenomenon, we analyze the recent derivation of Newton's law in terms of entropic force proposed by Verlinde. By reviewing some points of the procedure, we extend it to the case of a generic quantum gravity entropic correction to get compelling deviations to the Newton's law. More specifically, we study: (1) noncommutative geometry deviations and (2) ungraviton corrections. As a special result in the noncommutative case, we find that the noncommutative character of the manifold would be equivalent to the temperature of a thermodynamic system. Therefore, in analogy to the zero temperature configuration, the description of spacetime in terms of a differential manifold could be obtained only asymptotically. Finally, we extend the Verlinde's derivation to a general case, which includes all possible effects, noncommutativity, ungravity, asymptotically safe gravity, electrostatic energy, and extra dimensions, showing that the procedure is solid versus such modifications.
Emergence in Holographic Scenarios for Gravity
Dieks, Dennis; de Haro, Sebastian
2015-01-01T23:59:59.000Z
'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 ...
An efficient public key infrastructure revocation mechanism
Collins, Tamara Lyn
2000-01-01T23:59:59.000Z
IMPLEMENTATION 35 PKI Structure Key/Certificate Storage in the Repository. PKI User Interface Communication Between Entities. User Interface to RA Communication . . RA to CA Communication CA to Repository Communication. User Interface to Repository... Communication. . . . 42 11 CA to Certificate Repository Communication. . . 43 12 User Interface to Certificate Repository Communication. . . . . . . 44 13 Certificate Creation Process. . . 46 14 Certificate Revocation Process. . 48 15 Certificate Retrieval...
2 Key Achievements 7 Greenhouse Gas Reduction
Princeton University Reports Contents 2 Key Achievements 7 Greenhouse Gas Reduction Campus Energy was established in 2008, the University has invested $5.3 million in energy-savings projects, resulting in annual of a 5.2-megawatt solar collector field. Â· Audit the remaining 20 of the top 50 energy- consuming
Roadmap for selected key measurements of LHCb
The LHCb Collaboration; B. Adeva; M. Adinolfi; A. Affolder; Z. Ajaltouni; J. Albrecht; F. Alessio; M. Alexander; P. Alvarez Cartelle; A. A. Alves Jr; S. Amato; Y. Amhis; J. Amoraal; J. Anderson; O. Aquines Gutierrez; L. Arrabito; M. Artuso; E. Aslanides; G. Auriemma; S. Bachmann; Y. Bagaturia; D. S. Bailey; V. Balagura; W. Baldini; MdC. Barandela Pazos; R. J. Barlow; S. Barsuk; A. Bates; C. Bauer; Th. Bauer; A. Bay; I. Bediaga; K. Belous; I. Belyaev; M. Benayoun; G. Bencivenni; R. Bernet; M. -O. Bettler; A. Bizzeti; T. Blake; F. Blanc; C. Blanks; J. Blouw; S. Blusk; A. Bobrov; V. Bocci; A. Bondar; N. Bondar; W. Bonivento; S. Borghi; A. Borgia; E. Bos; T. J. V. Bowcock; C. Bozzi; J. Bressieux; S. Brisbane; M. Britsch; N. H. Brook; H. Brown; A. Büchler-Germann; J. Buytaert; J. -P. Cachemiche; S. Cadeddu; J. M. Caicedo Carvajal; O. Callot; M. Calvi; M. Calvo Gomez; A. Camboni; W. Cameron; P. Campana; A. Carbone; G. Carboni; A. Cardini; L. Carson; K. Carvalho Akiba; G. Casse; M. Cattaneo; M. Charles; Ph. Charpentier; A. Chlopik; P. Ciambrone; X. Cid Vidal; P. J. Clark; P. E. L. Clarke; M. Clemencic; H. V. Cliff; J. Closier; C. Coca; V. Coco; J. Cogan; P. Collins; F. Constantin; G. Conti; A. Contu; G. Corti; G. A. Cowan; B. D'Almagne; C. D'Ambrosio; D. G. d'Enterria; W. Da Silva; P. David; I. De Bonis; S. De Capua; M. De Cian; F. De Lorenzi; J. M. De Miranda; L. De Paula; P. De Simone; H. De Vries; D. Decamp; H. Degaudenzi; M. Deissenroth; L. Del Buono; C. Deplano; O. Deschamps; F. Dettori; J. Dickens; H. Dijkstra; M. Dima; S. Donleavy; A. C. dos Reis; A. Dovbnya; T. Du Pree; P. -Y. Duval; L. Dwyer; R. Dzhelyadin; C. Eames; S. Easo; U. Egede; V. Egorychev; F. Eisele; S. Eisenhardt; L. Eklund; D. Esperante Pereira; L. Estève; S. Eydelman; E. Fanchini; C. Färber; G. Fardell; C. Farinelli; S. Farry; V. Fave; V. Fernandez Albor; M. Ferro-Luzzi; S. Filippov; C. Fitzpatrick; F. Fontanelli; R. Forty; M. Frank; C. Frei; M. Frosini; J. L. Fungueirino Pazos; S. Furcas; A. Gallas Torreira; D. Galli; M. Gandelman; Y. Gao; J-C. Garnier; L. Garrido; C. Gaspar; N. Gauvin; M. Gersabeck; T. Gershon; Ph. Ghez; V. Gibson; Yu. Gilitsky; V. V. Gligorov; C. Göbel; D. Golubkov; A. Golutvin; A. Gomes; M. Grabalosa Gándara; R. Graciani Diaz; L. A. Granado Cardoso; E. Graugés; G. Graziani; A. Grecu; G. Guerrer; E. Gushchin; Yu. Guz; Z. Guzik; T. Gys; F. Hachon; G. Haefeli; S. C. Haines; T. Hampson; S. Hansmann-Menzemer; R. Harji; N. Harnew; P. F. Harrison; J. He; K. Hennessy; P. Henrard; J. A. Hernando Morata; A. Hicheur; E. Hicks; W. Hofmann; K. Holubyev; P. Hopchev; W. Hulsbergen; P. Hunt; T. Huse; R. S. Huston; D. Hutchcroft; V. Iakovenko; C. Iglesias Escudero; J. Imong; R. Jacobsson; M. Jahjah Hussein; E. Jans; F. Jansen; P. Jaton; B. Jean-Marie; M. John; C. R. Jones; B. Jost; F. Kapusta; T. M. Karbach; J. Keaveney; U. Kerzel; T. Ketel; A. Keune; S. Khalil; B. Khanji; Y. M. Kim; M. Knecht; J. Knopf; S. Koblitz; A. Konoplyannikov; P. Koppenburg; I. Korolko; A. Kozlinskiy; M. Krasowski; L. Kravchuk; P. Krokovny; K. Kruzelecki; M. Kucharczyk; I. Kudryashov; T. Kvaratskheliya; D. Lacarrere; A. Lai; R. W. Lambert; G. Lanfranchi; C. Langenbruch; T. Latham; R. Le Gac; R. Lefevre; A. Leflat; J. Lefrançois; O. Leroy; K. Lessnoff; L. Li; Y. Y. Li; J. Libby; M. Lieng; R. Lindner; S. Lindsey; C. Linn; B. Liu; G. Liu; J. H. Lopes; E. Lopez Asamar; J. Luisier; F. Machefert; I. Machikhiliyan; F. Maciuc; O. Maev; J. Magnin; A. Maier; R. M. D. Mamunur; G. Manca; G. Mancinelli; N. Mangiafave; U. Marconi; F. Marin; J. Marks; G. Martellotti; A. Martens; L. Martin; D. Martinez Santos; Z. Mathe; C. Matteuzzi; V. Matveev; A. Mazurov; G. McGregor; B. Mcharek; C. Mclean; R. McNulty; M. Merk; J. Merkel; M. Merkin; R. Messi; F. C. D. Metlica; J. Michalowski; S. Miglioranzi; M. -N. Minard; S. Monteil; D. Moran; J. V. Morris; R. Mountain; I. Mous; F. Muheim; R. Muresan; F. Murtas; B. Muryn; M. Musy; J. Mylroie-Smith; P. Naik; T. Nakada; R. Nandakumar; J. Nardulli; Z. Natkaniec; M. Nedos; M. Needham; N. Neufeld; L. Nicolas; S. Nies; V. Niess; N. Nikitin; A. Noor; A. Oblakowska-Mucha; V. Obraztsov; S. Oggero; O. Okhrimenko; R. Oldeman; M. Orlandea; A. Ostankov; J. Palacios; M. Palutan; J. Panman; A. Papadelis; A. Papanestis; M. Pappagallo; C. Parkes; G. Passaleva; G. D. Patel; M. Patel; S. K. Paterson; G. N. Patrick; E. Pauna; C. Pauna; C. Pavel; A. Pazos Alvarez; A. Pellegrino; G. Penso; M. Pepe Altarelli; S. Perazzini; D. L. Perego; A. Pérez-Calero Yzquierdo; E. Perez Trigo; P. Perret; G. Pessina; A. Petrella; A. Petrolini; B. Pietrzyk; D. Pinci; S. Playfer; M. Plo Casasus; G. Polok; A. Poluektov; E. Polycarpo; D. Popov; B. Popovici; S. Poss; C. Potterat; A. Powell; S. Pozzi; V. Pugatch; A. Puig Navarro; W. Qian; J. H. Rademacker; B. Rakotomiaramanana; I. Raniuk; G. Raven; S. Redford; W. Reece
2010-11-23T23:59:59.000Z
Six of the key physics measurements that will be made by the LHCb experiment, concerning CP asymmetries and rare B decays, are discussed in detail. The "road map" towards the precision measurements is presented, including the use of control channels and other techniques to understand the performance of the detector with the first data from the LHC.
Key Management Challenges in Smart Grid
Sheldon, Frederick T [ORNL] [ORNL; Duren, Mike [Sypris Electronics, LLC] [Sypris Electronics, LLC
2012-01-01T23:59:59.000Z
Agenda Awarded in February 2011 Team of industry and research organizations Project Objectives Address difficult issues Complexity Diversity of systems Scale Longevity of solution Participate in standards efforts and working groups Develop innovative key management solutions Modeling and simulation ORNL Cyber Security Econometric Enterprise System Demonstrate effectiveness of solution Demonstrate scalability
CHEMICAL ABBREVIATION KEY ABBREVIATION CHEMICAL NAME HAZARDS
Pawlowski, Wojtek
Corrosive - base LiCl Lithium chloride Harmful MeOH Methanol Flammable #12;CHEMICAL ABBREVIATION KEY Irritant destain Methanol,acetic acid,H2O Flammable, Corrosive - acid DI H2O Deionized water DCM FeCl3 Iron(III) chloride Corrosive - acid FeSO4 Iron(II) sulfate Toxic H2O Water HCl Hydrochloric
BACK TO BASICS: YOUR KEYS TO SAFE
Kirschner, Denise
BACK TO BASICS: YOUR KEYS TO SAFE DRIVING BUCKLE UP! Seat belts should never have time off DRIVE the back seat to the front seat.4 ·The back is the best place for pets. According to AAA, similar. Never place the shoulder portion under your arm or behind your back! ·Drivers should sit with at least
Rangeland ecology: Key global research issues & questions
1 Rangeland ecology: Key global research issues & questions Robin Reid and Maria Fernandez-Gimenez This paper discusses developments in our understanding about rangeland ecology and rangeland dynamics in the last 20 years. Before the late 1980's, the mainstream view in range ecology was that livestock
Rangeland ecology: Key global research issues & questions
1 Rangeland ecology: Key global research issues & questions Robin Reid1 and Maria Fernandez Ecology Lab 2Associate Professor Colorado State University, Fort Collins, Colorado, USA Global Issues and Questions in Rangeland Ecology · Despite the focus here on global issues, we need to recognize that Mongolia
Key facts about Argonne National Laboratory
Kemner, Ken
Key facts about Argonne National Laboratory Argonne National Laboratory occupies 1,500 wooded acres in southeast DuPage County near Chicago. Mission Argonne's mission is to apply a unique blend of world needs of our nation. Argonne conducts R&D in many areas of basic and applied science and engineering
www.defra.gov.uk Environmental Key
;Environmental Key Performance Indicators Reporting Guidelines for UK Business #12;Department for Environment with the Crown. This publication (excluding the logo) may be reproduced free of charge in any format or medium they operate in, and their impact on the environment, are most likely to prosper in the long-term. At the same
Theoretical and experimental study of nonlinear internal gravity wave beams
Tabaei Befrouei, Ali, 1974-
2005-01-01T23:59:59.000Z
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 ...
Chemical and Petroleum Engineering Key and Lab Space Agreement
Calgary, University of
Chemical and Petroleum Engineering Key and Lab Space Agreement Key Holder Information Last Name and Petroleum Engineering remain the property of the Department. I agree to pay a deposit for the keys/Graduate Student Study space that has been assigned. Keys Any keys issued to me from the Department of Chemical
Exact solutions of three dimensional black holes: Einstein gravity vs F(R) gravity
S. H. Hendi; B. Eslam Panah; R. Saffari
2014-10-28T23:59:59.000Z
In this paper, we consider Einstein gravity in the presence of a class of nonlinear electrodynamics, called power Maxwell invariant (PMI). We take into account $(2+1)$-dimensional spacetime in Einstein-PMI gravity and obtain its black hole solutions. Then, we regard pure $F(R)$ gravity as well as $F(R)$-conformally invariant Maxwell theory to obtain exact solutions of the field equations with black hole interpretation. Finally, we investigate the conserved and thermodynamic quantities and discuss about the first law of thermodynamics for the mentioned gravitational models.
Testing a Dilaton Gravity Model using Nucleosynthesis
Sibel Boran; Emre Onur Kahya
2014-09-05T23:59:59.000Z
Big Bang Nucleosynthesis (BBN) offers one of the most strict evidences for the Lambda-CDM cosmology at present, as well as the Cosmic Microwave Background (CMB) radiation. In this work, our main aim is to present the outcomes of our calculations related to primordial abundances of light elements, in the context of higher dimensional steady-state universe model in the dilaton gravity. Our results show that abundances of light elements (primordial D, 3He, 4He, T, 7Li) are significantly different for some cases, and a comparison is given between a particular dilaton gravity model and Lambda-CDM in the light of the astrophysical observations.
Energy Distribution in f(R) Gravity
M. Sharif; M. Farasat Shamir
2009-12-18T23:59:59.000Z
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.
Multidimensional Gravity on the Principal Bundles
V. D. Dzhunushaliev
1997-11-10T23:59:59.000Z
The multidimensional gravity on the total space of principal bundle is considered. In this theory the gauge fields arise as nondiagonal components of multidimensional metric. The spherically symmetric and cosmology solutions for gravity on SU(2) principal bundle are obtained. The static spherically symmetric solution is wormhole-like solution located between two null surfaces, in contrast to 4D Einstein-Yang-Mills theory where corresponding solution (black hole) located outside of event horizon. Cosmology solution (at least locally) has the bouncing off effect for spatial dimensions. In spirit of Einstein these solutions are vacuum solutions without matter.
Violation of Energy Bounds in Designer Gravity
Thomas Hertog
2006-07-31T23:59:59.000Z
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.
Weak Gravity Conjecture for Noncommutative Field Theory
Qing-Guo Huang; Jian-Huang She
2006-11-20T23:59:59.000Z
We investigate the weak gravity bounds on the U(1) gauge theory and scalar field theories in various dimensional noncommutative space. Many results are obtained, such as the upper bound on the noncommutative scale $g_{YM}M_p$ for four dimensional noncommutative U(1) gauge theory. We also discuss the weak gravity bounds on their commutative counterparts. For example, our result on 4 dimensional noncommutative U(1) gauge theory reduces in certain limit to its commutative counterpart suggested by Arkani-Hamed et.al at least at tree-level.
Holographic superconductors from the massive gravity
Hua Bi Zeng; Jian-Pin Wu
2014-09-24T23:59:59.000Z
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.
One Loop Beta Functions in Topologically Massive Gravity
R. Percacci; E. Sezgin
2010-02-15T23:59:59.000Z
We calculate the running of the three coupling constants in cosmological, topologically massive 3d gravity. We find that \
2014 Manufacturing Energy and Carbon Footprints: Definitions...
Broader source: Energy.gov (indexed) [DOE]
and Assumptions A number of key terms are used to interpret the manufacturing energy and carbon footprints. The terms associated with the energy footprint analysis are...
