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Title: Thermodynamical interpretation of gravity in braneworld scenarios

Abstract

We study the thermodynamical properties of the apparent horizon in the various braneworld scenarios. First, we show that the Friedmann equations can be written directly in the form of the first law of thermodynamics, dE = T{sub h}dS{sub h}+WdV, at apparent horizon on the brane, regardless of whether there is the intrinsic curvature term on the brane or a Gauss-Bonnet term in the bulk. This procedure leads to extract an entropy expression in terms of horizon geometry associated with the apparent horizon. Then, we examine the time evolution of the total entropy, including the derived entropy of the apparent horizon and the entropy of the matter fields inside the apparent horizon. We find that the derived entropy of the apparent horizon on the brane satisfies the generalized second law of thermodynamics in braneworld scenarios. These results further support the idea that gravitation on a macroscopic scale is a manifestation of thermodynamics.

Authors:
 [1]
  1. Department of Physics, Shahid Bahonar University, P.O. Box 76175, Kerman (Iran, Islamic Republic of)
Publication Date:
OSTI Identifier:
22157001
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2009; Journal Issue: 05; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BRANES; ENTROPY; GALACTIC EVOLUTION; GEOMETRY; GRAVITATION; M-THEORY; THERMODYNAMICS

Citation Formats

Sheykhi, Ahmad, E-mail: sheykhi@mail.uk.ac.ir. Thermodynamical interpretation of gravity in braneworld scenarios. United States: N. p., 2009. Web. doi:10.1088/1475-7516/2009/05/019.
Sheykhi, Ahmad, E-mail: sheykhi@mail.uk.ac.ir. Thermodynamical interpretation of gravity in braneworld scenarios. United States. doi:10.1088/1475-7516/2009/05/019.
Sheykhi, Ahmad, E-mail: sheykhi@mail.uk.ac.ir. 2009. "Thermodynamical interpretation of gravity in braneworld scenarios". United States. doi:10.1088/1475-7516/2009/05/019.
@article{osti_22157001,
title = {Thermodynamical interpretation of gravity in braneworld scenarios},
author = {Sheykhi, Ahmad, E-mail: sheykhi@mail.uk.ac.ir},
abstractNote = {We study the thermodynamical properties of the apparent horizon in the various braneworld scenarios. First, we show that the Friedmann equations can be written directly in the form of the first law of thermodynamics, dE = T{sub h}dS{sub h}+WdV, at apparent horizon on the brane, regardless of whether there is the intrinsic curvature term on the brane or a Gauss-Bonnet term in the bulk. This procedure leads to extract an entropy expression in terms of horizon geometry associated with the apparent horizon. Then, we examine the time evolution of the total entropy, including the derived entropy of the apparent horizon and the entropy of the matter fields inside the apparent horizon. We find that the derived entropy of the apparent horizon on the brane satisfies the generalized second law of thermodynamics in braneworld scenarios. These results further support the idea that gravitation on a macroscopic scale is a manifestation of thermodynamics.},
doi = {10.1088/1475-7516/2009/05/019},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2009,
place = {United States},
year = 2009,
month = 5
}
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