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Title: Corrected entropy of Friedmann-Robertson-Walker universe in tunneling method

Abstract

In this paper, we study the thermodynamic quantities of Friedmann-Robertson-Walker (FRW) universe by using the tunneling formalism beyond semiclassical approximation developed by Banerjee and Majhi [25]. For this we first calculate the corrected Hawking-like temperature on apparent horizon by considering both scalar particle and fermion tunneling. With this corrected Hawking-like temperature, the explicit expressions of the corrected entropy of apparent horizon for various gravity theories including Einstein gravity, Gauss-Bonnet gravity, Lovelock gravity, f(R) gravity and scalar-tensor gravity, are computed. Our results show that the corrected entropy formula for different gravity theories can be written into a general expression (4.39) of a same form. It is also shown that this expression is also valid for black holes. This might imply that the expression for the corrected entropy derived from tunneling method is independent of gravity theory, spacetime and dimension of the spacetime. Moreover, it is concluded that the basic thermodynamical property that the corrected entropy on apparent horizon is a state function is satisfied by the FRW universe.

Authors:
; ;  [1]
  1. Institute of Theoretical Physics, Lanzhou University, Lanzhou 730000 (China)
Publication Date:
OSTI Identifier:
22273218
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2009; Journal Issue: 08; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BLACK HOLES; COSMOLOGICAL MODELS; COSMOLOGY; ENTROPY; FERMIONS; GRAVITATION; SCALARS; SEMICLASSICAL APPROXIMATION; SPACE-TIME; TENSORS; THERMODYNAMICS; TUNNEL EFFECT; UNIVERSE

Citation Formats

Zhu, Tao, Ren, Ji-Rong, and Li, Ming-Fan, E-mail: zhut05@lzu.cn, E-mail: renjr@lzu.edu.cn, E-mail: limf07@lzu.cn. Corrected entropy of Friedmann-Robertson-Walker universe in tunneling method. United States: N. p., 2009. Web. doi:10.1088/1475-7516/2009/08/010.
Zhu, Tao, Ren, Ji-Rong, & Li, Ming-Fan, E-mail: zhut05@lzu.cn, E-mail: renjr@lzu.edu.cn, E-mail: limf07@lzu.cn. Corrected entropy of Friedmann-Robertson-Walker universe in tunneling method. United States. doi:10.1088/1475-7516/2009/08/010.
Zhu, Tao, Ren, Ji-Rong, and Li, Ming-Fan, E-mail: zhut05@lzu.cn, E-mail: renjr@lzu.edu.cn, E-mail: limf07@lzu.cn. 2009. "Corrected entropy of Friedmann-Robertson-Walker universe in tunneling method". United States. doi:10.1088/1475-7516/2009/08/010.
@article{osti_22273218,
title = {Corrected entropy of Friedmann-Robertson-Walker universe in tunneling method},
author = {Zhu, Tao and Ren, Ji-Rong and Li, Ming-Fan, E-mail: zhut05@lzu.cn, E-mail: renjr@lzu.edu.cn, E-mail: limf07@lzu.cn},
abstractNote = {In this paper, we study the thermodynamic quantities of Friedmann-Robertson-Walker (FRW) universe by using the tunneling formalism beyond semiclassical approximation developed by Banerjee and Majhi [25]. For this we first calculate the corrected Hawking-like temperature on apparent horizon by considering both scalar particle and fermion tunneling. With this corrected Hawking-like temperature, the explicit expressions of the corrected entropy of apparent horizon for various gravity theories including Einstein gravity, Gauss-Bonnet gravity, Lovelock gravity, f(R) gravity and scalar-tensor gravity, are computed. Our results show that the corrected entropy formula for different gravity theories can be written into a general expression (4.39) of a same form. It is also shown that this expression is also valid for black holes. This might imply that the expression for the corrected entropy derived from tunneling method is independent of gravity theory, spacetime and dimension of the spacetime. Moreover, it is concluded that the basic thermodynamical property that the corrected entropy on apparent horizon is a state function is satisfied by the FRW universe.},
doi = {10.1088/1475-7516/2009/08/010},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 08,
volume = 2009,
place = {United States},
year = 2009,
month = 8
}
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