HoravaLifshitz gravity Victoria University of Wellington
Visser, Matt
Abstract HoravaÂLifshitz gravity Victoria University of Wellington Te Whare WÂ¯ananga o te Â¯Upoko o Vancouver Tuesday 25 August 2009 Matt Visser Who's afraid of Lorentz symmetry breaking? #12;Abstract HoravaÂLifshitz gravity HoravaÂLifshitz gravity: As of 23 August 2009 Spires reports that this topic has generated: 3
Nordstrom's scalar theory of gravity and the equivalence principle
Nathalie Deruelle
2011-04-24T23:59:59.000Z
Nordstrom's theory of gravity, which describes gravity by a scalar field in flat spacetime, is observationally ruled out. It is however the only theory of gravity with General Relativity to obey the strong equivalence principle. I show in this paper that this remarkable property is true beyond post-newtonian level and can be related to the existence of a 'Nordstrom-Katz' superpotential.
Observing ocean heat content using satellite gravity and altimetry
Jayne, Steven
: ocean heat content, altimetry, satellite gravity, steric height, remote sensing Citation: Jayne, S. RObserving ocean heat content using satellite gravity and altimetry Steven R. Jayne1,2 and John M with satellite measurements of the Earth's time-varying gravity to give improved estimates of the ocean's heat
Conformal gravity from the AdS/CFT mechanism
Aros, Rodrigo; Romo, Mauricio; Zamorano, Nelson [Departamento de Ciencias Fisicas, Universidad Andres Bello, Av. Republica 252, Santiago (Chile); Departamento de Fisica, Facultad de Ciencias Fisicas y Matematicas, Universidad de Chile, Avda Blanco Encalada 2008, Santiago (Chile)
2007-03-15T23:59:59.000Z
We explicitly calculate the induced gravity theory at the boundary of an asymptotically anti-de Sitter five dimensional Einstein gravity. We also display the action that encodes the dynamics of radial diffeomorphisms. It is found that the induced theory is a four dimensional conformal gravity plus a scalar field. This calculation confirms some previous results found by a different approach.
Quantum Gravity in Three Dimensions from Higher-Spin Holography
Tan, Hai Siong
2013-01-01T23:59:59.000Z
Higher Spin Anti-de Sitter Gravity,” JHEP 1012, 007 (2010)gravity in three dimensions from the per- spective of higher-spin holography in anti-gravity in three dimen- sions in the framework of higher-spin holography in anti-
The Mars Gravity Biosatellite as an innovative partial gravity research platform
Fulford-Jones, Thaddeus R. F
2008-01-01T23:59:59.000Z
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 ...
Webb, Spahr C.
, Petrologic and Seismic Expedition (GLIMPSE) study area from seismic refraction data R. Chadwick Holmes,1, Intraplate Melting, Petrologic and Seismic Expedition (GLIMPSE) experiment investigated the velocity in the Gravity Lineations, Intraplate Melting, Petrologic and Seismic Expedition (GLIMPSE) study area from
Three key elements necessary for successful testing
Ehlig-Economides, C.A.; Hegeman, P. (Schlumberger Oilfield Services, Houston, TX (United States)); Clark, G. (Schlumberger Oilfield Services, Aberdeen (United Kingdom))
1994-07-25T23:59:59.000Z
Real-time surface readout during data acquisition, downhole shutting, and appropriate pressure gauges are three key elements for successful well tests. These elements are often overlooked in designing and implementing a successful well test. This second in a series of three articles on well testing shows how these elements affected the testing of an example well. Also reviewed are the capabilities of several new testing tools and techniques.
Key Physical Mechanisms in Nanostructured Solar Cells
Dr Stephan Bremner
2010-07-21T23:59:59.000Z
The objective of the project was to study both theoretically and experimentally the excitation, recombination and transport properties required for nanostructured solar cells to deliver energy conversion efficiencies well in excess of conventional limits. These objectives were met by concentrating on three key areas, namely, investigation of physical mechanisms present in nanostructured solar cells, characterization of loss mechanisms in nanostructured solar cells and determining the properties required of nanostructured solar cells in order to achieve high efficiency and the design implications.
Infrared fixed point in quantum Einstein gravity
S. Nagy; J. Krizsan; K. Sailer
2012-06-28T23:59:59.000Z
We performed the renormalization group analysis of the quantum Einstein gravity in the deep infrared regime for different types of extensions of the model. It is shown that an attractive infrared point exists in the broken symmetric phase of the model. It is also shown that due to the Gaussian fixed point the IR critical exponent $\
A New Model of Nonlocal Modified Gravity
Ivan Dimitrijevic; Branko Dragovich; Jelena Grujic; Zoran Rakic
2014-11-18T23:59:59.000Z
We consider a new modified gravity model with nonlocal term of the form $R^{-1} \\mathcal{F}(\\Box) R. $ This kind of nonlocality is motivated by investigation of applicability of a few unusual ans\\"atze to obtain some exact cosmological solutions. In particular, we find attractive and useful quadratic ansatz $\\Box R = q R^{2}.$
Ultrasonic hydrometer. [Specific gravity of electrolyte
Swoboda, C.A.
1982-03-09T23:59:59.000Z
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.
Topological Black Holes in Quantum Gravity
J. Kowalski-Glikman; D. Nowak-Szczepaniak
2000-07-31T23:59:59.000Z
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.
Schwarzschild solution in extended teleparallel gravity
Nashed, G G L
2015-01-01T23:59:59.000Z
Tetrad field, with two unknown functions of radial coordinate and an angle $\\Phi$ which is the polar angle $\\phi$ times a function of the redial coordinate, is applied to the field equation of modified theory of gravity. Exact vacuum solution is derived whose scalar torsion, $T ={T^\\alpha}_{\\mu \
Constraining torsion with Gravity Probe B
Mao Yi; Guth, Alan H.; Cabi, Serkan [Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Tegmark, Max [Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); MIT Kavli Institute for Astrophysics and Space Research, Cambridge, Massachusetts 02139 (United States)
2007-11-15T23:59:59.000Z
It is well-entrenched folklore that all torsion gravity theories predict observationally negligible torsion in the solar system, since torsion (if it exists) couples only to the intrinsic spin of elementary particles, not to rotational angular momentum. We argue that this assumption has a logical loophole which can and should be tested experimentally, and consider nonstandard torsion theories in which torsion can be generated by macroscopic rotating objects. In the spirit of action=reaction, if a rotating mass like a planet can generate torsion, then a gyroscope would be expected to feel torsion. An experiment with a gyroscope (without nuclear spin) such as Gravity Probe B (GPB) can test theories where this is the case. Using symmetry arguments, we show that to lowest order, any torsion field around a uniformly rotating spherical mass is determined by seven dimensionless parameters. These parameters effectively generalize the parametrized post-Newtonian formalism and provide a concrete framework for further testing Einstein's general theory of relativity (GR). We construct a parametrized Lagrangian that includes both standard torsion-free GR and Hayashi-Shirafuji maximal torsion gravity as special cases. We demonstrate that classic solar system tests rule out the latter and constrain two observable parameters. We show that Gravity Probe B is an ideal experiment for further constraining nonstandard torsion theories, and work out the most general torsion-induced precession of its gyroscope in terms of our torsion parameters.
Scale invariance, unimodular gravity and dark energy
Mikhail Shaposhnikov; Daniel Zenhausern
2008-12-16T23:59:59.000Z
We demonstrate that the combination of the ideas of unimodular gravity, scale invariance, and the existence of an exactly massless dilaton leads to the evolution of the universe supported by present observations: inflation in the past, followed by the radiation and matter dominated stages and accelerated expansion at present. All mass scales in this type of theories come from one and the same source.
Topology in 4D simplicial quantum gravity
S. Bilke; Z. Burda; B. Petersson
1996-11-22T23:59:59.000Z
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.
Schwarzschild solution in extended teleparallel gravity
G. G. L. Nashed
2015-01-05T23:59:59.000Z
Tetrad field, with two unknown functions of radial coordinate and an angle $\\Phi$ which is the polar angle $\\phi$ times a function of the redial coordinate, is applied to the field equation of modified theory of gravity. Exact vacuum solution is derived whose scalar torsion, $T ={T^\\alpha}_{\\mu \
The diffeomorphism algebra approach to quantum gravity
T. A. Larsson
1999-09-13T23:59:59.000Z
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.
Running Coupling Constants in 2D Gravity
Christof Schmidhuber
1993-08-26T23:59:59.000Z
The renormalization group flow in two--dimensional field theories that are coupled to gravity is discussed at the example of the sine-Gordon model. In order to derive the phase diagram in agreement with the matrix model results, it is necessary to generalize the theory of David, Distler and Kawai.
Explicit versus Spontaneous Diffeomorphism Breaking in Gravity
Robert Bluhm
2015-04-02T23:59:59.000Z
Gravitational theories with fixed background fields break local Lorentz and diffeomorphism invariance either explicitly or spontaneously. In the case of explicit breaking it is known that conflicts can arise between the dynamics and geometrical constraints, while spontaneous breaking evades this problem. It is for this reason that in the gravity sector of the Standard-Model Extension (SME) it is assumed that the background fields (SME coefficients) originate from spontaneous symmetry breaking. However, in other examples, such as Chern-Simons gravity and massive gravity, diffeomorphism invariance is explicitly broken by the background fields, and the potential conflicts between the dynamics and geometry can be avoided in most cases. An analysis of how this occurs is given, and the conditions that are placed on the metric tensor and gravitational structure as a result of the presence of an explicit-breaking background are described. The gravity sector of the SME is then considered for the case of explicit breaking. However, it is found that a useful post-Newtonian limit is only obtained when the symmetry breaking is spontaneous.
Second order noncommutative corrections to gravity
Calmet, Xavier [Universite Libre de Bruxelles, Service de Physique Theorique, CP225 Boulevard du Triomphe (Campus plaine), B-1050 Brussels (Belgium); Kobakhidze, Archil [Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 (United States)
2006-08-15T23:59:59.000Z
In this work, we calculate the leading order corrections to general relativity formulated on a canonical noncommutative spacetime. These corrections appear in the second order of the expansion in theta. First order corrections can only appear in the gravity-matter interactions. Some implications are briefly discussed.
Building America Expert Meeting: Key Innovations for Adding Energy...
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Key Innovations for Adding Energy Efficiency to Maintenance Projects Building America Expert Meeting: Key Innovations for Adding Energy Efficiency to Maintenance Projects This...
authenticated key exchange: Topics by E-print Network
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desirable attributes. Index Terms--Mutual Authentication; Key Management; SRP; Security; Smart Meter; Smart Leung, Victor C.M. 56 Authentication and Key Agreement via Memorable...
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Temperature(C) 200 2 Finite key analysis for symmetric attacks in quantum key distribution Quantum Physics (arXiv) Summary: We introduce a constructive method to calculate...
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Cooling Towers: Understanding Key Components of Cooling Towers and How to Improve Water Efficiency Cooling Towers: Understanding Key Components of Cooling Towers and How to Improve...
Midstream Infrastructure Improvements Key to Realizing Full Potential...
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Midstream Infrastructure Improvements Key to Realizing Full Potential of Domestic Natural Gas Midstream Infrastructure Improvements Key to Realizing Full Potential of Domestic...
Measuring the Earth's gravity field with cold atom interferometers
Carraz, Olivier; Massotti, Luca; Haagmans, Roger; Silvestrin, Pierluigi
2015-01-01T23:59:59.000Z
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.
JOINT DEGREE PROGRAMS DEFINITION AND POLICY
Omiecinski, Curtis
1 JOINT DEGREE PROGRAMS DEFINITION AND POLICY: Within the fields of medicine and law, dual training for such complementary training can be demonstrated, the creation of a formal "Joint" degree program in which students or MD) offered at Penn State may be warranted. Such Joint degree programs enhance the educational
Pink Eye Conjunctivitis Definition, Symptoms and Causes
Suzuki, Masatsugu
Pink Eye Â Conjunctivitis Definition, Symptoms and Causes Pink eye is the common name given to inflammation of the conjunctiva of the eye. It is otherwise called conjunctivitis. The conjunctiva is the transparent membrane that lines the eyelids and covers the whites of the eyes. Very small, superficial blood
Business Practice Manual for Definitions & Acronyms
Tesfatsion, Leigh
Janaury 21, 2011 #12;CAISO Business Practice Manual BPM for Definitions & Acronyms Version 76 Last Revised: March 31, 2009 BPM Owner: Mike Dozier BPM Owner's Title: Senior Counsel Revision History Version Date Description 2 2009-12-18 Incorporating payment acceleration language submitted in BPM PRR 122
Evolutionary Algorithms for Definition Extraction Claudia Borg
Pace, Gordon J.
Evolutionary Algorithms for Definition Extraction Claudia Borg Dept. of I.C.S. University of Malta claudia.borg@um.edu.mt Mike Rosner Dept. of I.C.S. University of Malta mike.rosner@um.edu.mt Gordon Pace Dept. of Computer Science University of Malta gordon.pace@um.edu.mt Abstract Books and other text
The equilibrium of dense plasma in a gravity field
B. V. Vasiliev
2000-10-31T23:59:59.000Z
The equilibrium of dense plasma in a gravity field and problem of a gravity-induced electric polarization in this matter are discussed. The calculation for metals performed before shows that both - the gravity-induced compressive strain and the gravity-induced electric field - are inversely proportional to their Young moduli. The calculation for high dense plasma, where Young modulus is equal to zero, shows that there is another effect: each cell of this plasma inside a celestial body in own gravity field obtains the small positive electric charge. It happens as heavy ions sag on to light electron clouds. A celestial body stays electrically neutral as a whole, because the negative electric charge concentrates on its surface. The gravity-induced positive volume charge is very small, its order of magnitude equals to $10^{-18}e$ per atom only. But it is sufficient for the complete conterbalancing of the gravity force.
Min-entropy and quantum key distribution: Nonzero key rates for ''small'' numbers of signals
Bratzik, Sylvia; Mertz, Markus; Kampermann, Hermann; Bruss, Dagmar [Institute for Theoretical Physics III, Heinrich-Heine-Universitaet Duesseldorf, D-40225 Duesseldorf (Germany)
2011-02-15T23:59:59.000Z
We calculate an achievable secret key rate for quantum key distribution with a finite number of signals by evaluating the quantum conditional min-entropy explicitly. The min-entropy for a classical random variable is the negative logarithm of the maximal value in its probability distribution. The quantum conditional min-entropy can be expressed in terms of the guessing probability, which we calculate for d-dimensional systems. We compare these key rates to previous approaches using the von Neumann entropy and find nonzero key rates for a smaller number of signals. Furthermore, we improve the secret key rates by modifying the parameter estimation step. Both improvements taken together lead to nonzero key rates for only 10{sup 4}-10{sup 5} signals. An interesting conclusion can also be drawn from the additivity of the min-entropy and its relation to the guessing probability: for a set of symmetric tensor product states, the optimal minimum-error discrimination (MED) measurement is the optimal MED measurement on each subsystem.
Vacuum energy in Einstein-Gauss-Bonnet anti-de Sitter gravity
Kofinas, Georgios [Departament de Fisica Fonamental, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain); Olea, Rodrigo [Centro Multidisciplinar de Astrofisica-CENTRA, Departamento de Fisica, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Avenida Rovisco Pais 1, 1049-001 Lisbon (Portugal)
2006-10-15T23:59:59.000Z
A finite action principle for Einstein-Gauss-Bonnet anti-de Sitter gravity is achieved by supplementing the bulk Lagrangian by a suitable boundary term, whose form substantially differs in odd and even dimensions. For even dimensions, this term is given by the boundary contribution in the Euler theorem with a coupling constant fixed, demanding the spacetime to have constant (negative) curvature in the asymptotic region. For odd dimensions, the action is stationary under a boundary condition on the variation of the extrinsic curvature. A well-posed variational principle leads to an appropriate definition of energy and other conserved quantities using the Noether theorem, and to a correct description of black hole thermodynamics. In particular, this procedure assigns a nonzero energy to anti-de Sitter spacetime in all odd dimensions.
