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arXiv · 1009.2941

Cosmological entropy and generalized second law of thermodynamics in $F(R,G)$ theory of gravity

H. Mohseni Sadjadi
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Abstract

We consider a spatially flat Friedmann-Lemaitre-Robertson-Walker space time and investigate the second law and the generalized second law of thermodynamics for apparent horizon in generalized modified Gauss Bonnet theory of gravity (whose action contains a general function of Gauss Bonnet invariant and the Ricci scalar: $F(R,G)$). By assuming that the apparent horizon is in thermal equilibrium with the matter inside it, conditions which must be satisfied by $F(R,G)$ are derived and elucidated through two examples: a quasi-de Sitter space-time and a universe with power law expansion.

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H. Mohseni Sadjadi. 2010-12-27. Cosmological entropy and generalized second law of thermodynamics in $F(R,G)$ theory of gravity. https://doi.org/10.1209/0295-5075%2F92%2F50014

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