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Related papers: A thermodynamics revision of Rastall gravity

200 papers

We calculate static and spherically symmetric solutions for the Rastall modification of gravity to describe Neutron Stars (NS). The key feature of the Rastall gravity is the non-conservation of the energy-momentum tensor proportionally to…

General Relativity and Quantum Cosmology · Physics 2016-10-24 A. M. Oliveira , H. E. S. Velten , J. C. Fabris , L. Casarini

The aim of this paper is to perform stability analysis of anisotropic dissipative cylindrical collapsing model in $f(R,T,R_{\mu\nu} T^{\mu\nu})$ gravity. In this context, the modified version of hydrodynamical equation is explored by means…

General Relativity and Quantum Cosmology · Physics 2017-09-14 Z. Yousaf , M. Zaeem-ul-Haq Bhatti , Ume Farwa

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

According to maximum entropy principle, it has been proved that the gravitational field equations could be derived by the extrema of total entropy for perfect fluid, which implies that thermodynamic relations contain information of gravity.…

General Relativity and Quantum Cosmology · Physics 2018-01-17 Xiongjun Fang , Xiaokai He , Jiliang Jing

We study spherically symmetric gravitational collapse of a homogeneous perfect fluid in Rastall gravity. Considering a linear equation of state (EoS) for the fluid profiles, we examine the conditions under which the collapse scenario could…

General Relativity and Quantum Cosmology · Physics 2019-05-08 A. H. Ziaie , H. Moradpour , S. Ghaffari

Rastall gravity is a generalization of the Einstein gravity in which the matter is not conserved in the presence of a non-constant spacetime curvature. In this report, we analyze Rastall gravity using the linearized formalism. The…

General Relativity and Quantum Cosmology · Physics 2025-05-12 Yuwadee Tongkong

Rastall's theory is a modification of Einstein's theory of gravity where the covariant divergence of the stress-energy tensor is no more vanishing, but proportional to the gradient of the Ricci scalar. The motivation of this theory is to…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Gabriel F. Silva , Oliver F. Piattella , Julio C. Fabris , Luciano Casarini , Taislane O. Barbosa

A relativistic self-gravitating equilibrium system with steady flow as well as spherical symmetry is discovered. The energy-momentum tensor contains the contribution of a current related to the flow and the metric tensor does an…

General Relativity and Quantum Cosmology · Physics 2026-01-08 Shuichi Yokoyama

The thermal history of a large class of running vacuum models in which the effective cosmological term is described by a truncated power series of the Hubble rate, whose dominant term is $\Lambda (H) \propto H^{n+2}$, is discussed in…

General Relativity and Quantum Cosmology · Physics 2016-04-29 J. A. S. Lima , Spyros Basilakos , Joan Solà

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

We study thermodynamics in $f(R)$ gravity with the disformal transformation. The transformation applied to the matter Lagrangian has the form of $\g_{\m\n} = A(\phi,X)g_{\m\n} + B(\phi,X)\pa_\m\f\pa_\n\f$ with the assumption of the…

General Relativity and Quantum Cosmology · Physics 2019-02-14 Chao-Qiang Geng , Wei-Cheng Hsu , Jhih-Rong Lu , Ling-Wei Luo

Recently, a morphological transition in the velocity distribution of a relativistic gas has been pointed out which shows hallmarks of a critical phenomenon. Here, we provide a general framework which allows for a thermodynamic approach to…

Statistical Mechanics · Physics 2015-10-21 Afshin Montakhab , Leila Shahsavar , Malihe Ghodrat

In this work we further extend the analysis of $f(R)$ theories of gravity in the metric formalism under the approach of a Thermodynamics analogy, proposed in arXiv:1911.04830v3. Here we assume a double-well inflationary potential in the…

General Relativity and Quantum Cosmology · Physics 2023-06-21 C. D. Peralta , S. E. Jorás

The effects of the cosmological constant on the static equilibrium configurations and stability against small radial perturbations of relativistic polytropic spheres are investigated. This study numerically solves the hydrostatic…

General Relativity and Quantum Cosmology · Physics 2020-04-15 José D. V. Arbañil , Pedro H. R. S. Moraes

In this work, two models of metric $f(R)$ gravity in the Jordan frame are investigated as a dynamical description of the late-time cosmic expansion using binned Type Ia Supernovae data. The aim is to provide an explanation for the effective…

General Relativity and Quantum Cosmology · Physics 2026-04-15 A. Valletta , G. Montani , M. G. Dainotti , E. Fazzari

Rastall gravity is the same as General Relativity, with a simple algebraic redefinition of what is called the energy-momentum tensor. Despite it having been very clearly explained by M. Visser several years go, there are still many papers…

General Relativity and Quantum Cosmology · Physics 2024-07-11 Alexey Golovnev

The cosmological implications of New Tsallis holographic dark energy (NTHDE) in Rastall theory have been studied. Using the data set that includes DESI BAO (DR2), PantheonPlus SNe Ia, H(z) measurements, and BBN and the MCMC analysis, the…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-11 N. Sadeghnezhad , R. Jalalzadeh , Z. Davari , B. Afshar

Rastall's theory is based on the non-conservation of the energy-momentum tensor. We show that, in this theory, if we introduce a two-fluid model, one component representing vacuum energy whereas the other pressureless matter (e.g. baryons…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-27 Carlos E. M. Batista , Mahamadou H. Daouda , Júlio C. Fabris , Oliver F. Piattella , Davi C. Rodrigues

In this paper, we have analyzed the geometrical and dynamical parameters of $\mathcal{F}(R, \mathcal{G})=\alpha R^2 \mathcal{G}^\beta$ cosmological model, ($R$, $\mathcal{G}$ being the Ricci scalar and Gauss-Bonnet invariant respectively),…

General Relativity and Quantum Cosmology · Physics 2023-10-11 Santosh V. Lohakare , Krishna Rathore , B. Mishra

In the metric approach of $f(R)$ theories of gravity, the fourth-order field equations are often recast as effective Einstein equations in the presence of standard matter and a curvature fluid (which gathers all the extra terms), always in…

General Relativity and Quantum Cosmology · Physics 2020-12-01 Juan M. Z. Pretel , Sergio E. Jorás , Ribamar R. R. Reis