Quantum key distribution with entangled photon sources
Xiongfeng Ma; Chi-Hang Fred Fung; Hoi-Kwong Lo
2007-03-14T23:59:59.000Z
A parametric down-conversion (PDC) source can be used as either a triggered single photon source or an entangled photon source in quantum key distribution (QKD). The triggering PDC QKD has already been studied in the literature. On the other hand, a model and a post-processing protocol for the entanglement PDC QKD are still missing. In this paper, we fill in this important gap by proposing such a model and a post-processing protocol for the entanglement PDC QKD. Although the PDC model is proposed to study the entanglement-based QKD, we emphasize that our generic model may also be useful for other non-QKD experiments involving a PDC source. Since an entangled PDC source is a basis independent source, we apply Koashi-Preskill's security analysis to the entanglement PDC QKD. We also investigate the entanglement PDC QKD with two-way classical communications. We find that the recurrence scheme increases the key rate and Gottesman-Lo protocol helps tolerate higher channel losses. By simulating a recent 144km open-air PDC experiment, we compare three implementations -- entanglement PDC QKD, triggering PDC QKD and coherent state QKD. The simulation result suggests that the entanglement PDC QKD can tolerate higher channel losses than the coherent state QKD. The coherent state QKD with decoy states is able to achieve highest key rate in the low and medium-loss regions. By applying Gottesman-Lo two-way post-processing protocol, the entanglement PDC QKD can tolerate up to 70dB combined channel losses (35dB for each channel) provided that the PDC source is placed in between Alice and Bob. After considering statistical fluctuations, the PDC setup can tolerate up to 53dB channel losses.
Bertini, Robert L.
The impacts of congestion on time-definitive urban freight distribution networks CO2 emission Accepted 29 November 2010 Keywords: Vehicle routing Time-dependent travel time speed GHG or CO2 emissions pressures to limit the impacts associated with CO2 emissions are mounting rapidly. A key challenge
Bertini, Robert L.
1 The Impacts of Congestion on Time-definitive Urban Freight Distribution1 Networks CO2 Emission pressures to limit the impacts13 associated with CO2 emissions are mounting rapidly. A key challenge on CO2 emissions are hindered by the complexities of vehicle routing18 problems with time
STGWG Key Outcomes for May 3, 2010
Office of Environmental Management (EM)
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011 Strategic2 OPAM615_CostNSARDevelopmental AssignmentApril 2,OCTOBER 2-3,|Key
STGWG Key Outcomes for October 21, 2009
Office of Environmental Management (EM)
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Key Associados Bradesco JV | Open Energy Information
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Bioenergy Key Publications | Department of Energy
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
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Key Predistribution Techniques for Grid-Based Wireless Sensor Networks
Key Predistribution Techniques for Grid-Based Wireless Sensor Networks Simon R. Blackburn1 , Tuvi sensor networks. Networks consisting of wireless sensor nodes ar- ranged in a grid pattern have many for the instantiation of these schemes. Key words: Key predistribution, wireless sensor networks; symmetric key
Definitional Reflection and the Completion Peter Schroeder-Heister *
Schroeder-Heister, Peter
/11-1, and by Esprit Basic Research Working Group 7232 (GENTZEN). #12;334 which is the completed definition
Manufacturing Energy and Carbon Footprint Definitions and Assumptions...
Broader source: Energy.gov (indexed) [DOE]
More Documents & Publications Understanding Manufacturing Energy and Carbon Footprints, October 2012 2010 Manufacturing Energy and Carbon Footprints: Definitions...
Quantum key distribution with entangled photon sources
Ma, X; Lo, H K; Ma, Xiongfeng; Fung, Chi-Hang Fred; Lo, Hoi-Kwong
2007-01-01T23:59:59.000Z
A parametric down-conversion (PDC) source can be used as either a triggered single photon source or an entangled photon source in quantum key distribution (QKD). The triggering PDC QKD has already been studied in the literature. On the other hand, a model and a post-processing protocol for the entanglement PDC QKD are still missing. In this paper, we fill in this important gap by proposing such a model and a post-processing protocol for the entanglement PDC QKD. Although the PDC model is proposed to study the entanglement-based QKD, we emphasize that our generic model may also be useful for other non-QKD experiments involving a PDC source. Since an entangled PDC source is a basis independent source, we apply Koashi-Preskill's security analysis to the entanglement PDC QKD. We also investigate the entanglement PDC QKD with two-way classical communications. We find that the recurrence scheme increases the key rate and Gottesman-Lo protocol helps tolerate higher channel losses. By simulating a recent 144km open-a...
Michael Rupen EVLA Phase II Definition Aug 23 25, 2001.
Groppi, Christopher
Michael Rupen EVLA Phase II Definition Meeting Aug 23 Â 25, 2001. 1 EVLA Phase II Scientific Overview Michael P. Rupen #12;Michael Rupen EVLA Phase II Definition Meeting Aug 23 Â 25, 2001. 2 New the resolution Â· Always available! #12;Michael Rupen EVLA Phase II Definition Meeting Aug 23 Â 25, 2001. 3 NMA
Formal definition of POTENTIAL ENERGY (valid for conservative forces only)
page - 16 Formal definition of POTENTIAL ENERGY (valid for conservative forces only) Given one type of conservative force F UB - UA= - = - Definition of 'Potential energy difference" conserv #12;page - 17 the definition of the "potential energy difference UB - UA " as equal to negative value of the work W done
Language Definitions as Rewrite Theories Andrei Arusoaie1
Boyer, Edmond
Language Definitions as Rewrite Theories Andrei Arusoaie1 , Dorel Lucanu1 , Vlad Rusu2 , Traian languages. It includes software tools for compiling K language definitions to Maude rewrite theories transformation of language definitions that enables the symbolic execution of programs, i.e., the exe- cution
Definite Descriptions, Focus Shift, and a Theory of Discourse Interpretation
Poesio, Massimo
Definite Descriptions, Focus Shift, and a Theory of Discourse Interpretation Massimo Poesio Centre of situations and their hierarchical organization. 1 Ingredients of a Theory of Definite Description InterÂ pretation A theory of definite description (DD) interpretation must build on a general theory of discourse
NIH WORKING DEFINITION OF BIOINFORMATICS AND COMPUTATIONAL BIOLOGY
Rau, Don C.
NIH WORKING DEFINITION OF BIOINFORMATICS AND COMPUTATIONAL BIOLOGY July 17, 2000 The following working definition of bioinformatics and computational biology were developed by the BISTIC Definition Liu Preamble Bioinformatics and computational biology are rooted in life sciences as well as computer
Poincare gauge theory of gravity: Friedman cosmology with even and odd parity modes: Analytic part
Baekler, Peter; Hehl, Friedrich W.; Nester, James M. [Department of Media, Fachhochschule Duesseldorf, University of Applied Sciences, 40474 Duesseldorf (Germany); Institute for Theoretical Physics, University of Cologne, 50923 Koeln, Germany, and Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211 (United States); Department of Physics, Institute of Astronomy, and Center of Mathematics and Theoretical Physics, National Central University, Chungli 320, Taiwan (China)
2011-01-15T23:59:59.000Z
We propose a cosmological model in the framework of the Poincare gauge theory of gravity (PG). The gravitational Lagrangian is quadratic in both curvature and torsion. In our specific model, the Lagrangian contains (i) the curvature scalar R and the curvature pseudoscalar X linearly and quadratically (including an RX term) and (ii) pieces quadratic in the torsion vector V and the torsion axial vector A (including a VA term). We show generally that in quadratic PG models we have nearly the same number of parity conserving terms ('world') and of parity violating terms ('shadow world'). This offers new perspectives in cosmology for the coupling of gravity to matter and antimatter. Our specific model generalizes the fairly realistic ''torsion cosmologies'' of Shie-Nester-Yo (2008) and Chen et al. (2009). With a Friedman type ansatz for an orthonormal coframe and a Lorentz connection, we derive the two field equations of PG in an explicit form and discuss their general structure in detail. In particular, the second field equation can be reduced to first order ordinary differential equations for the curvature pieces R(t) and X(t). Including these along with certain relations obtained from the first field equation and curvature definitions, we present a first order system of equations suitable for numerical evaluation. This is deferred to the second, numerical part of this paper.
The Definition and Classification of Universes
Bjorken, J.
2004-10-12T23:59:59.000Z
We assume that the concept of a multiverse makes sense, and suggest a specific, standardized definition for member universes which are similar to our own. Central to this description is the definition of size, which is taken to be the asymptotic value, at large times, of the inverse Hubble constant. Thus the cosmological constant plays a central role in defining the properties of the subset of universes similar to our own. We then assume that vacuum parameters and coupling constants of the standard model are dependent upon the size of a universe, and propose a specific form for the dependence. Anthropic considerations then limit the size of habitable universes (as we understand that concept) to be within a factor two of our own. Implications of this picture for understanding the standard-model ''hierarchy problem'' are discussed, as are general issues of falsifiability and/or verifiability of these ideas.
Propagation of gravitational waves in multimetric gravity
Manuel Hohmann
2012-04-22T23:59:59.000Z
We discuss the propagation of gravitational waves in a recently discussed class of theories containing N >= 2 metric tensors and a corresponding number of standard model copies. Using the formalism of gauge-invariant linear perturbation theory we show that all gravitational waves propagate at the speed of light. We then employ the Newman-Penrose formalism to show that two to six polarizations of gravitational waves may exist, depending on the parameters entering the equations of motion. This corresponds to E(2) representations N_2, N_3, III_5 and II_6. We finally apply our general discussion to a recently presented concrete multimetric gravity model and show that it is of class N_2, i.e., it allows only two tensor polarizations, as it is the case for general relativity. Our results provide the theoretical background for tests of multimetric gravity theories using the upcoming gravitational wave experiments.
Hydrogen atom in Palatini theories of gravity
Gonzalo J. Olmo
2008-06-03T23:59:59.000Z
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.
Quantum Gravity models - brief conceptual summary
Jerzy Lukierski
2014-11-27T23:59:59.000Z
After short historical overview we describe the difficulties with application of standard QFT methods in quantum gravity (QG). The incompatibility of QG with the use of classical continuous space-time required conceptually new approach. We present briefly three proposals: loop quantum gravity (LQG), the field-theoretic framework on noncommutative space-time and QG models formulated on discretized (triangularized) space-time. We evaluate these models as realizing expected important properties of QG: background independence, consistent quantum diffeomorphisms, noncommutative or discrete structure of space-time at very short distances, finite/renormalizable QG corrections. We only briefly outline an important issue of embedding QG into larger geometric and dynamical frameworks (e.g. supergravity, (super)strings, p-branes, M-theory), with the aim to achieve full unification of all fundamental interactions.
Holographic studies of quasi-topological gravity
Robert C. Myers; Miguel F. Paulos; Aninda Sinha
2010-06-09T23:59:59.000Z
Quasi-topological gravity is a new gravitational theory including curvature-cubed interactions and for which exact black hole solutions were constructed. In a holographic framework, classical quasi-topological gravity can be thought to be dual to the large $N_c$ limit of some non-supersymmetric but conformal gauge theory. We establish various elements of the AdS/CFT dictionary for this duality. This allows us to infer physical constraints on the couplings in the gravitational theory. Further we use holography to investigate hydrodynamic aspects of the dual gauge theory. In particular, we find that the minimum value of the shear-viscosity-to-entropy-density ratio for this model is $\\eta/s \\simeq 0.4140/(4\\pi)$.
Black holes in Asymptotically Safe Gravity
Saueressig, Frank; D'Odorico, Giulio; Vidotto, Francesca
2015-01-01T23:59:59.000Z
Black holes are among the most fascinating objects populating our universe. Their characteristic features, encompassing spacetime singularities, event horizons, and black hole thermodynamics, provide a rich testing ground for quantum gravity ideas. In this note we observe that the renormalization group improved Schwarzschild black holes constructed by Bonanno and Reuter within Weinberg's asymptotic safety program constitute a prototypical example of a Hayward geometry used to model non-singular black holes within quantum gravity phenomenology. Moreover, they share many features of a Planck star: their effective geometry naturally incorporates the one-loop corrections found in the effective field theory framework, their Kretschmann scalar is bounded, and the black hole singularity is replaced by a regular de Sitter patch. The role of the cosmological constant in the renormalization group improvement process is briefly discussed.
Elliptic Genera and 3d Gravity
Benjamin, Nathan; Kachru, Shamit; Moore, Gregory W; Paquette, Natalie M
2015-01-01T23:59:59.000Z
We describe general constraints on the elliptic genus of a 2d supersymmetric conformal field theory which has a gravity dual with large radius in Planck units. We give examples of theories which do and do not satisfy the bounds we derive, by describing the elliptic genera of symmetric product orbifolds of $K3$, product manifolds, certain simple families of Calabi-Yau hypersurfaces, and symmetric products of the "Monster CFT." We discuss the distinction between theories with supergravity duals and those whose duals have strings at the scale set by the AdS curvature. Under natural assumptions we attempt to quantify the fraction of (2,2) supersymmetric conformal theories which admit a weakly curved gravity description, at large central charge.
Chaotic inflation in higher derivative gravity theories
Myrzakul, Shynaray; Sebastiani, Lorenzo
2015-01-01T23:59:59.000Z
In this paper, we investigate chaotic inflation from scalar field subjected to potential in the framework of $f(R^2, P, Q)$-gravity, where we add a correction to Einstein's gravity based on a function of the square of the Ricci scalar $R^2$, the contraction of the Ricci tensor $P$, and the contraction of the Riemann tensor $Q$. The Gauss-Bonnet case is also discussed. We give the general formalism of inflation, deriving the slow-roll parameters, the $e$-folds number, and the spectral indexes. Several explicit examples are furnished, namely we will consider the cases of massive scalar field and scalar field with quartic potential and some power-law function of the curvature invariants under investigation in the gravitational action of the theory. Viable inflation according with observations is analyzed.
Infrared modification of gravity from conformal symmetry
Gegenberg, Jack; Seahra, Sanjeev S
2015-01-01T23:59:59.000Z
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.
Gauge Freedom and Relativity: A Unified Treatment of Electromagnetism, Gravity and the Dirac Field
Clifford E. Chafin
2015-01-18T23:59:59.000Z
The geometric properties of General Relativity are reconsidered as a particular nonlinear interaction of fields on a flat background where the perceived geometry and coordinates are "physical" entities that are interpolated by a patchwork of observable bodies with a nonintuitive relationship to the underlying fields. This more general notion of gauge in physics opens an important door to put all fields on a similar standing but requires a careful reconsideration of tensors in physics and the conventional wisdom surrounding them. The meaning of the flat background and the induced conserved quantities are discussed and contrasted with the "observable" positive definite energy and probability density in terms of the induced physical coordinates. In this context, the Dirac matrices are promoted to dynamic proto-gravity fields and the keeper of "physical metric" information. Independent sister fields to the wavefunctions are utilized in a bilinear rather than a quadratic lagrangian in these fields. This construction greatly enlarges the gauge group so that now proving causal evolution, relative to the physical metric, for the gauge invariant functions of the fields requires both the stress-energy conservation and probability current conservation laws. Through a Higgs-like coupling term the proto-gravity fields generate a well defined physical metric structure and gives the usual distinguishing of gravity from electromagnetism at low energies relative to the Higgs-like coupling. The flat background induces a full set of conservation laws but results in the need to distinguish these quantities from those observed by recording devices and observers constructed from the fields.
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. Coal Stocks atDistillateGulfExportsAPI Gravity
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. CoalInputs &Futures PricesAPI Gravity
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. CoalInputs &Futures PricesAPI GravityArea
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. CoalInputs &Futures PricesAPIAPI Gravity
Equivalence principle in scalar-tensor gravity
Dirk Puetzfeld; Yuri N. Obukhov
2015-05-06T23:59:59.000Z
We present a direct confirmation of the validity of the equivalence principle for unstructured test bodies in scalar tensor gravity. Our analysis is complementary to previous approaches and valid for a large class of scalar-tensor theories of gravitation. A covariant approach is used to derive the equations of motion in a systematic way and allows for the experimental test of scalar-tensor theories by means of extended test bodies.
Charged Cylindrical Black Holes in Conformal Gravity
Jackson Levi Said; Joseph Sultana; Kristian Zarb Adami
2013-01-04T23:59:59.000Z
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.
QPOs: Einstein's gravity non-linear resonances
Paola Rebusco; Marek A. Abramowicz
2006-01-30T23:59:59.000Z
There is strong evidence that the observed kHz Quasi Periodic Oscillations (QPOs) in the X-ray flux of neutron star and black hole sources in LMXRBs are linked to Einstein's General Relativity. Abramowicz&Klu\\'zniak (2001) suggested a non-linear resonance model to explain the QPOs origin: here we summarize their idea and the development of a mathematical toy-model which begins to throw light on the nature of Einstein's gravity non-linear oscillations.
