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Related papers: Modified Friedmann Equations from Tsallis Entropy

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The investigation of modifications to the FLRW cosmology resulting from the consideration of a general entropy for the cosmological apparent horizon is the subject of this study. Building upon the work of Nojiri and collaborators in 2022,…

General Relativity and Quantum Cosmology · Physics 2023-07-26 A. Khodam-Mohammadi , M. Monshizadeh

In the previous analyses in the literature about the generalized second law (GSL) in an accelerated expanding universe the usual area relation for the entropy, i.e. $S={A\over 4G}$, was used for the cosmological horizon entropy. But this…

General Relativity and Quantum Cosmology · Physics 2011-01-14 H. Mohseni Sadjadi , Mubasher Jamil

We investigate the thermodynamics of a spatially flat Friedmann-Robertson-Walker (FRW) universe within the framework of Generalized Proca (GP) theory, a comprehensive vector-tensor theory. By adopting two distinct dark energy models in GP,…

General Relativity and Quantum Cosmology · Physics 2026-01-21 Aofei Sang

In this paper, we obtain the law of emergence with Tsallis entropy from the thermodynamic laws. We first derive the law of emergence from the equilibrium description of the unified first law and Clausius relation. However, it has been shown…

General Relativity and Quantum Cosmology · Physics 2023-01-02 M. Dheepika , Hassan Basari V. T. , Titus K. Mathew

The theoretical and observational consequences of thermodynamics of open systems, which allow particle creation are investigated in modified $f(R,T)$ ($R$ is the Ricci scalar and $T$ is the trace of energy-momentum tensor) theory of gravity…

General Relativity and Quantum Cosmology · Physics 2014-08-26 C. P. Singh , Vijay Singh

Non-extensive Tsallis thermostatistics is a widespread paradigm to describe large-scale gravitational systems. In this work we use Tsallis Cosmology to study thermodynamic gravity and derive modified Friedmann equations. We show that…

General Relativity and Quantum Cosmology · Physics 2025-03-25 Giuseppe Gaetano Luciano , Jaume Gine

An emergence of cosmic space has been suggested by Padmanabhan in [arXiv:1206.4916]. This new interesting approach argues that the expansion of the universe is due to the difference between the number of degrees of freedom on a holographic…

High Energy Physics - Theory · Physics 2014-04-17 Ahmed Farag Ali

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 study the modified Friedmann equation in the Friedmann-Robertson-Walker universe with quantum effect. Our modified results mainly stem from the new entropy-area relation and the novel idea of T. Padmanabhan, who considers the cosmic…

General Relativity and Quantum Cosmology · Physics 2018-03-15 Wei Zhang , Xiao-Mei Kuang

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

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 investigate the first law of thermodynamics and entropy associated to the apparent horizon of (non-flat) FLRW space-time in different theories of modified gravity and in the presence of a perfect fluid of matter. We pose our attention on…

General Relativity and Quantum Cosmology · Physics 2023-11-21 Lorenzo Sebastiani

The recent research on the connection between gravity and thermodynamics suggests that gravity could be an emergent phenomenon. Following this, Padmanabhan proposed a novel idea that the expansion of the universe can be interpreted as…

General Relativity and Quantum Cosmology · Physics 2022-06-22 P. B. Krishna , Hassan Basari V. T. , Titus K Mathew

We explore a cosmological model inspired by the modified Kaniadakis entropy and disclose the influences of the modified Friedmann equations on the evolution of the Universe. We find that in modified Kaniadakis cosmology with only…

General Relativity and Quantum Cosmology · Physics 2024-10-01 Mahdi Kord Zangeneh , Ahmad Sheykhi

In this paper we have examined the validity of the generalized second law of thermodynamics (GSLT) in an expanding Friedmann Robertson Walker (FRW) universe filled with different variants of Chaplygin gases. Assuming that the universe is a…

General Physics · Physics 2021-02-19 Samarjit Chakraborty , Sarbari Guha

Padmanabhan [arXiv:1206.4916] argues that the cosmic acceleration can be understood from the perspective that spacetime dynamics is an emergence phenomena. By calculating the difference between the surface degrees of freedom and the bulk…

General Relativity and Quantum Cosmology · Physics 2013-04-19 Ahmad Sheykhi

We investigate the gravitational origin of the Tsallis entropy, characterized by the nonadditive index $\delta$. Utilizing Wald's formalism within the framework of $f(R)$ modified theories of gravity, we evaluate the entropy on the black…

General Relativity and Quantum Cosmology · Physics 2024-09-02 Rocco D'Agostino , Giuseppe Gaetano Luciano

Here, cosmology of the late and future universe is obtained from $f(R)$-gravity with non-linear curvature terms $R^2$ and $R^3$ ($R$ being the Ricci scalar curvature). It is different from $f(R)$-dark enrgy models, where non-linear…

General Relativity and Quantum Cosmology · Physics 2009-09-17 S. K. Srivastava

We develop new modified cosmological scenarios by applying the first law of thermodynamics at the Universe horizon, utilizing a new entropic functional that generalizes the standard Boltzmann-Gibbs-Shannon entropy. In particular, starting…

General Relativity and Quantum Cosmology · Physics 2026-02-24 G. G. Luciano , E. N. Saridakis

According to the quantum deformation approach to quantum gravity, the thermodynamical entropy of a quantum-deformed (q-deformed) black hole with horizon area $A$ established by Jalalzadeh is expressed as $S_q = \pi\sin \left(…

General Relativity and Quantum Cosmology · Physics 2024-05-20 Jianming Chen , Gerui Chen
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