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Related papers: Cosmological implications of Rastall-$f(R)$ theory

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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

We present a generalization of Rastall's gravity in which the conservation law of the energy-momentum tensor is altered, and as a result, the trace of the energy-momentum tensor is taken into account together with the Ricci scalar in the…

General Relativity and Quantum Cosmology · Physics 2022-02-24 Clésio E. Mota , Luis C. N. Santos , Franciele M. da Silva , Guilherme Grams , Iarley P. Lobo , Débora P. Menezes

A generalized version for the Rastall theory is proposed showing the agreement with the cosmic accelerating expansion. In this regard, a coupling between geometry and the pressureless matter fields is derived which may play the role of dark…

General Relativity and Quantum Cosmology · Physics 2017-05-24 H. Moradpour , Y. Heydarzade , F. Darabi , Ines G. Salako

The paper deals with generalized Rastall theory of gravity and its cosmological consequences in the background of homogeneous and isotropic flat FLRW model with perfect fluid as the matter context. The model shows a non singular era…

General Relativity and Quantum Cosmology · Physics 2018-10-29 Dipanjana Das , Sourav Dutta , Subenoy Chakraborty

The Rastall's theory is a modification of the General Relativity theory leading to a different expression for the conservation law in the matter sector compared with the usual one. It has been argued recently that such a theory may have…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-29 C. E. M. Batista , J. C. Fabris , M. Hamani Daouda

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

Rastall gravity theory shows notable features consistent with physical observations in comparison to the standard Einstein theory. Recently, there has been a debate about the equivalence of Rastall gravity and general relativity. Motivated…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Wompherdeiki Khyllep , Jibitesh Dutta

The existence of conservation laws is one of the most important requirement of physical theories. Some of them, like energy conservation, knows no experimental exception. However, the generalization of these conservation laws to curved…

General Relativity and Quantum Cosmology · Physics 2012-08-24 J. C. Fabris

Rastall's theory is a modification of General Relativity, based on the non-conservation of the stress-energy tensor. The latter is encoded in a parameter $\gamma$ such that $\gamma = 1$ restores the usual $\nabla_\nu T^{\mu\nu} = 0$ law. We…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 C. E. M. Batista , J. C. Fabris , O. F. Piattella , A. M. Velasquez-Toribio

Using dynamical system analysis, we investigate some cosmological consequences of Rastall gravity coupled to a scalar field (called the Klein-Gordon-Rastall theory) with exponential scalar potential turned on in higher dimensions. From the…

General Relativity and Quantum Cosmology · Physics 2023-10-25 Tegar Ari Widianto , Ahmad Khoirul Falah , Agus Suroso , Husin Alatas , Bobby Eka Gunara

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

In this paper we study the impact of a recent quasar datasample in the constraint of the free parameters of an extension of general relativity. As a ruler to test, we use Rastall gravity in the context of background cosmology being a simple…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-23 Jesús Astorga-Moreno , Kyra Jacobo , Salvador Arteaga , Miguel Ángel García-Aspeitia , Alberto Hernández-Almada

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 paper, after referring to the Rastall theory, we address some of its cosmological consequences. Moreover, bearing the Clausius relation in mind, using Friedman equations in Rastall theory and the Cai-Kim temperature, we obtain a…

General Physics · Physics 2016-12-28 H. Moradpour

Rastall's theory is a generalization of Einstein's equations in which the energy-momentum tensor is not a conserved quantity, its covariant derivative is proportional to the gradient of the Ricci scalar and this fact can be associated with…

General Relativity and Quantum Cosmology · Physics 2015-03-05 A. F. Santos , S. C. Ulhoa

We give a Lagrangian formulation for the theory of Rastall of gravitation. After proposing a Lagrangian density that reproduces the equations of motion postulated by Rastall, we study the cosmological consequences and fit the parameters…

General Relativity and Quantum Cosmology · Physics 2017-01-31 Renato Vieira dos Santos , José A. C. Nogales

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

In this work, we propose a scheme for cosmic evolution in a generalized Rastall gravity. In our approach, the role of dark energy is taken by the non-conserved sector of the stress energy-momentum tensor. The resultant cosmic evolution is…

General Relativity and Quantum Cosmology · Physics 2020-06-08 Kai Lin , Wei-Liang Qian

We have analyzed the implications of a phenomenological model of a built-in cosmological constant of Rastall and Al-Rawaf -Taha type. We have produced the presently observed cosmic acceleration with the aid of introducing a positive…

Astrophysics · Physics 2009-11-07 Arbab I. Arbab

A complete analysis of the dynamics of the Hu-Sawicki modification to General Relativity is presented. In particular, the full phase-space is given for the case in which the model parameters are taken to be n=1, c1=1, and several stable de…

General Relativity and Quantum Cosmology · Physics 2015-11-03 Sulona Kandhai , Peter K. S. Dunsby
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