Twisted covariant noncommutative self-dual gravity
Estrada-Jimenez, S.; Garcia-Compean, H.; Obregon, O.; Ramirez, C. [Centro de Estudios en Fisica y Matematicas Basicas y Aplicadas, Universidad Autonoma de Chiapas, Calle 4 Oriente Norte 1428, Tuxtla Gutierrez, Chiapas (Mexico); Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados del IPN, P.O. Box 14-740, 07000 Mexico D.F. (Mexico); Centro de Investigacion y de Estudios Avanzados del IPN, Unidad Monterrey, PIIT, Via del Conocimiento 201, Autopista nueva al Aeropuerto km 9.5, 66600, Apodaca Nuevo Leon (Mexico); Instituto de Fisica de la Universidad de Guanajuato, P.O. Box E-143, 37150, Leon Gto. (Mexico); Facultad de Ciencias Fisico Matematicas, Universidad Autonoma de Puebla, P.O. Box 1364, 72000, Puebla (Mexico)
2008-12-15T23:59:59.000Z
A twisted covariant formulation of noncommutative self-dual gravity is presented. The formulation for constructing twisted noncommutative Yang-Mills theories is used. It is shown that the noncommutative torsion is solved at any order of the {theta} expansion in terms of the tetrad and some extra fields of the theory. In the process the first order expansion in {theta} for the Plebanski action is explicitly obtained.
Gravity and Yang-Mills amplitude relations
Bjerrum-Bohr, N. E. J.; Damgaard, Poul H.; Soendergaard, Thomas [Niels Bohr International Academy and Discovery Center, Niels Bohr Institute, Blegdamsvej 17, DK-2100, Copenhagen O (Denmark); FengBo [Center of Mathematical Science, Zhejiang University, Hangzhou (China)
2010-11-15T23:59:59.000Z
Using only general features of the S matrix and quantum field theory, we prove by induction the Kawai-Lewellen-Tye relations that link products of gauge theory amplitudes to gravity amplitudes at tree level. As a bonus of our analysis, we provide a novel and more symmetric form of these relations. We also establish an infinite tower of new identities between amplitudes in gauge theories.
Gravity controlled anti-reverse rotation device
Dickinson, Robert J. (Shaler Township, Allegheny County, PA); Wetherill, Todd M. (Lower Burrell, PA)
1983-01-01T23:59:59.000Z
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.
Holographic Superconductors in Horava-Lifshitz Gravity
Kai Lin; Elcio Abdalla; Anzhong Wang
2014-06-18T23:59:59.000Z
We consider holographic superconductors related to the Schwarzschild black hole in the low energy limit of Ho\\v{r}ava-Lifshitz spacetime. The non-relativistic electromagnetic and scalar fields are introduced to construct a holographic superconductor model in Ho\\v{r}ava-Lifshitz gravity and the results show that the $\\alpha_2$ term plays an important role, modifying the conductivity curve line by means of an attenuation the conductivity.
Exact Gravity Dual of a Gapless Superconductor
George Koutsoumbas; Eleftherios Papantonopoulos; George Siopsis
2009-06-17T23:59:59.000Z
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.
Holographic Superconductivity with Gauss-Bonnet gravity
Ruth Gregory
2010-12-07T23:59:59.000Z
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.
Adjuvant and Definitive Radiotherapy for Adrenocortical Carcinoma
Sabolch, Aaron [University of Michigan Medical School, Ann Arbor, MI (United States); Feng, Mary [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Griffith, Kent [Department of Biostatistics Unit, University of Michigan Comprehensive Cancer Center, Ann Arbor, MI (United States); Hammer, Gary [Department of Internal Medicine, University of Michigan, Ann Arbor, MI (United States); Doherty, Gerard [Department of Surgery, University of Michigan, Ann Arbor, MI (United States); Ben-Josef, Edgar, E-mail: edgarb@med.umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States)
2011-08-01T23:59:59.000Z
Purpose: To evaluate the impact of both adjuvant and definitive radiotherapy on local control of adrenocortical carcinoma. Methods and Materials: Outcomes were analyzed from 58 patients with 64 instances of treatment for adrenocortical carcinoma at the University of Michigan's Multidisciplinary Adrenal Cancer Clinic. Thirty-seven of these instances were for primary disease, whereas the remaining 27 were for recurrent disease. Thirty-eight of the treatment regimens involved surgery alone, 10 surgery plus adjuvant radiotherapy, and 16 definitive radiotherapy for unresectable disease. The effects of patient, tumor, and treatment factors were modeled simultaneously using multiple variable Cox proportional hazards regression for associations with local recurrence, distant recurrence, and overall survival. Results: Local failure occurred in 16 of the 38 instances that involved surgery alone, in 2 of the 10 that consisted of surgery plus adjuvant radiotherapy, and in 1 instance of definitive radiotherapy. Lack of radiotherapy use was associated with 4.7 times the risk of local failure compared with treatment regimens that involved radiotherapy (95% confidence interval, 1.2-19.0; p = 0.030). Conclusions: Radiotherapy seems to significantly lower the risk of local recurrence/progression in patients with adrenocortical carcinoma. Adjuvant radiotherapy should be strongly considered after surgical resection.
One-way quantum key distribution: Simple upper bound on the secret key rate
Moroder, Tobias; Luetkenhaus, Norbert [Institute of Theoretical Physics I and Max-Planck Research Group, Institute of Optics, Information and Photonics, University Erlangen-Nuremberg, Staudtstrasse 7, 91058 Erlangen (Germany); Institute for Quantum Computing, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1 (Canada); Curty, Marcos [Institute of Theoretical Physics I and Max-Planck Research Group, Institute of Optics, Information and Photonics, University Erlangen-Nuremberg, Staudtstrasse 7, 91058 Erlangen (Germany)
2006-11-15T23:59:59.000Z
We present a simple method to obtain an upper bound on the achievable secret key rate in quantum key distribution (QKD) protocols that use only unidirectional classical communication during the public-discussion phase. This method is based on a necessary precondition for one-way secret key distillation; the legitimate users need to prove that there exists no quantum state having a symmetric extension that is compatible with the available measurements results. The main advantage of the obtained upper bound is that it can be formulated as a semidefinite program, which can be efficiently solved. We illustrate our results by analyzing two well-known qubit-based QKD protocols: the four-state protocol and the six-state protocol.
Abelian-Higgs strings in Rastall gravity
Eugenio R. Bezerra de Mello; Julio C. Fabris; Betti Hartmann
2015-04-02T23:59:59.000Z
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.
Constraining Torsion with Gravity Probe B
Yi Mao; Max Tegmark; Alan Guth; Serkan Cabi
2007-10-05T23:59:59.000Z
It is well-entrenched folklore that torsion gravity theories predict observationally negligible torsion in the solar system, since torsion (if it exists) couples only to the intrinsic spin of elementary particles, not to rotational angular momentum. We argue that this assumption has a logical loophole which can and should be tested experimentally. In the spirit of action=reaction, if a rotating mass like a planet can generate torsion, then a gyroscope should also feel torsion. Using symmetry arguments, we show that to lowest order, the torsion field around a uniformly rotating spherical mass is determined by seven dimensionless parameters. These parameters effectively generalize the PPN formalism and provide a concrete framework for further testing GR. We construct a parametrized Lagrangian that includes both standard torsion-free GR and Hayashi- Shirafuji maximal torsion gravity as special cases. We demonstrate that classic solar system tests rule out the latter and constrain two observable parameters. We show that Gravity Probe B (GPB) is an ideal experiment for further constraining torsion theories, and work out the most general torsion-induced precession of its gyroscope in terms of our torsion parameters
Cooling, Gravity and Geometry: Flow-driven Massive Core Formation
Fabian Heitsch; Lee Hartmann; Adrianne D. Slyz; Julien E. G. Devriendt; Andreas Burkert
2007-09-15T23:59:59.000Z
We study numerically the formation of molecular clouds in large-scale colliding flows including self-gravity. The models emphasize the competition between the effects of gravity on global and local scales in an isolated cloud. Global gravity builds up large-scale filaments, while local gravity -- triggered by a combination of strong thermal and dynamical instabilities -- causes cores to form. The dynamical instabilities give rise to a local focusing of the colliding flows, facilitating the rapid formation of massive protostellar cores of a few 100 M$_\\odot$. The forming clouds do not reach an equilibrium state, though the motions within the clouds appear comparable to ``virial''. The self-similar core mass distributions derived from models with and without self-gravity indicate that the core mass distribution is set very early on during the cloud formation process, predominantly by a combination of thermal and dynamical instabilities rather than by self-gravity.
New Agegraphic Dark Energy in $f(R)$ Gravity
M. R. Setare
2009-08-03T23:59:59.000Z
In this paper we study cosmological application of new agegraphic dark energy density in the $f(R)$ gravity framework. We employ the new agegraphic model of dark energy to obtain the equation of state for the new agegraphic energy density in spatially flat universe. Our calculation show, taking $nnew agegraphic dark energy model in flat universe in the modified gravity cosmology framework. Also we develop a reconstruction scheme for the modified gravity with $f(R)$ action.
Solar System experiments do not yet veto modified gravity models
Valerio Faraoni
2006-07-05T23:59:59.000Z
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.
AdS waves as exact solutions to quadratic gravity
Guellue, Ibrahim; Sisman, Tahsin Cagri; Tekin, Bayram [Department of Physics, Middle East Technical University, 06531 Ankara (Turkey); Guerses, Metin [Department of Mathematics, Faculty of Sciences Bilkent University, 06800 Ankara (Turkey)
2011-04-15T23:59:59.000Z
We give an exact solution of the quadratic gravity in D dimensions. The solution is a plane-fronted wave metric with a cosmological constant. This metric solves not only the full quadratic gravity field equations but also the linearized ones which include the linearized equations of the recently found critical gravity. A subset of the solutions change the asymptotic structure of the anti-de Sitter space due to their logarithmic behavior.
Analysis of faults using gravity methods in Mason County, Texas
Milligan, Michael Glen
1992-01-01T23:59:59.000Z
Committee: Dr. D. A. Fahlquist Dr. B. Johnson The objective of this study is to determine the applicability of gravity profiling methods for determining the location and throw of a series of faults related to a structural graben in northern Mason County... profiles. For two faults with the best geologic control, the best-fit gravity models compared favorably with the the geologic model constructed by Randolph (1991) on the basis of surface mapping, structural control and well control. The gravity models...
Gravity interpretation of the northern Overthrust Belt, Idaho and Wyoming
Silver, Wendy Ilene
1979-01-01T23:59:59.000Z
provide a potential source of information about the configuration of the sedimentary rock / Precambrian basement interface as well as the geometry of the overlying younger rocks. GRAVITY DA. A Regional Gravity The regional gravity field of Wyoming..., Jurassic and Lower Cretaceous units. It may therefore be concluded that the uplifts of the Precambrian basement were fomed after the deposition of those overly1ng sedimentary rocks. ACKNOWLEDGEMEWTS I w1sh to thank Dr, R. R. Berg, chairman of my...
asymptotically safe gravity: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
at high energies. Elisa Manrique; Stefan Rechenberger; Frank Saueressig 2011-02-24 2 Fractal Spacetime Structure in Asymptotically Safe Gravity General Relativity & Quantum...
Ground Gravity Survey At Valles Caldera - Sulphur Springs Geothermal...
Survey Activity Date - 1986 Usefulness not indicated DOE-funding Unknown Notes A computer program capable of two-dimensional modeling of gravity data was used in interpreting...
Quantized gauge-affine gravity in the superfiber bundle approach
A. Meziane; M. Tahiri
2005-11-10T23:59:59.000Z
The quantization of gauge-affine gravity within the superfiber bundle formalism is proposed. By introducing an even pseudotensorial 1-superform over a principal superfibre bundle with superconnection, we obtain the geometrical Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST transformations of the fields occurring in such a theory. Reducing the four-dimensional general affine group double-covering to the Poincare group double-covering we also find the BRST and anti-BRST transformations of the fields present in Einstein's gravity. Furthermore, we give a prescription leading to the construction of both BRST-invariant gauge-fixing action for gauge-affine gravity and Einstein's gravity.
atmospheric gravity waves: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
gravity waves (AGWs). Satellite imagery shows evidence the characteristics of these waves. The favorable wave propagation conditions in 12;this region are illustrated 5...
Integration of Full Tensor Gravity and ZTEM Passive Low Frequency...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
and ZTEM Passive Low Frequency EM Instruments for Simultaneous Data Acquisition Integration of Full Tensor Gravity and ZTEM Passive Low Frequency EM Instruments for...
Ground Gravity Survey At Blue Mountain Geothermal Area (Fairbank...
Fairbank Engineering Ltd, 2003) Exploration Activity Details Location Blue Mountain Geothermal Area Exploration Technique Ground Gravity Survey Activity Date Usefulness not...
Ground Gravity Survey At San Francisco Volcanic Field Area (Warpinski...
Exploration Technique Ground Gravity Survey Activity Date Usefulness not indicated DOE-funding Unknown Notes Northern Arizona University has re-assessed the existing exploration...
Exercise protocols during short-radius centrifugation for artificial gravity
Edmonds, Jessica Leigh
2008-01-01T23:59:59.000Z
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 ...
The f(R) Gravity Function of the Linde Quintessence
Sergei V. Ketov; Natsuki Watanabe
2014-10-20T23:59:59.000Z
We calculate the f(R) gravity function in the dual gravity description of the quintessence model with a quadratic (Linde) scalar potential and a positive cosmological constant. We find that in the large curvature regime relevant to chaotic inflation in early Universe, the dual f(R) gravity is well approximated by the (matter) loop-corrected Starobinsky inflationary model. In the small curvature regime relevant to dark energy in the present Universe, the f(R) gravity function reduces to the Einstein-Hilbert one with a positive cosmological constant.
Ground Gravity Survey At Lake City Hot Springs Area (Warpinski...
fault zones. The focus of Lake City Geothermal's current effort is on enhancing the site interpretation by re-evaluating the existing seismic data, conducting a detailed gravity...
Lessons in quantum gravity from quantum field theory
Berenstein, David [Department of Physics, University of California at Santa Barbara, CA 93106 (United States); Institute for Advanced Study, School of Natural Science, Princeton, NJ 08540 (United States)
2010-12-07T23:59:59.000Z
This paper reviews advances in the understanding of quantum gravity based on field theory calculations in the AdS/CFT correspondence.
Ground Gravity Survey At Dixie Valley Geothermal Area (Allis...
DOE-funding Unknown Exploration Basis Gravity surveys were conducted to monitor the evolution of the geothermal reservoir. Notes A 12 month long experiment was conducted using a...
Summary of Session A6: Alternative Theories of Gravity
R. B. Mann
1998-03-13T23:59:59.000Z
This is a summary of the workshop A.6 on Alternative Theories of Gravity, prepared for the proceedings for the GR15 conference.
Ground Gravity Survey At Long Valley Caldera Geothermal Area...
Battaglia, Et Al., 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Long Valley Caldera Geothermal Area (Battaglia,...
Strong and weak gravitational field in $R+?^4/R$ gravity
Kh. Saaidi; A. Vajdi; S. W. Rabiei; A. Aghamohammadi; H. Sheikhahmadi
2012-01-18T23:59:59.000Z
We introduce a new approach for investigating the weak field limit of vacuum field equations in $f(R)$ gravity and we find the weak field limit of $f(R)=R+\\mu ^4/R$ gravity. Furthermore, we study the strong gravity regime in $R+\\mu^{4}/R$ model of $f(R)$ gravity. We show the existence of strong gravitational field in vacuum for such model. We find out in the limit $\\mu\\rightarrow 0$, the weak field limit and the strong gravitational field can be regarded as a perturbed Schwarzschild metric.
authenticated key agreement: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
desirable attributes. Index Terms--Mutual Authentication; Key Management; SRP; Security; Smart Meter; Smart Leung, Victor C.M. 53 On the security of some password-based key...
"Turn-Key" Open Source Software Solutions for Energy Management...
"Turn-Key" Open Source Software Solutions for Energy Management of Small to Medium Sized Buildings (DE-FOA-0000822) "Turn-Key" Open Source Software Solutions for Energy Management...
Quantum Key Distribution by Utilizing Four-Level Particles
Tao Yan; Fengli Yan
2010-02-09T23:59:59.000Z
We present a quantum key distribution protocol based on four-level particles entanglement. Furthermore, a controlled quantum key distribution protocol is proposed by utilizing three four-level particles. We show that the two protocols are secure.
