2,212 research outputs found
Holographic Quantum Statistics from Dual Thermodynamics
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
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
ray line generated by the Green-Schwarz mechanism
We study the phenomenology of a 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 , 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
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 MeV gamma radiation from
decays.Comment: 4 pages, 1 figur
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