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Related papers: A thermodynamics revision of Rastall gravity

200 papers

We investigate stability of the Einstein static solution against homogeneous scalar, vector and tensor perturbations in the context of Rastall theory of gravity. We show that this solution in the presence of perfect fluid and vacuum energy…

General Relativity and Quantum Cosmology · Physics 2018-07-10 F. Darabi , K. Atazadeh , Y. Heydarzade

In this work, we have developed an FLRW type model of a universe which displays transition from deceleration in the past to the acceleration at the present. For this, we have considered field equations of $f(R,T)$ gravity and have taken…

General Relativity and Quantum Cosmology · Physics 2023-03-27 Anirudh Pradhan , Gopikant Goswami , Aroonkumar Beesham

In the saddle point approximation, the Euclidean path integral for quantum gravity closely resembles a thermodynamic partition function, with the cosmological constant $\Lambda$ playing the role of temperature and the ``density of…

General Relativity and Quantum Cosmology · Physics 2010-04-28 Steven Carlip

Einstein's famous equivalence principle is certainly one of the most striking features of the gravitational interaction. In a strict reading, it states that the effects of gravity can be made to disappear $locally$ by a convenient choice of…

General Relativity and Quantum Cosmology · Physics 2023-08-02 Daniel A. T. Vanzella

In Cuzinatto et al. [Phys. Rev. D 93, 124034 (2016)], it has been demonstrated that theories of gravity in which the Lagrangian includes terms depending on the scalar curvature $R$ and its derivatives up to order $n$, i.e.…

General Relativity and Quantum Cosmology · Physics 2019-05-07 R. R. Cuzinatto , C. A. M. de Melo , L. G. Medeiros , P. J. Pompeia

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

The influence of spatial dimensionality and particle-antiparticle pair production on the thermodynamic properties of the relativistic Fermi gas, at finite chemical potential, is studied. Resembling a kind of phase transition, qualitatively…

Statistical Mechanics · Physics 2014-07-29 Francisco J. Sevilla , Omar Piña

The covariant canonical transformation theory applied to the relativistic Hamiltonian theory of classical matter fields in dynamical space-time yields a novel (first order) gauge field theory of gravitation. The emerging field equations…

General Relativity and Quantum Cosmology · Physics 2023-11-29 David Vasak , Johannes Kirsch , Dirk Kehm , Juergen Struckmeier

Relativistic effects in the thermodynamical properties of interacting particle systems are investigated within the framework of the relativistic direct interaction theory in various forms of dynamics. In the front form of relativistic…

High Energy Physics - Theory · Physics 2007-05-23 V. Tretyak

The stability of the equilibrium state is one of the crucial tests a hydrodynamic theory needs to pass. A widespread technique to study this property consists of searching for a Lyapunov function of the linearised theory, in the form of a…

General Relativity and Quantum Cosmology · Physics 2021-09-30 Lorenzo Gavassino

We perform analytic linear stability analyses of an interface separating two stratified media threaded by a radiation flux, a configuration relevant in several astrophysical contexts. We develop a general framework for analyzing such…

Solar and Stellar Astrophysics · Physics 2015-05-27 Emmanuel Jacquet , Mark Krumholz

The purpose of this paper is to study the transport equation and its coupling with Maxwell equation in the framework of R^n gravity. Using Muller-Israel-Stewart theory for the conduction of dissipative fluids, we analyze the temperature,…

General Relativity and Quantum Cosmology · Physics 2017-05-22 Hafiza Rizwana Kausar

Cosmological implications of a generalized Rastall theory where the non-conservation equation is promoted to accepts arbitrary functions of the Ricci scalar is considered. We have obtain the model parameters of the power-law ansatz…

General Relativity and Quantum Cosmology · Physics 2021-10-13 Shahab Shahidi

The Dark Sector is described by an additional barotropic fluid which evolves adiabatically during the universe's history and whose adiabatic exponent $\gamma$ is derived from the standard definitions of specific heats. Although in general…

General Relativity and Quantum Cosmology · Physics 2016-11-02 Peter K. S. Dunsby , Orlando Luongo , Lorenzo Reverberi

Dynamical analysis of spherically symmetric collapsing star surrounding in locally anisotropic environment with expansion-free condition is presented in $f(R,T)$ gravity, where $R$ corresponds to Ricci scalar and $T$ stands for the trace of…

General Relativity and Quantum Cosmology · Physics 2015-04-21 Ifra Noureen , M. Zubair

In the Regge-Teitelboim model, gravity is described by embedding the space-time manifold in a (usually flat) fixed higher-dimensional background, where the embedding coordinates, rather than the metric tensor, are the dynamical degrees of…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-30 S. R. Pinto , C. J. A. P. Martins

A cosmological model with a specific form of the Hubble parameter is constructed in a flat homogeneous, and isotropic background in the framework of $f(R, T)$ gravity, where $R$ is the scalar curvature and $T$ is the trace of the…

General Relativity and Quantum Cosmology · Physics 2018-07-04 J. K. Singh , Kazuharu Bamba , Ritika Nagpal , S. K. J. Pacif

This work comprises a study of the thermodynamic behavior of modified $f(\bar{R},\bar{T})$ gravity, which had been developed based on a non-canonical theory known as K-essence theory. In this development, we use the Dirac-Born-Infeld (DBI)…

General Relativity and Quantum Cosmology · Physics 2024-10-14 Arijit Panda , Goutam Manna , Saibal Ray , Maxim Khlopov , Praveen Kumar Dhankar

We propose a new model of cosmology based on an anisotropic background and a specific $f(R)$ theory of gravity. It is shown that field equations of $f(R)$ gravity in a Bianchi type I background give rise to a modified Friedmann equation.…

General Relativity and Quantum Cosmology · Physics 2024-03-21 Cemsinan Deliduman , Oguzhan Kasikci , Vildan Keles Tugyanoglu

We review the difficulties of the generalized Chaplygin gas model to fit observational data, due to the tension between background and perturbative tests. We argue that such issues may be circumvented by means of a self-interacting scalar…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 J. C. Fabris , O. F. Piattella , D. C. Rodrigues , C. E. M. Batista , M. H. Daouda