The impacts of urbanization on endangered florida key deer
Harveson, Patricia Moody
2006-04-12T23:59:59.000Z
for resources between man and wildlife continues, it is important to understand the effects of urbanization on species. Endangered Key deer (Odocoileus virginianus clavium) are endemic to the Florida Keys archipelago stretching southwest off the southern tip...
Exploring the context : a small hotel in Key West
VanBeuzekom, Edrick
1984-01-01T23:59:59.000Z
This thesis develops a personal method and approach for designing in a delicate context such as the Key West Historic District. This thesis is composed of two parts. The first part presents observations of Key West, focusing ...
actual key success: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
key exchange over an insecure channel. The security of the proposed algorithm grows as NPm, where M, P are the size of the key and the computational commplexity fo the linear...
access technologies key: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
key exchange over an insecure channel. The security of the proposed algorithm grows as NPm, where M, P are the size of the key and the computational commplexity fo the linear...
Turn Your Key, Be Idle Free | Department of Energy
Broader source: Energy.gov (indexed) [DOE]
Turn Your Key, Be Idle Free Turn Your Key, Be Idle Free April 13, 2010 - 7:30am Addthis Shannon Brescher Shea Communications Manager, Clean Cities Program What activity wastes...
Low-density random matrices for secret key extraction
Zhou, Hongchao
Secret key extraction, the task of extracting a secret key from shared information that is partially known by an eavesdropper, has important applications in cryptography. Motivated by the requirements of high-speed quantum ...
Secret key agreement using asymmetry in channel state knowledge
Wornell, Gregory W.
We study secret-key agreement protocols over a wiretap channel controlled by a state parameter. The secret-key capacity is established when the wiretap channel is discrete and memoryless, the sender and receiver are both ...
Compression station key to Texas pipeline project
NONE
1996-10-01T23:59:59.000Z
This was probably the largest pipeline project in the US last year, and the largest in Texas in the last decade. The new compressor station is a key element in this project. TECO, its servicing dealer, and compression packager worked closely throughout the planning and installation stages of the project. To handle the amount of gas required, TECO selected the GEMINI F604-1 compressor, a four-throw, single-stage unit with a six-inch stroke manufactured by Weatherford Enterra Compression Co. (WECC) in Corpus Christi, TX. TECO also chose WECC to package the compressors. Responsibility for ongoing support of the units will be shared among TECO, the service dealer and the packager. TECO is sending people to be trained by WECC, and because the G3600 family of engines is still relatively new, both the Caterpillar dealer and WECC sent people for advanced training at Caterpillar facilities in Peoria, IL. As part of its service commitment to TECO, the servicing dealer drew up a detailed product support plan, encompassing these five concerns: Training, tooling; parts support; service support; and commissioning.
Relationship between key events in Earth history
Gillman, Michael
2015-01-01T23:59:59.000Z
A model of cyclical (sinusoidal) motion of the solar system, intercepting event lines distributed at fixed intervals, explains the pattern of timings of mass extinctions, earlier glaciations, largest impact craters and the largest known extrusions of magma in the history of the Earth. The model reveals links between several sets of key events, including the end-Cretaceous and end-Ordovician extinctions with the Marinoan glaciation, and the end-Permian with the end-Serpukhovian extinctions. The model is supported by significant clusters of events and a significant reduction of impact crater size with position (sine value). The pattern of event lines is sustained to the earliest-dated impact craters (2023 and 1849 Ma) and to the origin of the solar system, close to 4567.4 Ma. The implication is that, for the entirety of its existence, the solar system has passed in a consistent manner through a predictably structured galaxy. Dark matter is a possible contender for the structure determining the event lines.
Residential Energy Efficiency Financing: Key Elements of Program Design
Broader source: Energy.gov [DOE]
Presents key programmatic elements and context of financing initiatives, including contractor support, rebates, quality assurance, and more.
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. Coal StocksArea Definitions
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. Coal StocksArea DefinitionsRail between PAD
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. Coal StocksArea DefinitionsRail between
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. Coal StocksArea DefinitionsRail
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. Coal StocksArea DefinitionsRailTanker and
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. Coal StocksArea DefinitionsRailTanker
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. Coal StocksArea DefinitionsRailTankerImports
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. Coal StocksAreaChargeInput Definitions
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. Coal StocksAreaChargeInputYield Definitions
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. CoalInputs & Utilization Definitions
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. CoalInputsTotal Stocks Definitions
Table Definitions, Sources, and Explanatory Notes
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Energy I I' a(STEO)U.S. CoalInputsTotal Stocks DefinitionsWeekly
A Full Key Recovery Attack on HMAC-AURORA-512
A Full Key Recovery Attack on HMAC-AURORA-512 Yu Sasaki NTT Information Sharing Platform.yu@lab.ntt.co.jp Abstract. In this note, we present a full key recovery attack on HMAC- AURORA-512 when 512-bit secret keys is 2259 AURORA-512 operations, which is significantly less than the complexity of the exhaustive search
Why Hierarchical Key Distribution is Appropriate for Multicast Networks
Zheng, Yuliang
Why Hierarchical Key Distribution is Appropriate for Multicast Networks Chandana Gamage, Jussipekka rationale for many key distribution schemes for multicast networks are based on heuristic arguments on e of multicast group formation and network growth to look at the selection of a key distribution scheme from
Secret-key generation with correlated sources and noisy channels
Khisti, Ashish
Secret-key generation with correlated sources and noisy channels Ashish Khisti EECS Dept. MIT for secret-key generation between remote terminals is considered. The sender communicates to the receiver discrete memoryless sources. Lower and upper bounds for the secret-key rate are presented and shown
Interactive Secret Key Generation over Reciprocal Fading Channels
Khisti, Ashish
Interactive Secret Key Generation over Reciprocal Fading Channels Ashish Khisti Dept. of Electrical--We study a two-terminal secret-key generation problem over a two-way, approximately reciprocal, block of the secret-key is gen- erated from the correlated channel state sequences by creating omniscience between
Protecting Secret Keys with Personal Entropy Carl Ellison
Schneier, Bruce
Protecting Secret Keys with Personal Entropy Carl Ellison Cybercash, Inc., cme@cybercash.com Chris technology often requires users to protect a secret key by selecting a password or passphrase. While a good to recover the secret key. As time passes, the ability to remember the passphrase fades and the user may
Secret-Key Generation over Reciprocal Fading Channels
Khisti, Ashish
Secret-Key Generation over Reciprocal Fading Channels Ashish Khisti Department of Electrical and Computer Engineering University of Toronto Nov. 14, 2012 #12;Motivation Secret-Key Generation in Wireless, 2012 2/ 22 #12;Motivation Secret-Key Generation in Wireless Fading Channels A B KA KB Forward
Secret-Key Generation from Channel Reciprocity: A Separation Approach
Khisti, Ashish
Secret-Key Generation from Channel Reciprocity: A Separation Approach Ashish Khisti Department: Secret-Key Generation Secure Message Transmission Physical Layer Authentication Jamming Resistance Feb 11, 2013 2/ 20 #12;Motivation Secret-Key Generation in Wireless Fading Channels A B KA KB Forward
Security proof for quantum key distribution using qudit systems
Sheridan, Lana [Centre for Quantum Technologies, National University of Singapore (Singapore); Scarani, Valerio [Centre for Quantum Technologies, National University of Singapore (Singapore); Department of Physics, National University of Singapore (Singapore)
2010-09-15T23:59:59.000Z
We provide security bounds against coherent attacks for two families of quantum key distribution protocols that use d-dimensional quantum systems. In the asymptotic regime, both the secret key rate for fixed noise and the robustness to noise increase with d. The finite key corrections are found to be almost insensitive to d < or approx. 20.
Secure Broadcasting of a Common Message with Independent Secret Keys
Khisti, Ashish
Secure Broadcasting of a Common Message with Independent Secret Keys Rafael F. Schaefer Department broadcasting with indepen- dent secret keys is studied. The particular scenario is analyzed where a common of it. The transmitter shares independent secret keys of arbitrary rates with both legitimate receivers
Dynamic Key Ring Update Mechanism for Mobile Wireless Sensor Networks
Yanikoglu, Berrin
@sabanciuniv.edu Abstract--Key distribution is an important issue to provide security in Wireless Sensor Networks (WSNs. For the performance evaluation basis, we used our mechanism together with a location based key pre-distribution scheme Terms--mobile wireless sensor networks, key ring update, security, resiliency, connectivity I
A new quasidilaton theory of massive gravity
Shinji Mukohyama
2014-10-08T23:59:59.000Z
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.
Fractal Spacetime Structure in Asymptotically Safe Gravity
O. Lauscher; M. Reuter
2005-08-26T23:59:59.000Z
Four-dimensional Quantum Einstein Gravity (QEG) is likely to be an asymptotically safe theory which is applicable at arbitrarily small distance scales. On sub-Planckian distances it predicts that spacetime is a fractal with an effective dimensionality of 2. The original argument leading to this result was based upon the anomalous dimension of Newton's constant. In the present paper we demonstrate that also the spectral dimension equals 2 microscopically, while it is equal to 4 on macroscopic scales. This result is an exact consequence of asymptotic safety and does not rely on any truncation. Contact is made with recent Monte Carlo simulations.
Gamma Ray Burst Neutrinos Probing Quantum Gravity
M. C. Gonzalez-Garcia; F. Halzen
2006-11-28T23:59:59.000Z
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.
Dynamics of generalized Palatini theories of gravity
Vitagliano, Vincenzo; Liberati, Stefano [SISSA-International School for Advanced Studies, Via Bonomea 265, 34136 Trieste (Italy) and INFN sezione di Trieste, sezione di Trieste, via Valerio 2, 34127 Trieste (Italy); Sotiriou, Thomas P. [Department of Applied Mathematics and Theoretical Physics, Center for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)
2010-10-15T23:59:59.000Z
It is known that in f(R) theories of gravity with an independent connection which can be both nonmetric and nonsymmetric, this connection can always be algebraically eliminated in favor of the metric and the matter fields, so long as it is not coupled to the matter explicitly. We show here that this is a special characteristic of f(R) actions, and it is not true for actions that include other curvature invariants. This contradicts some recent claims in the literature. We clarify the reasons for this contradiction.
Modification of gravity due to torsion
Nair, V. P. [Physics Department, City College of the CUNY, New York, NY 10031 (United States); Nikiforova, V. [Physics Department, Mascow State University Moscow (Russian Federation); Randjbar-Daemi, S. [The Abdus Salam International Centre for Theoretical Physics, Trieste (Italy); Rubakov, V. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation)
2010-01-01T23:59:59.000Z
Modifications of general relativity have been considered as one of the possible ways of addressing some of the outstanding problems related to the large scale gravitational physics. In this contribution we review some of the recent results which are due to the inclusion of dynamical torsion. More specifically we shall discuss the propagation of massive spin-2 particles in flat and curved space times. We shall show that, contrary to what is generally believed, spinning matter is not the sole source of torsion field. A symmetric energy momentum tensor can also couple to torsion degrees of freedom. The massive and massless spin-2 particles mix giving rise to an infrared modification of gravity.
A high frequency resonance gravity gradiometer
Bagaev, S. N.; Kvashnin, N. L.; Skvortsov, M. N. [Laser Physics Institute SB RAS, Novosibirsc (Russian Federation); Bezrukov, L. B.; Krysanov, V. A. [Institute of Nuclear Physics RAS, Moscow (Russian Federation); Oreshkin, S. I.; Motylev, A. M.; Popov, S. M.; Samoilenko, A. A.; Yudin, I. S. [Lomonosov MSU, Sternberg Astronomical Institute, Moscow (Russian Federation); Rudenko, V. N. [Institute of Nuclear Physics RAS, Moscow (Russian Federation); Lomonosov MSU, Sternberg Astronomical Institute, Moscow (Russian Federation)
2014-06-15T23:59:59.000Z
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.
Confronting Dilaton-exchange gravity with experiments
H. V. Klapdor-Kleingrothaus; H. Päs; U. Sarkar
2000-08-16T23:59:59.000Z
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.
Wave Packets Propagation in Quantum Gravity
Kourosh Nozari; S. H. Mehdipour
2005-07-03T23:59:59.000Z
Wave packet broadening in usual quantum mechanics is a consequence of dispersion behavior of the medium which the wave propagates in it. In this paper, we consider the problem of wave packet broadening in the framework of Generalized Uncertainty Principle(GUP) of quantum gravity. New dispersion relations are derived in the context of GUP and it has been shown that there exists a gravitational induced dispersion which leads to more broadening of the wave packets. As a result of these dispersion relations, a generalized Klein-Gordon equation is obtained and its interpretation is given.
Anisotropic higher derivative gravity and inflationary universe
W. F. Kao
2006-05-21T23:59:59.000Z
Stability analysis of the Kantowski-Sachs type universe in pure higher derivative gravity theory is studied in details. The non-redundant generalized Friedmann equation of the system is derived by introducing a reduced one dimensional generalized KS type action. This method greatly reduces the labor in deriving field equations of any complicate models. Existence and stability of inflationary solution in the presence of higher derivative terms are also studied in details. Implications to the choice of physical theories are discussed in details in this paper.
Inflationary Universe in Higher Derivative Induced Gravity
W. F. Kao
2000-06-27T23:59:59.000Z
In an induced-gravity model, the stability condition of an inflationary slow-rollover solution is shown to be $\\phi_0 \\partial_{\\phi_0}V(\\phi_0)=4V(\\phi_0)$. The presence of higher derivative terms will, however, act against the stability of this expanding solution unless further constraints on the field parameters are imposed. We find that these models will acquire a non-vanishing cosmological constant at the end of inflation. Some models are analyzed for their implication to the early universe.
Loop Quantum Gravity: An Inside View
Thomas Thiemann
2006-08-29T23:59:59.000Z
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.
Hall viscosity from gauge/gravity duality
Omid Saremi; Dam Thanh Son
2011-03-24T23:59:59.000Z
In (2+1)-dimensional systems with broken parity, there exists yet another transport coefficient, appearing at the same order as the shear viscosity in the hydrodynamic derivative expansion. In condensed matter physics, it is referred to as "Hall viscosity". We consider a simple holographic realization of a (2+1)-dimensional isotropic fluid with broken spatial parity. Using techniques of fluid/gravity correspondence, we uncover that the holographic fluid possesses a nonzero Hall viscosity, whose value only depends on the near-horizon region of the background. We also write down a Kubo's formula for the Hall viscosity. We confirm our results by directly computing the Hall viscosity using the formula.
Thermodynamics of 5D dilaton-gravity
Megias, E. [Institute for Theoretical Physics, University of Heidelberg (Germany); Instituto de Fisica Teorica CSIC-UAM, Universidad Autonoma de Madrid (Spain)
2011-05-23T23:59:59.000Z
We calculate the free energy, spatial string tension and Polyakov loop of the gluon plasma using the dilaton potential of Ref. [1] in the dilaton-gravity theory of AdS/QCD. The free energy is computed from the Black Hole solutions of the Einstein equations in two ways: first, from the Bekenstein-Hawking proportionality of the entropy with the area of the horizon, and secondly from the Page-Hawking computation of the free energy. The finite temperature behaviour of the spatial string tension and Polyakov loop follow from the corresponding string theory in AdS{sub 5}. Comparison with lattice data is made.
Holographic renormalization of new massive gravity
Alishahiha, Mohsen [School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Naseh, Ali [School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Department of Physics, Sharif University of Technology, P.O. Box 11365-9161, Tehran (Iran, Islamic Republic of)
2010-11-15T23:59:59.000Z
We study holographic renormalization for three-dimensional new massive gravity. By studying the general falloff conditions for the metric allowed by the model at infinity, we show that at the critical point where the central charges of the dual conformal field theory (CFT) are zero, it contains a leading logarithmic behavior. In the context of AdS/CFT correspondence it can be identified as a source for an irrelevant operator in the dual CFT. The presence of the logarithmic falloff may be interpreted as the fact that the dual CFT would be a logarithmic conformal field theory.
Gravity dual of spatially modulated phase
Nakamura, Shin [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan); Ooguri, Hirosi [California Institute of Technology, Pasadena, California 91125 (United States); IPMU, University of Tokyo, Kashiwa 277-8586 (Japan); Park, Chang-Soon [California Institute of Technology, Pasadena, California 91125 (United States)
2010-02-15T23:59:59.000Z
We show that the five-dimensional Maxwell theory with the Chern-Simons term is tachyonic in the presence of a constant electric field. When coupled to gravity, a sufficiently large Chern-Simons coupling causes instability of the Reissner-Nordstroem black holes in anti-de Sitter space. The instability happens only at nonvanishing momenta, suggesting a spatially modulated phase in the holographically dual quantum field theory in (3+1) dimensions, with spontaneous current generation in a helical configuration. The three-charge extremal black hole in the type IIB superstring theory on AdS{sub 5}xS{sup 5} barely satisfies the stability condition.
