English
Related papers

Related papers: Modified Entropy from Action Principle

200 papers

Considering the modified entropy-area relation from DSR-GUP (Doubly special relativity-Generalized uncertainity principle), we obtain the modified Friedmann equations from the first law of thermodynamics at apparent horizon. Due to the…

General Relativity and Quantum Cosmology · Physics 2020-04-01 Özgür Ökcü , Christian Corda , Ekrem Aydiner

We apply the generalized second law of thermodynamics to discriminate among quantum corrections (whether logarithmic or power-law) to the entropy of the apparent horizon in spatially Friedmann-Robertson-Walker universes. We use the…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Ninfa Radicella , Diego Pavón

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

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

In this paper we first obtain Friedmann equations for the $(n-1)$-dimensional brane embedded in the $(n+1)$-dimensional bulk, with intrinsic curvature term of the brane included in the action (DGP model). Then, we show that one can always…

High Energy Physics - Theory · Physics 2008-11-26 Ahmad Sheykhi , Bin Wang , Rong-Gen Cai

Since the seminal work of Verlinde, the idea that gravity may be an emergent force of entropic origin has gained widespread attention. Many generalizations of this key idea have been considered in the literature, starting from well-known…

General Relativity and Quantum Cosmology · Physics 2023-06-19 Kamel Ourabah

We study the irreversible (non-equilibrium) thermodynamics of FRW universe containing only dark energy. Using the modified entropy-area relation which is motivated from the loop quantum gravity, we calculate the entropy-corrected form of…

General Relativity and Quantum Cosmology · Physics 2010-09-14 K. Karami , Mubasher Jamil , N. Sahraei

In this paper we revisit the relation between the Friedmann equations and the first law of thermodynamics. We find that the unified first law firstly proposed by Hayward to treat the "outer"trapping horizon of dynamical black hole can be…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Rong-Gen Cai , Li-Ming Cao

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

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

Here, we consider new nonadditive entropy of the apparent horizon $S_K=S_{BH}/(1+\gamma S_{BH})$ with $S_{BH}$ being the Bekenstein--Hawking entropy. This is an alternative of the R\'{e}nyi and Tsallis entropies, that allows us, by…

General Physics · Physics 2025-11-18 S. I. Kruglov

Using the generalized procedure proposed by \emph{Wu et al}\cite{wu} recently, we construct the first law of thermodynamics on apparent horizon in a general braneworld model with curvature correction terms on the brane and in the bulk,…

General Relativity and Quantum Cosmology · Physics 2010-01-07 Tao Zhu , Ji-Rong Ren , Shu-Fan Mo

A remarkable new idea on the origin of gravity was recently proposed by Verlinde who claimed that the laws of gravitation are no longer fundamental, but rather emerge naturally as an entropic force. In Verlinde derivation, the equipartition…

General Physics · Physics 2018-10-09 A. Sheykhi , Z. Teimoori

The Friedmann equation in the Friedmann-Robertson-Walker(FRW) universe with any spatial curvature is derived from the first law of thermodynamics on the event horizon. The key idea is to redefine a Hawking temperature on the event horizon.…

High Energy Physics - Theory · Physics 2016-03-08 Fei-Quan Tu , Yi-Xin Chen

Here in this work we propose a modified gravity with the action of $f(R) = \sqrt{R^2 - R_0^2}$ instead of Einstein-Hilbert action to describe the late time acceleration of the universe. We obtain the equation of the modified gravity both in…

Astrophysics · Physics 2008-11-26 Shant Baghram , Marzieh Farhang , Sohrab Rahvar

Gravity is derived from an entropic action coupling matter fields with geometry. The fundamental idea is to relate the metric of Lorentzian spacetime to a quantum operator, playing the role of an renormalizable effective density matrix and…

General Relativity and Quantum Cosmology · Physics 2025-03-20 Ginestra Bianconi

Modifications to gravity that add additional functions of the Ricci curvature to the Einstein-Hilbert action -- collectively known as $f(R)$ theories -- have been studied in great detail. When considered as complete theories of gravity they…

Astrophysics · Physics 2009-02-20 Simon DeDeo , Dimitrios Psaltis

We explore the thermodynamic and entanglement properties of dynamical black holes based on the recently proposed dynamical black hole entropy by Hollands-Wald-Zhang. We first provide direct proof that, under first-order perturbations, the…

High Energy Physics - Theory · Physics 2026-05-20 Weizhen Jia , Qiongyu Qi , Christina Gao

The thermodynamics-gravity conjecture reveals that one can derive the gravitational field equations by using the first law of thermodynamics and vice versa. Considering the entropy associated with the horizon in the form of non-extensive…

General Relativity and Quantum Cosmology · Physics 2021-11-04 Mahnaz Asghari , Ahmad Sheykhi

The present study is elaborated to investigate the validity of thermodynamical laws in a modified teleparallel gravity based on higher-order derivatives terms of torsion scalar. For this purpose, we consider spatially flat FRW model filled…

General Physics · Physics 2019-06-07 Saira Waheed , M. Zubair