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Related papers: A thermodynamics revision of Rastall gravity

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In this paper, we investigate the stability of the flat FLRW metric in $f(T)$ gravity. This is achieved by analysing the small perturbations, $\delta$ about the Hubble parameter and the matter energy density, $\delta_\text{m}$. We find that…

General Relativity and Quantum Cosmology · Physics 2017-01-03 Gabriel Farrugia , Jackson Levi Said

A cyclic flat universe with quintom behaviour and future big rip has been presented in the framework of Rastall gravity, which is an extension of the standard $\Lambda$CDM model. The Hubble parameter oscillates periodically between positive…

General Relativity and Quantum Cosmology · Physics 2025-03-18 Nasr Ahmed , Anirudh Pradhan , Archana Dixit

In an attempt to look for a viable mechanism leading to a present-day accelerated expansion, we investigate the possibility that the observed cosmic speed up may be recovered in the framework of the Rastall's theory, relying on the…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-12 Monica Capone , Vincenzo Fabrizio Cardone , Matteo Luca Ruggiero

In this note, we investigate the stability of the dark energy model from time crystals proposed in [1]. We emphasize two ingredients, the coupling of the scalar field to gravity, and the fact that these time crystals are on an expanding FRW…

General Relativity and Quantum Cosmology · Physics 2025-08-27 Laura Mersini-Houghton

This study conducts a meticulous examination of the cosmological implications inherent in Rastall gravity and $f(R)$ gravity models, assessing their efficacy across distinct cosmic epochs, from early universe structure formation to…

General Relativity and Quantum Cosmology · Physics 2025-01-14 Muhammad Yarahmadi , Amin Salehi , Hadis Mousavi

Within the context of Rastall gravity, we investigate the hydrostatic equilibrium and dynamical stability against radial pulsations of compact stars, where a free parameter $\beta$ measures the deviations from General Relativity (GR). We…

General Relativity and Quantum Cosmology · Physics 2024-07-01 Juan M. Z. Pretel , Clésio E. Mota

In this paper, we investigate the thermodynamic aspects of quadratic gravity in a $D$-dimensional Friedmann-Lemaitre-Robertson-Walker (FLRW) universe. First, we derive the field equations and the effective energy-momentum tensor for…

General Relativity and Quantum Cosmology · Physics 2025-07-17 Navid Safarzadeh Ilkhchi , Amin Rezaei Akbarieh , Yaghoub Heydarzade

Rastall gravity is a modified gravity proposal that incorporates a non-conserved energy momentum tensor (EMT). We study the equivalence between Rastall gravity and general relativity, analyzing its consequences for an EMT of dark matter and…

General Relativity and Quantum Cosmology · Physics 2023-03-08 Javier Chagoya , López-Domínguez , C. Ortiz

Recently a modified version of Rastall theory of gravity has been introduced in which a varying coupling parameter could act as dark energy (DE) and thus, it can be held responsible for the current accelerated expansion of the Universe.…

General Physics · Physics 2020-11-20 A. H. Ziaie , H. Moradpour , H. Shabani

This study explores the application of complexity factor within the context of Rastall gravity, exploring its implications on a static spacetime admitting spherical symmetry associated with anisotropic fluids under an electromagnetic field.…

General Relativity and Quantum Cosmology · Physics 2025-08-20 Tayyab Naseer

The Rastall gravity is a modification of Einstein's general relativity, in which the energy-momentum conservation is not satisfied and depends on the gradient of the Ricci curvature. It is in dispute whether the Rastall gravity is…

Astrophysics of Galaxies · Physics 2020-08-26 Meirong Tang , Zhaoyi Xu , Jiancheng Wang

Molecular dynamics simulations of a three dimensional relativistic gas with a soft potential are conducted with different interactions and particle masses. For all cases the velocity distribution agrees numerically with the J\"uttner…

Statistical Mechanics · Physics 2020-10-07 Noah Kubli , Hans J. Herrmann

Bearing holographic dark energy hypothesis in mind, the ability of vacuum energy in describing the current accelerated universe is studied in the framework of Rastall theory. Here, in addition to the ordinary approach in which it is…

General Relativity and Quantum Cosmology · Physics 2020-11-17 S. Ghaffari , A. A. Mamon , H. Moradpour , A. H. Ziaie

The present work looks for the possible existence of static and spherically symmetric wormhole geometries in Rastall-Rainbow gravity. Since, the Rastall-Rainbow gravity model has been constructed with the combination of Rastall theory and…

General Relativity and Quantum Cosmology · Physics 2024-06-07 Abdelghani Errehymy , Ayan Banerjee , Orhan Donmez , Mohammed Daoud , Kottakkaran Sooppy Nisar , Abdel-Haleem Abdel-Aty

In this paper, we study the model of $f(T, B)$ gravity with viscous fluid in flat-FRW metric, in which $T$ and $B$ are torsion scalar and boundary term, respectively. We obtain the Friedmann equations in the framework of modified…

General Relativity and Quantum Cosmology · Physics 2019-09-02 A. Pourbagher , Alireza Amani

This paper starts from a toy model for inflation in a class of modified theories of gravity in the metric formalism. Instead of the standard procedure -- assuming a non-linear Lagrangian $f(R)$ in the Jordan frame -- we start from a simple…

General Relativity and Quantum Cosmology · Physics 2020-07-01 C. D. Peralta , S. E. Jorás

We intend to study a new class of cosmological models in $f(R, T)$ modified theories of gravity, hence define the cosmological constant $\Lambda$ as a function of the trace of the stress energy-momentum-tensor $T$ and the Ricci scalar $R$,…

General Physics · Physics 2020-03-26 Safiqul Islam , Praveen Kumar , G. S. Khadekar , Tapas K Das

Amongst a number of modified theories of gravity, the Rastall theory has been propounded to address some shortcomings of the standard theory of general relativity. Our purpose is to investigate this framework's capacity to analyse stellar…

General Relativity and Quantum Cosmology · Physics 2018-07-04 Sudan Hansraj , Ayan Banerjee

Rastall gravity, originally developed in 1972, is currently undergoing a significant surge in popularity. Rastall gravity purports to be a modified theory of gravity, with a non-conserved stress-energy tensor, and an unusual non-minimal…

General Relativity and Quantum Cosmology · Physics 2018-05-30 Matt Visser

The Rastall's theory is a modification of General Relativity touching one of the cornestone of gravity theory: the conservation laws. In Rastall's theory, the energy-momentum tensor is not conserved anymore, depending now on the gradient of…

General Relativity and Quantum Cosmology · Physics 2015-06-19 J. C. Fabris , O. F. Piattella , D. C. Rodrigues , M. H. Daouda