Apparent horizon in fluid-gravity duality
Booth, Ivan; Heller, Michal P.; Plewa, Grzegorz; Spalinski, Michal [Department of Mathematics and Statistics, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, A1C 5S7 (Canada); Instituut voor Theoretische Fysica, Universiteit van Amsterdam, Science Park 904, 1090 GL Amsterdam (Netherlands); Soltan Institute for Nuclear Studies, Hoza 69, 00-681 Warsaw (Poland); Soltan Institute for Nuclear Studies, Hoza 69, 00-681 Warsaw (Poland) and Physics Department, University of Bialystok, 15-424 Bialystok (Poland)
2011-05-15T23:59:59.000Z
This article develops a computational framework for determining the location of boundary-covariant apparent horizons in the geometry of conformal fluid-gravity duality in arbitrary dimensions. In particular, it is shown up to second order and conjectured to hold to all orders in the gradient expansion that there is a unique apparent horizon which is covariantly expressible in terms of fluid velocity, temperature, and boundary metric. This leads to the first explicit example of an entropy current defined by an apparent horizon and opens the possibility that in the near-equilibrium regime there is preferred foliation of apparent horizons for black holes in asymptotically anti-de Sitter spacetimes.
Seven-dimensional gravity with topological terms
Lue, H. [China Economics and Management Academy Central, University of Finance and Economics, Beijing 100081 (China); Institute for Advanced Study, Shenzhen University, Nanhai Ave 3688, Shenzhen 518060 (China); Pang Yi [Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190 (China)
2010-04-15T23:59:59.000Z
We construct new seven-dimensional gravity by adding two topological terms to the Einstein-Hilbert action. For a certain choice of the coupling constants, these terms exist naturally in seven-dimensional gauged supergravity from the S{sup 4} reduction of eleven-dimensional supergravity with the R{sup 4} corrections. We derive the full set of the equations of motion. We find that the static spherically-symmetric black holes are unmodified by the topological terms. We obtain squashed AdS{sub 7}, and also squashed seven spheres and Q{sup 111} spaces in Euclidean signature.
Drag phenomena from holographic massive gravity
Matteo Baggioli; Daniel K. Brattan
2015-04-28T23:59:59.000Z
We consider the motion of point particles in a strongly coupled field theory with broken translation invariance. We obtain the energy and momentum loss rates and drag coefficients for a class of such particles by solving for the motion of classical strings in holographic massive gravity. At low temperatures compared to the graviton mass the behaviour of the string is controlled by the appearance of an exotic ground state with non-zero entropy at zero temperature. Additionally we find an upper bound on the diffusion constant for a collection of these particles which is saturated when the mass of the graviton goes to zero.
Drag phenomena from holographic massive gravity
Baggioli, Matteo
2015-01-01T23:59:59.000Z
We consider the motion of point particles in a strongly coupled field theory with broken translation invariance. We obtain the energy and momentum loss rates and drag coefficients for a class of such particles by solving for the motion of classical strings in holographic massive gravity. At low temperatures compared to the graviton mass the behaviour of the string is controlled by the appearance of an exotic ground state with non-zero entropy at zero temperature. Additionally we find an upper bound on the diffusion constant for a collection of these particles which is saturated when the mass of the graviton goes to zero.
Category:Gravity Techniques | Open Energy Information
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Advanced Gasifier Pilot Plant Concept Definition
Steve Fusselman; Alan Darby; Fred Widman
2005-08-31T23:59:59.000Z
This report presents results from definition of a preferred commercial-scale advanced gasifier configuration and concept definition for a gasification pilot plant incorporating those preferred technologies. The preferred commercial gasifier configuration was established based on Cost Of Electricity estimates for an IGCC. Based on the gasifier configuration trade study results, a compact plug flow gasifier, with a dry solids pump, rapid-mix injector, CMC liner insert and partial quench system was selected as the preferred configuration. Preliminary systems analysis results indicate that this configuration could provide cost of product savings for electricity and hydrogen ranging from 15%-20% relative to existing gasifier technologies. This cost of product improvement draws upon the efficiency of the dry feed, rapid mix injector technology, low capital cost compact gasifier, and >99% gasifier availability due to long life injector and gasifier liner, with short replacement time. A pilot plant concept incorporating the technologies associated with the preferred configuration was defined, along with cost and schedule estimates for design, installation, and test operations. It was estimated that a 16,300 kg/day (18 TPD) pilot plant gasifier incorporating the advanced gasification technology and demonstrating 1,000 hours of hot-fire operation could be accomplished over a period of 33 months with a budget of $25.6 M.
Definition of heavy oil and natural bitumen
Meyer, R.F.
1988-08-01T23:59:59.000Z
Definition and categorization of heavy oils and natural bitumens are generally based on physical or chemical attributes or on methods of extraction. Ultimately, the hydrocarbon's chemical composition will govern both its physical state and the extraction technique applicable. These oils and bitumens closely resemble the residuum from wholecrude distillation to about 1,000/degree/F; if the residuum constitutes at least 15% of the crude, it is considered to be heavy. In this material is concentrated most of the trace elements, such as sulfur, oxygen, and nitrogen, and metals, such as nickel and vanadium. A widely used definition separates heavy oil from natural bitumen by viscosity, crude oil being less, and bitumen more viscous than 10,000 cp. Heavy crude then falls in the range 10/degree/-20/degree/ API inclusive and extra-heavy oil less than 10/degree/ API. Most natural bitumen is natural asphalt (tar sands, oil sands) and has been defined as rock containing hydrocarbons more viscous than 10,000 cp or else hydrocarbons that may be extracted from mined or quarried rock. Other natural bitumens are solids, such as gilsonite, grahamite, and ozokerite, which are distinguished by streak, fusibility, and solubility. The upper limit for heavy oil may also be set at 18/degree/ API, the approximate limit for recovery by waterflood.
Gravity waves excited by jets: Propagation versus generation R. Plougonven
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 simulations demonstrate that the propagation of inertia-gravity waves through horizontal deformation
Gravity Field and Internal Structure of Mercury from MESSENGER
Zuber, Maria
,5 Mark E. Perry,11 David D. Rowlands,5 Sander Goossens,12 James W. Head,13 Anthony H. Taylor14 RadioGravity Field and Internal Structure of Mercury from MESSENGER David E. Smith,1 Maria T. Zuber,1 tracking of the MESSENGER spacecraft has provided a model of Mercury's gravity field. In the northern
Wavelet based inversion of gravity data Fabio Boschetti
Boschetti, Fabio
1 Wavelet based inversion of gravity data Fabio Boschetti CSIRO Exploration & Mining and Australian Running Heading: Wavelet based inversion of gravity data #12;2 ABSTRACT The Green's function of the Poisson equation, and its spatial derivatives, lead to a family of wavelets specifically tailored
Cosmological evolutions of $F(R)$ nonlinear massive gravity
De-Jun Wu
2014-03-24T23:59:59.000Z
Recently a new extended nonlinear massive gravity model has been proposed which includes the $F(R)$ modifications to dRGT model.We follow the $F(R)$ nonlinear massive gravity and study its implications on cosmological evolutions. We derive the critical points of the cosmic system and study the corresponding kinetics by performing the phase-plane analysis.
Mapping crustal thickness using marine gravity data: Methods and uncertainties
Müller, Dietmar
of petroleum systems within passive margins. However, direct measurements of crustal thickness are sparse geophysical data, to estimate crustal thickness. We evaluated alternative gravity inversion methodol- ogies, but economic considerations make gravity modeling a more practical approach for mapping crustal thickness over
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
2015-05-01T23:59:59.000Z
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.
Definition et unites Sources d'energie primaire
Ravelet, Florent
D´efinition et unit´es Sources d'´energie primaire L'´energie dans une perspective historique Etat Laboratoire DynFluid, Arts et M´etiers-ParisTech 19 f´evrier 2014 F. Ravelet Energies #12;D´efinition et unit Energies #12;D´efinition et unit´es Sources d'´energie primaire L'´energie dans une perspective historique
Secret key distillation from shielded two-qubit states
Joonwoo Bae
2010-09-22T23:59:59.000Z
The quantum states corresponding to a secret key are characterized using the so-called private states, where the key part consisting of a secret key is shielded by the additional systems. Based on the construction, it was shown that a secret key can be distilled from bound entangled states. In this work, I consider the shielded two-qubit states in a key-distillation scenario and derive the conditions under which a secret key can be distilled using the recurrence protocol or the two-way classical distillation, advantage distillation together with one-way postprocessing. From the security conditions, it is shown that a secret key can be distilled from bound entangled states in a much wider range. In addition, I consider the case that in which white noise is added to quantum states and show that the classical distillation protocol still works despite a certain amount of noise although the recurrence protocol does not.
Secret key distillation from shielded two-qubit states
Bae, Joonwoo [School of Computational Sciences, Korea Institute for Advanced Study, Seoul 130-722 (Korea, Republic of)
2010-05-15T23:59:59.000Z
The quantum states corresponding to a secret key are characterized using the so-called private states, where the key part consisting of a secret key is shielded by the additional systems. Based on the construction, it was shown that a secret key can be distilled from bound entangled states. In this work, I consider the shielded two-qubit states in a key-distillation scenario and derive the conditions under which a secret key can be distilled using the recurrence protocol or the two-way classical distillation, advantage distillation together with one-way postprocessing. From the security conditions, it is shown that a secret key can be distilled from bound entangled states in a much wider range. In addition, I consider the case that in which white noise is added to quantum states and show that the classical distillation protocol still works despite a certain amount of noise although the recurrence protocol does not.
Dipole gravity waves from unbound quadrupoles
Felber, Franklin
2010-01-01T23:59:59.000Z
Dipole gravitational disturbances from gravitationally unbound mass quadrupoles propagate to the radiation zone with signal strength at least of quadrupole order if the quadrupoles are nonrelativistic, and of dipole order if relativistic. Angular distributions of parallel-polarized and transverse-polarized dipole power in the radiation zone are calculated for simple unbound quadrupoles, like a linear-oscillator/stress-wave pair and a particle storage ring. Laboratory tests of general relativity through measurements of dipole gravity waves in the source region are proposed. A NASA G2 flywheel module with a modified rotor can produce a post-Newtonian dc bias signal at a gradiometer up to 1 mE. At peak luminosity, the repulsive dipole impulses of proton bunches at the LHC can produce an rms velocity of a high-Q detector surface up to 4 micron/s. Far outside the source region, Newtonian lunar dipole gravity waves can produce a 1-cm displacement signal at LISA. Dipole signal strengths of astrophysical events invol...
Dipole gravity waves from unbound quadrupoles
Franklin Felber
2010-06-10T23:59:59.000Z
Dipole gravitational disturbances from gravitationally unbound mass quadrupoles propagate to the radiation zone with signal strength at least of quadrupole order if the quadrupoles are nonrelativistic, and of dipole order if relativistic. Angular distributions of parallel-polarized and transverse-polarized dipole power in the radiation zone are calculated for simple unbound quadrupoles, like a linear-oscillator/stress-wave pair and a particle storage ring. Laboratory tests of general relativity through measurements of dipole gravity waves in the source region are proposed. A NASA G2 flywheel module with a modified rotor can produce a post-Newtonian dc bias signal at a gradiometer up to 1 mE. At peak luminosity, the repulsive dipole impulses of proton bunches at the LHC can produce an rms velocity of a high-Q detector surface up to 4 micron/s. Far outside the source region, Newtonian lunar dipole gravity waves can produce a 1-cm displacement signal at LISA. Dipole signal strengths of astrophysical events involving unbound quadrupoles, like near collisions and neutron star kicks in core-collapse supernovae, are estimated.
A dynamical inconsistency of Horava gravity
Henneaux, Marc [Universite Libre de Bruxelles and International Solvay Institutes, ULB-Campus Plaine CP231, 1050 Brussels (Belgium); Centro de Estudios Cientificos (CECS), Casilla 1469, Valdivia (Chile); Kleinschmidt, Axel; Lucena Gomez, Gustavo [Universite Libre de Bruxelles and International Solvay Institutes, ULB-Campus Plaine CP231, 1050 Brussels (Belgium)
2010-03-15T23:59:59.000Z
The dynamical consistency of the nonprojectable version of Horava gravity is investigated by focusing on the asymptotically flat case. It is argued that for generic solutions of the constraint equations the lapse must vanish asymptotically. We then consider particular values of the coupling constants for which the equations are tractable and in that case we prove that the lapse must vanish everywhere--and not only at infinity. Put differently, the Hamiltonian constraints are generically all second-class. We then argue that the same feature holds for generic values of the couplings, thus revealing a physical inconsistency of the theory. In order to cure this pathology, one might want to introduce further constraints but the resulting theory would then lose much of the appeal of the original proposal by Horava. We also show that there is no contradiction with the time-reparametrization invariance of the action, as this invariance is shown to be a so-called 'trivial gauge symmetry' in Horava gravity, hence with no associated first-class constraints.
Spherically symmetric conformal gravity and "gravitational bubbles"
V. A. Berezin; V. I. Dokuchaev; Yu. N. Eroshenko
2014-12-09T23:59:59.000Z
The general structure of the spherically symmetric solutions in the Weyl conformal gravity is described. The corresponding Bach equation are derived for the special type of metrics, which can be considered as the representative of the general class. The complete set of the pure vacuum solutions is found. It consists of two classes. The first one contains the solutions with constant two-dimensional curvature scalar of our specific metrics, and the representatives are the famous Robertson-Walker metrics. One of them we called the "gravitational bubbles", which is compact and with zero Weyl tensor. The second class is more general, with varying curvature scalar. We found its representative as the one-parameter family. It appears that it can be conformally covered by the thee-parameter Mannheim-Kazanas solution. We also investigated the general structure of the energy-momentum tensor in the spherical conformal gravity and constructed the vectorial equation that reveals clearly the same features of non-vacuum solutions. One of them, the metrics a la Vaidya, is explicitly written.
Vacuum energy: quantum hydrodynamics vs quantum gravity
G. E. Volovik
2005-09-09T23:59:59.000Z
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.
Bigravity and Lorentz-violating massive gravity
Blas, D.; Garriga, J. [ICC, Departament de Fisica Fonamental, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain); Deffayet, C. [APC, Batiment Condorcet, 10 rue Alice Domont et Leonie Duquet, 75205 Paris Cedex 13 (France); GReCO/IAP, 98 bis Boulevard Arago, 75014 Paris (France)
2007-11-15T23:59:59.000Z
Bigravity is a natural arena where a nonlinear theory of massive gravity can be formulated. If the interaction between the metrics f and g is nonderivative, spherically symmetric exact solutions can be found. At large distances from the origin, these are generically Lorentz-breaking bi-flat solutions (provided that the corresponding vacuum energies are adjusted appropriately). The spectrum of linearized perturbations around such backgrounds contains a massless as well as a massive graviton, with two physical polarizations each. There are no propagating vectors or scalars, and the theory is ghost free (as happens with certain massive gravities with explicit breaking of Lorentz invariance). At the linearized level, corrections to general relativity are proportional to the square of the graviton mass, and so there is no van Dam-Veltam-Zakharov discontinuity. Surprisingly, the solution of linear theory for a static spherically symmetric source does not agree with the linearization of any of the known exact solutions. The latter coincide with the standard Schwarzschild-(anti)-de Sitter solutions of general relativity, with no corrections at all. Another interesting class of solutions is obtained where f and g are proportional to each other. The case of bi-de Sitter solutions is analyzed in some detail.
Canonical Quantum Gravity on Noncommutative Spacetime
Martin Kober
2014-09-04T23:59:59.000Z
In this paper canonical quantum gravity on noncommutative space-time is considered. The corresponding generalized classical theory is formulated by using the moyal star product, which enables the representation of the field quantities depending on noncommuting coordinates by generalized quantities depending on usual coordinates. But not only the classical theory has to be generalized in analogy to other field theories. Besides, the necessity arises to replace the commutator between the gravitational field operator and its canonical conjugated quantity by a corresponding generalized expression on noncommutative space-time. Accordingly the transition to the quantum theory has also to be performed in a generalized way and leads to extended representations of the quantum theoretical operators. If the generalized representations of the operators are inserted to the generalized constraints, one obtains the corresponding generalized quantum constraints including the Hamiltonian constraint as dynamical constraint. After considering quantum geometrodynamics under incorporation of a coupling to matter fields, the theory is transferred to the Ashtekar formalism. The holonomy representation of the gravitational field as it is used in loop quantum gravity opens the possibility to calculate the corresponding generalized area operator.
