2,212 research outputs found

    Holographic Quantum Statistics from Dual Thermodynamics

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    We propose dual thermodynamics corresponding to black hole mechanics with the identifications E' -> A/4, S' -> M, and T' -> 1/T in Planck units. Here A, M and T are the horizon area, mass and Hawking temperature of a black hole and E', S' and T' are the energy, entropy and temperature of a corresponding dual quantum system. We show that, for a Schwarzschild black hole, the dual variables formally satisfy all three laws of thermodynamics, including the Planck-Nernst form of the third law requiring that the entropy tend to zero at low temperature. This is in contrast with traditional black hole thermodynamics, where the entropy is singular. Once the third law is satisfied, it is straightforward to construct simple (dual) quantum systems representing black hole mechanics. As an example, we construct toy models from one dimensional (Fermi or Bose) quantum gases with N ~ M in a Planck scale box. In addition to recovering black hole mechanics, we obtain quantum corrections to the entropy, including the logarithmic correction obtained by previous papers. The energy-entropy duality transforms a strongly interacting gravitational system (black hole) into a weakly interacting quantum system (quantum gas) and thus provides a natural framework for the quantum statistics underlying the holographic conjecture.Comment: 10 page

    Relic density of neutralinos in minimal supergravity

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    We evaluate the relic density of neutralinos in the minimal supergravity (mSUGRA) model. All 2->2 neutralino annihilation diagrams, as well as all initial states involving sleptons, charginos, neutralinos and third generation squarks are included. Relativistic thermal averaging of the velocity times cross sections is performed. We find that co-annihilation effects are only important on the edges of the model parameter space, where some amount of fine-tuning is necessary to obtain a reasonable relic density. Alternatively, at high tan(beta), annihilation through the broad Higgs resonances gives rise to an acceptable neutralino relic density over broad regions of parameter space where little or no fine-tuning is needed.Comment: LaTeX, 10 pages. Talk given by Alexander Belyaev at SUSY'02, "The 10th International Conference on Supersymmetry and Unification of Fundamental Interactions", DESY, Hamburg, Germany, 17-23 June 200

    γ−\gamma-ray line generated by the Green-Schwarz mechanism

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    We study the phenomenology of a UX(1)U_X(1) extension of the Standard Model where the SM particles are not charged under the new abelian group. The Green-Schwarz mechanism insures that the model is anomaly free. The erstwhile invisible dark gauge field XX, even if produced with difficulty at the LHC has however a clear signature in gamma-ray telescopes. We investigate what BSM scale (which can be interpreted as a low-energy string scale) would be reachable by the FERMI/GLAST telescope after 5 years of running and show that a 1 TeV scale can be testable, which is highly competitive with the LHC.Comment: Proceedings of DSU09 "The Dark Side of the Universe", 1-5 June 2009, Melbourne, 6 pages, 2 figure

    On Stimulated Radiation of Black Holes

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    The Unruh's thermal state in the vicinity of the event horizon of the black hole provides conditions where impinging particles can radiate other particles. The subsequent decays may eventually lead to observable radiation of photons and neutrinos induced even by massive particles with gravitational interaction only. The hadronic particles will induce ∼30\sim 30 MeV gamma radiation from π0\pi^{0} decays.Comment: 4 pages, 1 figur
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