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Related papers: Thermodynamics in Modified Gravity Theories

200 papers

First and second laws of black hole thermodynamics are examined at the apparent horizon of FRW spacetime in $f(R,R_{\alpha\beta}R^{\alpha\beta} ,\phi)$ gravity, where $R$, $R_{\alpha\beta}R^{\alpha\beta}$ and $\phi$ are the Ricci scalar,…

General Relativity and Quantum Cosmology · Physics 2016-11-17 M. Zubair , Farzana Kousar , Sebastian Bahamonde

There is a deep link between gravity and thermodynamics; in a precise way gravity can be derived from entanglement entropy in conformal field theories. However, this depends crucially on properties of horizons, and asymptotic symmetries of…

High Energy Physics - Theory · Physics 2025-04-30 Ian Nagle

In arXiv:gr-qc/9504004 it was shown that the Einstein equation can be derived as a local constitutive equation for an equilibrium spacetime thermodynamics. More recently, in the attempt to extend the same approach to the case of $f(R)$…

General Relativity and Quantum Cosmology · Physics 2010-04-06 G. Chirco , S. Liberati

With the usual definitions for the entropy and the temperature associated with the apparent horizon, we discuss the first law of the thermodynamics on the apparent in the general scalar-tensor theory of gravity with the kinetic term of the…

General Relativity and Quantum Cosmology · Physics 2016-03-04 Yumei Huang , Yungui Gong

This research is aimed at the revision of the thermodynamic concepts and their relationship with the General Relativity Theory (GRT) and how physical systems are affected when gravity is included in their thermodynamic description. We found…

General Relativity and Quantum Cosmology · Physics 2013-07-25 W. A. Rojas C. , R. Arenas S

In this work, we explore the formalism of the irreversible thermodynamics of open systems and the possibility of gravitationally generated particle production in modified gravity. More specifically, we consider the scalar-tensor…

General Relativity and Quantum Cosmology · Physics 2023-06-27 Miguel A. S. Pinto , Tiberiu Harko , Francisco S. N. Lobo

We analyze the thermodynamic properties of the apparent horizon of Friedmann-Lema\^itre-Roberson-Walker (FLRW) spacetimes in Einstein-Gauss-Bonnet gravity. We use the generalized definition of entropy for gravity theories in higher…

General Relativity and Quantum Cosmology · Physics 2025-10-10 Luis M. Sánchez , Hernando Quevedo

We study the generalized second law (GSL) of thermodynamics in $f(T)$ cosmology. We consider the universe as a closed bounded system filled with $n$ component fluids in the thermal equilibrium with the cosmological boundary. We use two…

General Physics · Physics 2013-02-25 Kazuharu Bamba , Mubasher Jamil , D. Momeni , Ratbay Myrzakulov

We generalize previous work by considering a novel gravitational model with an action given by an arbitrary function of the Ricci scalar, the matter Lagrangian density, a scalar field and a kinetic term constructed from the gradients of the…

General Relativity and Quantum Cosmology · Physics 2013-02-06 Tiberiu Harko , Francisco S. N. Lobo , Olivier Minazzoli

In gravity theories derived from a f(R) Lagrangian, matter is usually supposed to be minimally coupled to the metric, which hence defines a ``Jordan frame.'' However, since the field equations are fourth order, gravity possesses an extra…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Nathalie Deruelle , Misao Sasaki , Yuuiti Sendouda

The non-equivalence between the metric and Palatini formalisms of $f(R)$ gravity is an intriguing feature of these theories. However, in the recently proposed hybrid metric-Palatini gravity, consisting of the superposition of the metric…

General Relativity and Quantum Cosmology · Physics 2013-08-23 Salvatore Capozziello , Tiberiu Harko , Francisco S. N. Lobo , Gonzalo J. Olmo

It was shown recently that, in the case of Schwarschild black hole, one can obtain the correct thermodynamic relations by studying a model quantum system and using a particular duality transformation. We study this approach further for the…

General Relativity and Quantum Cosmology · Physics 2009-03-19 Sudipta Sarkar , T. Padmanabhan

It is very likely that the quantum description of spacetime is quite different from what we perceive at large scales, $l\gg (G\hbar/c^3)^{1/2}$. The long wave length description of spacetime, based on Einstein's equations, is similar to the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 T. Padmanabhan

We present a framework for discussing the cosmology of dark energy and dark matter based on two scalar degrees of freedom. An effective field theory of cosmological perturbations is employed. A unitary gauge choice renders the dark energy…

High Energy Physics - Theory · Physics 2014-04-01 László Á. Gergely , Shinji Tsujikawa

We give a short review of the recent developments of entropic cosmology based on two thermodynamic laws of the apparent horizon, namely the first and the second laws of thermodynamics. The first law essentially provides the change of the…

General Relativity and Quantum Cosmology · Physics 2024-09-04 Shin'ichi Nojiri , Sergei D. Odintsov , Tanmoy Paul

Considering the Einstein field equations in Lyra manifold, and applying the unified first law of thermodynamics as well as the Clausius relation to the apparent horizon of FRW universe, we find the entropy of apparent horizon in Lyra…

General Relativity and Quantum Cosmology · Physics 2017-09-12 H. Moradpour , N. Sadeghnezhad , S. Ghaffari , A. Jahan

We consider the energetics and thermodynamics of spacetimes with no horizons, but endowed with a preferred timelike junction surface. They could arise as a limiting case of the gravastar and other constructions regularizing the interior of…

General Relativity and Quantum Cosmology · Physics 2025-07-08 Raymond Isichei , João Magueijo

We investigate the emergence of cosmic hysteresis in cyclic bouncing cosmologies within the framework of $f(R)$ modified gravity theories. Building upon previous studies that explored hysteresis phenomena in braneworld and…

General Relativity and Quantum Cosmology · Physics 2025-06-12 Aritra Sanyal

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

Entropic cosmology with the R\'{e}nyi entropy of the apparent horizon $S_R=(1/\alpha)\ln(1+\alpha S_{BH})$, where $S_{BH}$ is the Bekenstein--Hawking entropy, is studied. By virtue of the thermodynamics-gravity correspondence a model of…

General Physics · Physics 2026-05-04 S. I. Kruglov
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