Optimization Online - Semi-definite relaxations for optimal control ...
Mathieu Claeys
2014-10-28T23:59:59.000Z
Oct 28, 2014 ... Abstract: Converging hierarchies of finite-dimensional semi-definite relaxations have been proposed for state-constrained optimal control ...
Modified definition of group velocity and electromagnetic energy conservation equation
Changbiao Wang
2015-01-19T23:59:59.000Z
The classical definition of group velocity has two flaws: (a) the group velocity can be greater than the phase velocity in a non-dispersive, lossless, non-conducting, anisotropic uniform medium; (b) the definition is not consistent with the principle of relativity for a plane wave in a moving isotropic uniform medium. To remove the flaws, a modified definition is proposed. A criterion is set up to identify the justification of group velocity definition. A "superluminal power flow" is constructed to show that the electromagnetic energy conservation equation cannot uniquely define the power flow if the principle of Fermat is not taken into account.
BLOCK DIAGONALLY DOMINANT POSITIVE DEFINITE APPROXIMATE FILTERS AND SMOOTHERS
BLOCK DIAGONALLY DOMINANT POSITIVE DEFINITE APPROXIMATE FILTERS AND SMOOTHERS Running title: BLOCKÆciently small as to preclude the loss of positive de#12;niteness in the approximate equations. Therefore
On the definition of velocity in doubly special relativity theories
Piotr Kosinski; Pawel Maslanka
2002-11-13T23:59:59.000Z
We discuss the definition of particle velocity in doubly relativity theories. The general formula relating velocity and four-momentum of particle is given.
Redundant axioms in the definition of Bregman functions
Jan 22, 2002 ... REDUNDANT AXIOMS IN THE DEFINITION OF BREGMAN ...... some new results on the theory of Bregman functions, Mathematics of ...
Genomic definition of species. Revision 2
Crkvenjakov, R.; Drmanac, R.
1993-03-01T23:59:59.000Z
A genome is the sum total of the DNA sequences in the cells of an individual organism. The common usage that species possess genomes comes naturally to biochemists, who have shown that all protein and nucleic acid molecules are at the same time species- and individual-specific, with minor individual variations being superimposed on a consensus sequence that is constant for a species. By extension, this property is attributed to the common features of DNA in the chromosomes of members of a given species and is called species genome. Our proposal for the definition of a biological species is as follows: A species comprises a group of actual and potential biological organisms built according to a unique genome program that is recorded, and at least in part expressed, in the structures of their genomic nucleic acid molecule(s), having intragroup sequence differences which can be fully interconverted in the process of organismal reproduction.
Li-E Qiang; Peng Xu
2015-02-16T23:59:59.000Z
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.
Qiang, Li-E
2015-01-01T23:59:59.000Z
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.
Aharon Davidson; Tomer Ygael
2014-10-22T23:59:59.000Z
A gravity-anti-gravity (GaG) odd linear dilaton action offers an eternal inflation evolution governed by the unified (cosmological constant plus radiation) equation of state $\\rho-3P=4\\Lambda$. At the mini superspace level, a 'two-particle' variant of the no-boundary proposal, notably 'one-particle' energy dependent, is encountered. While a GaG-odd wave function can only host a weak Big Bang boundary condition, albeit for any $k$, a strong Big Bang boundary condition requires a GaG-even entangled wave function, and singles out $k=0$ flat space. The locally most probable values for the cosmological scale factor and the dilaton field form a grid $\\{a^2,a\\phi\\}\\sim\\sqrt{4n_1+1}\\pm\\sqrt{4n_2+1}$.
Gauge/Gravity Duality and Strongly Coupled Light-Front Dynamics
de Teramond, Guy F.; /Costa Rica U.; Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins
2011-08-12T23:59:59.000Z
We find a correspondence between semiclassical gauge theories quantized on the light-front and a dual gravity model in anti-de Sitter (AdS) space, thus providing an initial approximation to QCD in its strongly coupled regime. This correspondence - light-front holography - leads to a light-front Hamiltonian and relativistic bound-state wave equations in terms of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron at equal light-front time. Light-front holography also allows a precise mapping of transition amplitudes from AdS to physical space-time. In contrast with the usual AdS/QCD framework, the internal structure of hadrons is explicitly introduced in the gauge/gravity correspondence and the angular momentum of the constituents plays a key role. We also discuss how to introduce higher Fock-states in the correspondence as well as their relevance for describing the detailed structure of space and time-like form factors.
Gauge/Gravity Duality and Hadron Physics at the Light-Front
Teramond, Guy F. de [Universidad de Costa Rica, San Jose (Costa Rica); Brodsky, Stanley J. [SLAC National Accelerator Laboratory, Stanford University, Stanford, California 94309, USA and CP3-Origins, University of Southern Denmark, Odense, 5230 M (Denmark)
2010-11-12T23:59:59.000Z
We discuss some remarkable features of the light-front holographic mapping of classical gravity in anti-de Sitter space modified by a confining dilaton background. In particular, we show that a positive-sign dilaton solution exp(+{kappa}{sup 2}z{sup 2}) has better chances to describe the correct hadronic phenomenology than the negative solution exp(-{kappa}{sup 2}z{sup 2}) extensively studied in the literature. We also show that the use of twist-scaling dimensions, instead of canonical dimensions, is required to give a good description of the spectrum and form factors of hadrons. Another key element is the explicit connection of AdS modes of total angular momentum J with the internal structure of hadrons and the proper identification of the orbital angular momentum of the constituents.
Solar system tests of Ho?ava-Lifshitz gravity
Tiberiu Harko; Zoltan Kovács; Francisco S. N. Lobo
2010-10-28T23:59:59.000Z
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.
Goedel-type universes in f(R) gravity
Reboucas, M. J. [Centro Brasileiro de Pesquisas Fisicas, Rua Dr. Xavier Sigaud 150, 22290-180 Rio de Janeiro-RJ (Brazil); Santos, J. [Universidade Federal do Rio G. do Norte, Departamento de Fisica, 59072-970 Natal-RN (Brazil)
2009-09-15T23:59:59.000Z
The f(R) gravity theories provide an alternative way to explain the current cosmic acceleration without a dark energy matter component. If gravity is governed by a f(R) theory, a number of issues should be reexamined in this framework, including the violation of causality problem on nonlocal scale. We examine the question as to whether the f(R) gravity theories permit space-times in which the causality is violated. We show that the field equations of these f(R) gravity theories do not exclude solutions with breakdown of causality for a physically well-motivated perfect-fluid matter content. We demonstrate that every perfect-fluid Goedel-type solution of a generic f(R) gravity satisfying the condition df/dR>0 is necessarily isometric to the Goedel geometry, and therefore presents violation of causality. This result extends a theorem on Goedel-type models, which has been established in the context of general relativity. We also derive an expression for the critical radius r{sub c} (beyond which the causality is violated) for an arbitrary f(R) theory, making apparent that the violation of causality depends on both the f(R) gravity theory and the matter content. As an illustration, we concretely take a recent f(R) gravity theory that is free from singularities of the Ricci scalar and is cosmologically viable, and show that this theory accommodates noncausal as well as causal Goedel-type solutions.
On the condensed matter scheme for emergent gravity and interferometry
G. Jannes
2008-11-10T23:59:59.000Z
An increasingly popular approach to quantum gravity rests on the idea that gravity (and maybe electromagnetism and the other gauge fields) might be an 'emergent phenomenon', in the sense of representing a collective behaviour resulting from a very different microscopic physics. A prominent example of this approach is the condensed matter scheme for quantum gravity, which considers the possibility that gravity emerges as an effective low-energy phenomenon from the quantum vacuum in a way similar to the emergence of collective excitations in condensed matter systems. This condensed matter view of the quantum vacuum clearly hints that, while the term 'ether' has been discredited for about a century, quantum gravity holds many (if not all) of the characteristics that have led people in the past to label various hypothetical substances with the term 'ether'. Since the last burst of enthusiasm for an ether, at the end of the 19th century, was brought to the grave in part by the performance of a series of important experiments in interferometry, the suggestion then naturally arises that maybe interferometry could also play a role in the current discussion on quantum gravity. We will highlight some aspects of this suggestion in the context of the condensed matter scheme for emergent gravity.
QKD with finite resources: secret key rates via Rényi entropies
Silvestre Abruzzo; Hermann Kampermann; Markus Mertz; Dagmar Bruß
2011-05-27T23:59:59.000Z
A realistic Quantum Key Distribution (QKD) protocol necessarily deals with finite resources, such as the number of signals exchanged by the two parties. We derive a bound on the secret key rate which is expressed as an optimization problem over R\\'enyi entropies. Under the assumption of collective attacks by an eavesdropper, a computable estimate of our bound for the six-state protocol is provided. This bound leads to improved key rates in comparison to previous results.
Security proof of practical quantum key distribution schemes
Yodai Watanabe
2005-06-29T23:59:59.000Z
This paper provides a security proof of the Bennett-Brassard (BB84) quantum key distribution protocol in practical implementation. To prove the security, it is not assumed that defects in the devices are absorbed into an adversary's attack. In fact, the only assumption in the proof is that the source is characterized. The proof is performed by lower-bounding adversary's Renyi entropy about the key before privacy amplification. The bound reveals the leading factors reducing the key generation rate.
Fake state attack on practically decoy state quantum key distribution
Yong-gang Tan
2012-02-15T23:59:59.000Z
In this paper, security of practically decoy state quantum key distribution under fake state attack is considered. If quantum key distribution is insecure under this type of attack, decoy sources can not also provide it with enough security. Strictly analysis shows that Eve should eavesdrop with the aid of photon-number-resolving instruments. In practical implementation of decoy state quantum key distribution where statistical fluctuation is considered, however, Eve can attack it successfully with threshold detectors.
Equivalence Relations Definition of a relation on a set
Singman, David
Equivalence Relations Definition of a relation on a set Let A be any set. Any subset have 1R1, 2R3, 3R1, 2 R2, 3 R2, etc. #12;A special kind of relation- an Equivalence relation There is a type of relation, it's known as an equivalence relation, which is particularly useful. Definition
EXTENDING THE DEFINITION OF ENTROPY TO NONEQUILIBRIUM STEADY STATES.
## of #. Our definition is based on energy exchanged, uses the microscopic dynamics of the system, and agreesEXTENDING THE DEFINITION OF ENTROPY TO NONEQUILIBRIUM STEADY STATES. by David Ruelle* Abstract. We forces # and maintained at fixed kinetic energy (HooverÂEvans isokinetic thermostat). We assume
Research Product 0-4186-P1 Definition of the
Texas at Austin, University of
Research Product 0-4186-P1 Definition of the "Cradle-to-Grave" Pavement Management Process Zhanmin in the definition given earlier, pavement management is in fact a process that starts from the conception-effective manner; it combines solid engi- neering principles with sound business practices and economic theory
1.0 Introduction 1.1 Definition of Nanotechnology
1 1.0 Introduction 1.1 Definition of Nanotechnology Nanotechnology is the art and science improvements in technologies for protecting the environment. While many definitions for nanotechnology exist Nanotechnology Initiative (NNI), a U.S. Government research and development (R&D) program established
Black Hole Thermodynamics in Modified Gravity
Jonas R. Mureika; John W. Moffat; Mir Faizal
2015-03-03T23:59:59.000Z
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.
Quantum Mechanics, Gravity, and the Multiverse
Yasunori Nomura
2012-07-30T23:59:59.000Z
The discovery of accelerating expansion of the universe has led us to take the dramatic view that our universe may be one of the many universes in which low energy physical laws take different forms: the multiverse. I explain why/how this view is supported both observationally and theoretically, especially by string theory and eternal inflation. I then describe how quantum mechanics plays a crucial role in understanding the multiverse, even at the largest distance scales. The resulting picture leads to a revolutionary change of our view of spacetime and gravity, and completely unifies the paradigm of the eternally inflating multiverse with the many worlds interpretation of quantum mechanics. The picture also provides a solution to a long-standing problem in eternal inflation, called the measure problem, which I briefly describe.
Kinetic Gravity Braiding and axion inflation
Debaprasad Maity
2013-03-11T23:59:59.000Z
We constructed a new class of inflationary model with the higher derivative axion field which obeys constant shift symmetry. In the usual axion (natural) inflation, the axion decay constant is predicted to be in the super-Planckian regime which is believed to be incompatible with an effective field theory framework. With a novel mechanism originating from a higher derivative kinetic gravity braiding (KGB) of an axion field we found that there exist a huge parameter regime in our model where axion decay constant could be naturally sub-Planckian. Thanks to the KGB which effectively reduces the Planck constant. This effectively reduced Planck scale provides us the mechanism of further lowering down the speed of an axion field rolling down its potential without introducing super-Planckian axion decay constant. We also find that with that wide range of parameter values, our model induces almost scale invariant power spectrum as observed in CMB experiments.
A length operator for canonical quantum gravity
T. Thiemann
1996-06-29T23:59:59.000Z
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.
Bi-metric Gravity and "Dark Matter"
I. T. Drummond
2000-08-18T23:59:59.000Z
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.
QCD thermodynamics using five-dimensional gravity
Megias, E.; Veschgini, K. [Institute for Theoretical Physics, University of Heidelberg (Germany); Pirner, H. J. [Institute for Theoretical Physics, University of Heidelberg (Germany); Max Planck Institute for Nuclear Physics, Heidelberg (Germany)
2011-03-01T23:59:59.000Z
We calculate the critical temperature and free energy of the gluon plasma using the dilaton potential [B. Galow, E. Megias, J. Nian, and H. J. Pirner, Nucl. Phys. B834, 330 (2010).] in the gravity theory of anti-de Sitter/QCD. The finite temperature observables are calculated in two ways: first, from the Page-Hawking computation of the free energy, and secondly using the Bekenstein-Hawking proportionality of the entropy with the area of the horizon. Renormalization is well defined, because the T=0 theory has asymptotic freedom. We further investigate the change of the critical temperature with the number of flavors induced by the change of the running coupling constant in the quenched theory. The finite temperature behavior of the speed of sound, spatial string tension and vacuum expectation value of the Polyakov loop follow from the corresponding string theory in AdS{sub 5}.
Bergshoeff, Eric A.; Hohm, Olaf [Centre for Theoretical Physics, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands); Townsend, Paul K. [Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)
2009-06-15T23:59:59.000Z
We explore the space of static solutions of the recently discovered three-dimensional 'new massive gravity' (NMG), allowing for either sign of the Einstein-Hilbert term and a cosmological term parametrized by a dimensionless constant {lambda}. For {lambda}=-1 we find black hole solutions asymptotic (but not isometric) to the unique (anti) de Sitter [(A)dS] vacuum, including extremal black holes that interpolate between this vacuum and (A)dS{sub 2}xS{sup 1}. We also investigate unitarity of linearized NMG in (A)dS vacua. We find unitary theories for some dS vacua, but (bulk) unitarity in AdS implies negative central charge of the dual conformal field theories (CFT), except for {lambda}=3 where the central charge vanishes and the bulk gravitons are replaced by 'massive photons'. A similar phenomenon is found in the massless limit of NMG, for which the linearized equations become equivalent to Maxwell's equations.
Gravity dual of metastable dynamical supersymmetry breaking
DeWolfe, Oliver [Department of Physics, 390 UCB, University of Colorado, Boulder, Colorado 80309 (United States); Kachru, Shamit; Mulligan, Michael [Department of Physics and SLAC, Stanford University, Stanford, California 94305/94309 (United States)
2008-03-15T23:59:59.000Z
Metastable, supersymmetry-breaking configurations can be created in flux geometries by placing antibranes in warped throats. Via gauge/gravity duality, such configurations should have an interpretation as supersymmetry-breaking states in the dual field theory. In this paper, we perturbatively determine the asymptotic supergravity solutions corresponding to D3-brane probes placed at the tip of the cascading warped deformed conifold geometry, which is dual to an SU(N+M)xSU(N) gauge theory. The backreaction of the antibranes has the effect of introducing imaginary anti-self-dual flux, squashing the compact part of the space and forcing the dilaton to run. Using the generalization of holographic renormalization to cascading geometries, we determine the expectation values of operators in the dual field theory in terms of the asymptotic values of the supergravity fields.
