Journal•ISSN: 0556-2821

# Physical Review D

American Physical Society

About: Physical Review D is an academic journal. The journal publishes majorly in the area(s): Quantum chromodynamics & Quark. Over the lifetime, 96249 publications have been published receiving 3791277 citations.

Topics: Quantum chromodynamics, Quark, Black hole, Neutrino, Gauge theory

##### Papers published on a yearly basis

##### Papers

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TL;DR: In this paper, the authors proposed a model of hot big-bang cosmology where the early universe is assumed to be highly homogeneous, in spite of the fact that separated regions were causally disconnected (horizon problem).

Abstract: The standard model of hot big-bang cosmology requires initial conditions which are problematic in two ways: (1) The early universe is assumed to be highly homogeneous, in spite of the fact that separated regions were causally disconnected (horizon problem); and (2) the initial value of the Hubble constant must be fine tuned to extraordinary accuracy to produce a universe as flat (i.e., near critical mass density) as the one we see today (flatness problem). These problems would disappear if, in its early history, the universe supercooled to temperatures 28 or more orders of magnitude below the critical temperature for some phase transition. A huge expansion factor would then result from a period of exponential growth, and the entropy of the universe would be multiplied by a huge factor when the latent heat is released. Such a scenario is completely natural in the context of grand unified models of elementary-particle interactions. In such models, the supercooling is also relevant to the problem of monopole suppression. Unfortunately, the scenario seems to lead to some unacceptable consequences, so modifications must be sought.

8,758 citations

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TL;DR: In this paper, the concept of black-hole entropy was introduced as a measure of information about a black hole interior which is inaccessible to an exterior observer, and it was shown that the entropy is equal to the ratio of the black hole area to the square of the Planck length times a dimensionless constant of order unity.

Abstract: There are a number of similarities between black-hole physics and thermodynamics. Most striking is the similarity in the behaviors of black-hole area and of entropy: Both quantities tend to increase irreversibly. In this paper we make this similarity the basis of a thermodynamic approach to black-hole physics. After a brief review of the elements of the theory of information, we discuss black-hole physics from the point of view of information theory. We show that it is natural to introduce the concept of black-hole entropy as the measure of information about a black-hole interior which is inaccessible to an exterior observer. Considerations of simplicity and consistency, and dimensional arguments indicate that the black-hole entropy is equal to the ratio of the black-hole area to the square of the Planck length times a dimensionless constant of order unity. A different approach making use of the specific properties of Kerr black holes and of concepts from information theory leads to the same conclusion, and suggests a definite value for the constant. The physical content of the concept of black-hole entropy derives from the following generalized version of the second law: When common entropy goes down a black hole, the common entropy in the black-hole exterior plus the black-hole entropy never decreases. The validity of this version of the second law is supported by an argument from information theory as well as by several examples.

6,591 citations

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TL;DR: The complete review as discussed by the authors is published online on the website of the Particle Data Group (http://pdg.lbl.gov) and in a journal. Volume 1 is available in print as thePDG Book.

Abstract: The complete Review(both volumes) is published online on the website of the Particle Data Group(http://pdg.lbl.gov) and in a journal. Volume 1 is available in print as thePDG Book. AParticle Physics Bookletwith the Summary Tables and essential tables, figures, and equations from selected review articles is also available.

6,464 citations

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TL;DR: In this article, the Boltzmann formula for lower temperatures has been developed for a correction term, which can be developed into a power series of h. The formula is developed for this correction by means of a probability function and the result discussed.

Abstract: The probability of a configuration is given in classical theory by the Boltzmann formula exp [— V/hT] where V is the potential energy of this configuration. For high temperatures this of course also holds in quantum theory. For lower temperatures, however, a correction term has to be introduced, which can be developed into a power series of h. The formula is developed for this correction by means of a probability function and the result discussed.

5,865 citations

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Tohoku University

^{1}, University of Zurich^{2}, Lawrence Berkeley National Laboratory^{3}, Stanford University^{4}, College of William & Mary^{5}, University of Urbino^{6}, CERN^{7}, Budker Institute of Nuclear Physics^{8}, University of California, Irvine^{9}, Cornell University^{10}, Argonne National Laboratory^{11}, ETH Zurich^{12}, Tata Institute of Fundamental Research^{13}, Hillsdale College^{14}, Spanish National Research Council^{15}, Ohio State University^{16}, University of Notre Dame^{17}, Kent State University^{18}, University of California, San Diego^{19}, University of California, Berkeley^{20}, University of Minnesota^{21}, University of Alabama^{22}, University of Helsinki^{23}, Los Alamos National Laboratory^{24}, California Institute of Technology^{25}, George Washington University^{26}, Syracuse University^{27}, Lawrence Livermore National Laboratory^{28}, Oklahoma State University–Stillwater^{29}, University of Washington^{30}, Max Planck Society^{31}, Boston University^{32}, University of California, Los Angeles^{33}, Royal Holloway, University of London^{34}, Université Paris-Saclay^{35}, University of Pennsylvania^{36}, University of Illinois at Urbana–Champaign^{37}, University of Bristol^{38}, University of Tokyo^{39}, University of Delaware^{40}, Carnegie Mellon University^{41}, University of California, Santa Cruz^{42}, Karlsruhe Institute of Technology^{43}, Heidelberg University^{44}, Florida State University^{45}, University of Mainz^{46}, University of Edinburgh^{47}, Brookhaven National Laboratory^{48}, Durham University^{49}, University of Lausanne^{50}, Massachusetts Institute of Technology^{51}, University of Southampton^{52}, Nagoya University^{53}, University of Oxford^{54}, Northwestern University^{55}, University of British Columbia^{56}, Columbia University^{57}, Lund University^{58}, University of Sheffield^{59}, University of California, Santa Barbara^{60}, Iowa State University^{61}, University of Alberta^{62}, University of Cambridge^{63}TL;DR: This biennial Review summarizes much of Particle Physics using data from previous editions, plus 2205 new measurements from 667 papers, and features expanded coverage of CP violation in B mesons and of neutrino oscillations.

Abstract: This biennial Review summarizes much of Particle Physics. Using data from previous editions, plus 2205 new measurements from 667 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. This edition features expanded coverage of CP violation in B mesons and of neutrino oscillations. For the first time we cover searches for evidence of extra dimensions (both in the particle listings and in a new review). Another new review is on Grand Unified Theories. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http://pdg.lbl.gov.

5,143 citations