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Related papers: Thermodynamics in $f(R)$ gravity in the Palatini f…

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We explore thermodynamics of the apparent horizon in $f(T)$ gravity with both equilibrium and non-equilibrium descriptions. We find the same dual equilibrium/non-equilibrium formulation for $f(T)$ as for $f(R)$ gravity. In particular, we…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Kazuharu Bamba , Chao-Qiang Geng

We study thermodynamics of the apparent horizon in $F(R)$ gravity. In particular, we demonstrate that a $F(R)$ gravity model with realizing a crossing of the phantom divide can satisfy the second law of thermodynamics in the effective…

High Energy Physics - Theory · Physics 2009-09-28 Kazuharu Bamba , Chao-Qiang Geng

In this paper we discuss the thermodynamics of the apparent horizon in $F(R)$ Ho\v{r}ava-Lifshitz gravity in equilibrium and non-equilibrium ensembles. We show that the second law of thermodynamics can be satisfied in this non relativistic…

General Relativity and Quantum Cosmology · Physics 2016-02-22 Abdul Jawad , Shamaila Rani , Davood Momeni , Faiza Gulshan , Ratbay Myrzakulov

In the present paper, we study the thermodynamics behavior of the field equations for the generalized f(T) gravity with an arbitrary coupling between matter and the torsion scalar. In this regard, we explore the verification of the first…

General Relativity and Quantum Cosmology · Physics 2017-01-17 Tahereh Azizi , Najibeh Borhani

In an accelerated expanding universe, one can expect the existence of an event horizon. It may be interesting to study the thermodynamics of the Friedmann-Robertson-Walker (FRW) universe at the event horizon. Considering the usual Hawking…

General Relativity and Quantum Cosmology · Physics 2018-11-06 A. S. Sefiedgar , M. Mirzazadeh

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…

General Relativity and Quantum Cosmology · Physics 2011-01-17 H. Mohseni Sadjadi

We demonstrate that there does exist an equilibrium description of thermodynamics on the apparent horizon in the expanding cosmological background for a wide class of modified gravity theories with the Lagrangian density $f(R, \phi, X)$,…

General Relativity and Quantum Cosmology · Physics 2011-08-05 Kazuharu Bamba , Chao-Qiang Geng , Shinji Tsujikawa

We investigate the thermodynamical properties of the apparent horizon in a fractal universe. We find that one can always rewrite the Friedmann equation of the fractal universe in the form of the entropy balance relation $ \delta Q=T_h…

General Physics · Physics 2015-06-12 Ahmad Sheykhi , Zeinab Teimoori , Bin Wang

To investigate the relationship between gravity and thermodynamics in the case of dynamic systems, we interpret the apparent horizon of the Friedmann-Lema\^itre-Robertson-Walker (FLRW) spacetime as a thermodynamic system. We derive the…

General Relativity and Quantum Cosmology · Physics 2023-03-22 Luis M. Sanchez , Hernando Quevedo

We review thermodynamic properties of modified gravity theories such as $F(R)$ gravity and $f(T)$ gravity, where $R$ is the scalar curvature and $T$ is the torsion scalar in teleparallelism. In particular, we explore the equivalence between…

General Relativity and Quantum Cosmology · Physics 2016-06-22 Kazuharu Bamba

A non-equilibrium picture of thermodynamics is discussed at the apparent horizon of FRW universe in $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor. We take two forms of the energy-momentum…

General Relativity and Quantum Cosmology · Physics 2015-06-04 M. Sharif , M. Zubair

By applying the unified first law of thermodynamics on the apparent horizon of FRW universe, we get the entropy relation for the apparent horizon in quasi-topological gravity theory. Throughout the paper, the results of considering the…

General Relativity and Quantum Cosmology · Physics 2016-05-17 H. Moradpour , R. Dehghani

Starting from the first law of thermodynamics, $dE=T_hdS_h+WdV$, at apparent horizon of a FRW universe, and assuming that the associated entropy with apparent horizon has a quantum corrected relation, $S=\frac{A}{4G}-\alpha \ln…

High Energy Physics - Theory · Physics 2011-02-09 Ahmad Sheykhi

In this paper, we study thermodynamical properties of the apparent horizon in a universe governed by quasi-topological gravity. Our aim is twofold. First, by using the variational method we derive the general form of Friedmann equation in…

High Energy Physics - Theory · Physics 2015-06-16 M. H. Dehghani , A. Sheykhi , R. Dehghani

We investigate the thermodynamics at the apparent horizon of the FRW universe in $f(R,T)$ theory under non-equilibrium description. The laws of thermodynamics have been discussed for two particular models of $f(R,T)$ theory. The first law…

General Relativity and Quantum Cosmology · Physics 2014-09-26 M. Sharif , M. Zubair

An equilibrium picture of thermodynamics is discussed at the apparent horizon of FRW universe in $f(T,T_G)$ gravity, where $T$ represents the torsion invariant and $T_G$ is the teleparallel equivalent of the Gauss-Bonnet term. It is found…

General Relativity and Quantum Cosmology · Physics 2015-11-04 M. Zubair

With the usual definitions for the entropy and the temperature associated with the apparent horizon, we show that the unified first law on the apparent horizon is equivalent to the Friedmann equation for the scalar--tensor theory with…

General Relativity and Quantum Cosmology · Physics 2015-07-31 Yumei Huang , Yungui Gong , Dicong Liang , Zhu Yi

We explore the thermodynamic analysis at the apparent horizon in the framework of Rastall theory of gravity. We take different entropies such as the Bakenstein, logarithmic corrected, power law corrected, and the Renyi entropies. We…

General Physics · Physics 2018-12-04 Kazuharu Bamba , Abdul Jawad , Salman Rafique , Hooman Moradpour

This paper explores the non-equilibrium behavior of thermodynamics at the apparent horizon of isotropic and homogeneous universe model in $f(\mathcal{G},T)$ gravity ($\mathcal{G}$ and $T$ represent the Gauss-Bonnet invariant and trace of…

General Relativity and Quantum Cosmology · Physics 2018-03-13 M. Sharif , Ayesha Ikram

By employing the general expression of temperature $T_{h}=|\kappa|/2\pi = \frac{1}{2\pi \tilde{r}_{A}}(1-\frac{\dot{\tilde{r}}_{A}}{2H\tilde{r}_{A}})$ associated with the apparent horizon of a FRW universe and assuming a region of FRW…

General Relativity and Quantum Cosmology · Physics 2009-09-28 M. Akbar
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