Brane f(R) gravity cosmologies
Balcerzak, Adam; DaPbrowski, Mariusz P. [Institute of Physics, University of Szczecin, Wielkopolska 15, 70-451 Szczecin (Poland)
2010-06-15T23:59:59.000Z
By the application of the generalized Israel junction conditions we derive cosmological equations for the fourth-order f(R) brane gravity and study their cosmological solutions. We show that there exists a nonstatic solution which describes a four-dimensional de Sitter (dS{sub 4}) brane embedded in a five-dimensional anti-de Sitter (AdS{sub 5}) bulk for a vanishing Weyl tensor contribution. On the other hand, for the case of a nonvanishing Weyl tensor contribution, there exists a static brane solution only. We claim that in order to get some more general nonstatic f(R) brane configurations, one needs to admit a dynamical matter energy-momentum tensor in the bulk rather than just a bulk cosmological constant.
Sandia Energy - Direct Measurement of Key Molecule Will Increase...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Direct Measurement of Key Molecule Will Increase Accuracy of Combustion Models Home Energy Transportation Energy CRF Facilities News News & Events Computational Modeling &...
Key Practical Issues in Strengthening Safety Culture, INSAG-15
Broader source: Energy.gov [DOE]
Key Pratical Issues in Strengthening Safety Culture, INSAG-15. A report by the International Nuclear Safety Advisory Gorup, International Atomic Energy Agency, Vienna, 2002.
MasterKey Cryptosystems AT&T Bell Labs
Blaze, Matthew
then be converted to a stream cipher via one of the usual blockchaining methods). We use the publickey encryption
Pantex Plant Achieves Key Safety Milestone Ahead of Schedule...
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Achieves Key Safety Milestone Ahead of Schedule | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing...
Key Parameters Affecting DPF Performance Degradation and Impact...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Parameters Affecting DPF Performance Degradation and Impact on Lifetime Fuel Economy Key Parameters Affecting DPF Performance Degradation and Impact on Lifetime Fuel Economy...
Sierra Geothermal's Key Find in Southern Nevada | Department...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Geothermal's Key Find in Southern Nevada July 13, 2010 - 5:17pm Addthis Sierra Geothermal discovered temperatures hot enough for large-scale geothermal energy production at...
Climate Action Planning: A Review of Best Practices, Key Elements...
Planning: A Review of Best Practices, Key Elements, and Common Climate Strategies for Signatories to the American College & University Presidents' Climate Commitment Jump to:...
Key Facts about the Biosciences Division | Argonne National Laboratory
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
to understand biological mechanisms relevant to bioremediation, climate change, energy production, and the protection of human health. BiosciencesDivisionKeyFactsOct20...
Water dynamics clue to key residues in protein folding
Gao, Meng [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China)] [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China); Zhu, Huaiqiu, E-mail: hqzhu@pku.edu.cn [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China)] [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China); Yao, Xin-Qiu [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China) [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China); Department of Biophysics, Kyoto University, Sakyo Kyoto 606-8502 (Japan); She, Zhen-Su, E-mail: she@pku.edu.cn [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China)] [State Key Laboratory for Turbulence and Complex Systems, and Department of Biomedical Engineering, and Center for Theoretical Biology, and Center for Protein Science, Peking University, Beijing 100871 (China)
2010-01-29T23:59:59.000Z
A computational method independent of experimental protein structure information is proposed to recognize key residues in protein folding, from the study of hydration water dynamics. Based on all-atom molecular dynamics simulation, two key residues are recognized with distinct water dynamical behavior in a folding process of the Trp-cage protein. The identified key residues are shown to play an essential role in both 3D structure and hydrophobic-induced collapse. With observations on hydration water dynamics around key residues, a dynamical pathway of folding can be interpreted.
Worldwide Trends in Energy Use and Efficiency: Key Insights from...
Efficiency: Key Insights from International Energy Agency (IEA) Indicator Analysis in Support of the Group of Eight (G8) Plan of Action Jump to: navigation, search Tool Summary...
PPPL physicists win supercomputing time to simulate key energy...
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PPPL physicists win supercomputing time to simulate key energy and astrophysical phenomena By John Greenwald January 8, 2013 Tweet Widget Google Plus One Share on Facebook A...
The dynamics of metric-affine gravity
Vitagliano, Vincenzo, E-mail: vitaglia@sissa.it [SISSA-International School for Advanced Studies, Via Bonomea 265, 34136 Trieste (Italy); INFN, Sez. di Trieste, Via Valerio 2, 34127 Trieste (Italy); Sotiriou, Thomas P., E-mail: T.Sotiriou@damtp.cam.ac.uk [Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom); Liberati, Stefano, E-mail: liberati@sissa.it [SISSA-International School for Advanced Studies, Via Bonomea 265, 34136 Trieste (Italy); INFN, Sez. di Trieste, Via Valerio 2, 34127 Trieste (Italy)
2011-05-15T23:59:59.000Z
Highlights: > The role and the dynamics of the connection in metric-affine theories is explored. > The most general second order action does not lead to a dynamical connection. > Including higher order invariants excites new degrees of freedom in the connection. > f(R) actions are also discussed and shown to be a non- representative class. - Abstract: Metric-affine theories of gravity provide an interesting alternative to general relativity: in such an approach, the metric and the affine (not necessarily symmetric) connection are independent quantities. Furthermore, the action should include covariant derivatives of the matter fields, with the covariant derivative naturally defined using the independent connection. As a result, in metric-affine theories a direct coupling involving matter and connection is also present. The role and the dynamics of the connection in such theories is explored. We employ power counting in order to construct the action and search for the minimal requirements it should satisfy for the connection to be dynamical. We find that for the most general action containing lower order invariants of the curvature and the torsion the independent connection does not carry any dynamics. It actually reduces to the role of an auxiliary field and can be completely eliminated algebraically in favour of the metric and the matter field, introducing extra interactions with respect to general relativity. However, we also show that including higher order terms in the action radically changes this picture and excites new degrees of freedom in the connection, making it (or parts of it) dynamical. Constructing actions that constitute exceptions to this rule requires significant fine tuned and/or extra a priori constraints on the connection. We also consider f(R) actions as a particular example in order to show that they constitute a distinct class of metric-affine theories with special properties, and as such they cannot be used as representative toy theories to study the properties of metric-affine gravity.
Simulations of Solar System observations in alternative theories of gravity
A. Hees; B. Lamine; S. Reynaud; M. -T. Jaekel; C. Le Poncin-Lafitte; V. Lainey; A. Füzfa; J. -M. Courty; V. Dehant; P. Wolf
2013-02-27T23:59:59.000Z
In this communication, we focus on the possibility to test General Relativity (GR) with radioscience experiments. We present simulations of observables performed in alternative theories of gravity using a software that simulates Range/Doppler signals directly from the space time metric. This software allows one to get the order of magnitude and the signature of the modifications induced by an alternative theory of gravity on radioscience signals. As examples, we present some simulations for the Cassini mission in Post-Einsteinian gravity (PEG) and with Standard Model Extension (SME).
Particles on a Circle in Canonical Lineal Gravity
R. B. Mann
2001-05-02T23:59:59.000Z
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.
Emergent noncommutative gravity from a consistent deformation of gauge theory
Cortese, Ignacio; Garcia, J Antonio [Departamento de Fisica de Altas Energias, Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, Mexico D. F. 04510 (Mexico)
2010-05-15T23:59:59.000Z
Starting from a standard noncommutative gauge theory and using the Seiberg-Witten map, we propose a new version of a noncommutative gravity. We use consistent deformation theory starting from a free gauge action and gauging a killing symmetry of the background metric to construct a deformation of the gauge theory that we can relate with gravity. The result of this consistent deformation of the gauge theory is nonpolynomial in A{sub {mu}.} From here we can construct a version of noncommutative gravity that is simpler than previous attempts. Our proposal is consistent and is not plagued with the problems of other approaches like twist symmetries or gauging other groups.
Ground Gravity Survey At Under Steamboat Springs Area (Warpinski...
Notes Update to Warpinski, et al., 2002 References N. R. Warpinski, A. R. Sattler, R. Fortuna, D. A. Sanchez, J. Nathwani (2004) Geothermal Resource Exploration And Definition...
Lozano-Robledo, Alvaro
Formulas & definitions to know Formulas & definitions that will be provided if needed Distance formula in 3 dimensions compab = aÂ·b |a| Equation of a sphere W = F Â· D (work, force, distance) Vector of differentiability for a function of two variables arc length formula, arc length function the graph of a function
Hendi, Seyed Hossein; Panah, Behzad Eslam
2015-01-01T23:59:59.000Z
In this paper, we are considering two first order corrections to both gravity and gauge sides of the Einstein-Maxwell gravity: Gauss-Bonnet gravity and quadratic Maxwell invariant as corrections. We obtain horizonless magnetic solutions by implying a metric which representing a topological defect. We analyze the geometric properties of the solutions and investigate the effects of both corrections, and find that these solutions may be interpreted as the magnetic branes. We study the singularity condition and find a nonsingular spacetime with a conical geometry. We also investigate the effects of different parameters on deficit angle of spacetime near the origin.
Mind Your Manners: Socially Appropriate Wireless Key Establishment for Groups
Xu, Wenyuan
group key establish- ment. We identify seven social and situational factors which impact group formationMind Your Manners: Socially Appropriate Wireless Key Establishment for Groups Cynthia Kuo Ahren Studer Adrian Perrig Carnegie Mellon University {cykuo, astuder, perrig}@cmu.edu ABSTRACT Group
Public Key Encryption that Allows PIR Queries Eyal Kushilevitz
Public Key Encryption that Allows PIR Queries Dan Boneh Eyal Kushilevitz Rafail Ostrovsky William E to create a public- key encryption scheme for Alice that allows PIR searching over encrypted documents. Our allows for Single-Database PIR writing with sublinear communication complexity, which we consider
Public Key Encryption that Allows PIR Queries Eyal Kushilevitz
Ostrovsky, Rafail
Public Key Encryption that Allows PIR Queries Dan Boneh Eyal Kushilevitz Rafail Ostrovsky William E. In this paper, we show how to create a public-key encryption scheme for Alice that allows PIR searching over allows for Single-Database PIR writing with sublinear communication complexity, which we consider
Key ornamental innovations facilitate diversification in an avian radiation
Rubenstein, Dustin R.
Key ornamental innovations facilitate diversification in an avian radiation Rafael Maiaa,1 , Dustin novel ways of interacting with the en- vironment (key innovations) play a fundamental role in promoting evolution of orna- mental traits. Because selection can operate only on existing vari- ation, the tendency
Energy Security: A Key Requirement forSustainable Development
1 Energy Security: A Key Requirement forSustainable Development Perspective and Action Plan Robert Card Under Secretary US Department of Energy August 30, 2002 Session One: Maintaining Energy Security WSSD Side Event Energy for Sustainable Development IEA/UNEP/Eskom #12;2 Energy Security is a Key
Reflective cracking of shear keys in multi-beam bridges
Sharpe, Graeme Peter
2009-06-02T23:59:59.000Z
..............................................2 Figure 2: PCI 33? Box Girder with Shear Keys................................................................5 Figure 3: TxDOT 34? Box Girder with Shear Keys .........................................................5 Figure 4: Test Specimen... Under Tension.........................................................................12 Figure 5: Test Specimen in Bending ...............................................................................12 Figure 6: Test Specimen in Shear...
USB KEY PROFILE MANAGER FOR MOZILLA A Project Report
Pollett, Chris
USB KEY PROFILE MANAGER FOR MOZILLA A Project Report Presented to The Faculty of the Department FOR THE UNIVERSITY _____________________________________________________ 3 #12;ABSTRACT USB KEY PROFILE MANAGER FOR MOZILLA By Yun Zhou Mozilla's profile manager allows users to save their private information
Secret-Key Generation using Correlated Sources and Channels
Khisti, Ashish
1 Secret-Key Generation using Correlated Sources and Channels Ashish Khisti, Member, IEEE of generating a shared secret key between two terminals in a joint source-channel setup -- the terminals to correlated discrete memoryless source sequences. We establish lower and upper bounds on the secret
Hybrid Secret Key Escrow Mechanisms as Counters Esa Hyytia
Hyytiä, Esa
Hybrid Secret Key Escrow Mechanisms as Counters Esa Hyyti¨a Telecommunications Research Center can be used in several ways. One interesting application of the Shamir's secret sharing scheme in the context of privacy aware traffic monitoring is to escrow a secret key after m suspicious events have been
accident conditions key: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
accident conditions key First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Range Condition: Key to...
The evolution of miscible gravity currents in horizontal porous layers
Szulczewski, Michael Lawrence
Gravity currents of miscible fluids in porous media are important to understand because they occur in important engineering projects, such as enhanced oil recovery and geologic CO[subscript 2] sequestration. These flows ...
Dust-shell Universe in the modified gravity scenario
Michael Maziashvili
2005-04-15T23:59:59.000Z
The dynamics of the dust-shell model of universe is exactly solved for the modified Schwarzschild solution. This solution is used to derive the cosmology corresponding to the modified gravity.
Ground Gravity Survey At Neal Hot Springs Geothermal Area (U...
Hot Springs. Data from these surveys will be integrated with older data from Chevron Minerals 1979 drill hole. Notes The gravity survey covered an area of approximately 34 km2...
Horava-Lifshitz Gravity From Dynamical Newton-Cartan Geometry
Hartong, Jelle
2015-01-01T23:59:59.000Z
Recently it has been established that torsional Newton-Cartan (TNC) geometry is the appropriate geometrical framework to which non-relativistic field theories couple. We show that when these geometries are made dynamical they give rise to Horava-Lifshitz (HL) gravity. Projectable HL gravity corresponds to dynamical Newton-Cartan (NC) geometry without torsion and non-projectable HL gravity corresponds to dynamical NC geometry with twistless torsion (hypersurface orthogonal foliation). We build a precise dictionary relating all fields (including the scalar khronon), their transformations and other properties in both HL gravity and dynamical TNC geometry. We use TNC invariance to construct the effective action for dynamical twistless torsional Newton-Cartan geometries in 2+1 dimensions for dynamical exponent 1
Ground Gravity Survey At Mt Princeton Hot Springs Geothermal...
Notes Gravity low associated with Mt. Princeton Batholith; density contrast of -0.5 gcm3 of valley-fill sediments relative to batholith References J.E. Case, R.F. Sikora...
Ground Gravity Survey At Dixie Valley Geothermal Area (Iovenitti...
project area. These data were used in conjunction with past gravity data reported in by Smith et al (2001) and Blackwell et al (2005). The analysis of these data had not been...
Mixed convection and heat management in the Mars gravity biosatellite
Marsh, Jesse B. (Jesse Benjamin)
2007-01-01T23:59:59.000Z
The Mars Gravity Biosatellite will house fifteen mice in a low Earth orbit satellite spinning about its longitudinal axis. The satellite's payload thermal control system will reject heat through the base of the payload ...
Hyperbolic Equations for Vacuum Gravity Using Special Orthonormal Frames
Frank B. Estabrook; R. Steve Robinson; Hugo D. Wahlquist
2004-09-29T23:59:59.000Z
By adopting Nester's higher dimensional special orthonormal frames (HSOF) the tetrad equations for vacuum gravity are put into first order symmetric hyperbolic (FOSH) form with constant coefficients, independent of any time slicing or coordinate specialization.
Regional Gravity Survey of the Northern Great Salt Lake Desert...
Northern Great Salt Lake Desert and Adjacent Areas in Utah, Nevada, and Idaho Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Regional Gravity...
Quantized gauge-affine gravity in the superfiber bundle approach
Meziane, A.; Tahiri, M. [Laboratoire de Physique Theorique, Universite d'Oran Es-senia, 31100 Oran (Algeria)
2005-05-15T23:59:59.000Z
The quantization of gauge-affine gravity within the superfiber bundle formalism is proposed. By introducing an even pseudotensorial 1-superform over a principal superfiber 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 GA(4,R) to the Poincare group double-covering ISO(1,3) 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.
Status of Matter-Gravity Couplings in the SME
Tasson, Jay D
2013-01-01T23:59:59.000Z
Constraints on Lorentz violation in matter-gravity couplings are summarized along with existing proposals to obtain sensitivities that exceed current limits by up to 11 orders of magnitude.