English
Related papers

Related papers: On Rastall gravity formulation as a $f(R,\mathcal{…

200 papers

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

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

Rastall generalized Einstein's field equations relaxing the Einstein's assumption that the covariant divergence of the energy-momentum tensor should vanish. His field equations contain a free parameter alpha and in an empty space, i.e. if…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Vladimir Majernik , Lukas Richterek

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 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

We consider f(R,T) modified theories of gravity, where the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar R and of the trace of the stress-energy tensor T. We obtain the gravitational field equations in the…

General Relativity and Quantum Cosmology · Physics 2011-07-14 Tiberiu Harko , Francisco S. N. Lobo , Shin'ichi Nojiri , Sergei D. Odintsov

Recently, a generalized gravity theory was proposed by Harko etal where the Lagrangian density is an arbitrary function of the Ricci scalar R and the trace of the stress-energy tensor T, known as F(R,T) gravity. In their derivation of the…

General Physics · Physics 2015-06-12 Subenoy Chakraborty

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

Here we propose the extended modified gravity theory named as $f(R,G,\mathcal{T})$ gravity where $R$ is the Ricci scalar, $G$ is the Gauss-Bonnet invariant and $\mathcal{T}$ is the trace of the stress-energy tensor. We derive the…

General Relativity and Quantum Cosmology · Physics 2020-12-02 Ujjal Debnath

We generalize previous work by considering a novel gravitational model with an action given by an arbitrary function of the Ricci scalar, the matter Lagrangian density, a scalar field and a kinetic term constructed from the gradients of the…

General Relativity and Quantum Cosmology · Physics 2013-02-06 Tiberiu Harko , Francisco S. N. Lobo , Olivier Minazzoli

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

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 generalize the $f(R)$ type gravity models by assuming that the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar $R$ and of the matter Lagrangian $L_m$. We obtain the gravitational field equations in the…

General Relativity and Quantum Cosmology · Physics 2011-02-09 Tiberiu Harko , Francisco S. N. Lobo

The actions of the ``$R=T$'' and string-inspired theories of gravity in (1+1) dimensions are generalized into one single action which is characterized by two functions. We discuss differing interpretations of the matter stress-energy…

General Relativity and Quantum Cosmology · Physics 2010-04-06 J. S. F. Chan , R. B. Mann

The $f(R,T)$ gravity is a theory whose gravitational action depends arbitrarily on the Ricci scalar, $R$, and the trace of the stress-energy tensor, $T$; its field equations also depend on matter Lagrangian, $\mathcal{L}_{m}$. In the…

General Relativity and Quantum Cosmology · Physics 2021-02-11 G. A. Carvalho , F. Rocha , H. O. Oliveira , R. V. Lobato

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

The $1/r$-expansion in the distance to the source is applied to the linearized $f(R)$ gravity, and its multipole expansion in the radiation field with irreducible Cartesian tensors is presented. Then, the energy, momentum, and angular…

General Relativity and Quantum Cosmology · Physics 2018-04-25 Bofeng Wu , Chao-Guang Huang

We consider cosmological scenarios based on $f(R,T)$ theories of gravity ($R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor) and numerically reconstruct the function $f(R,T)$ which is able to reproduce the same…

General Relativity and Quantum Cosmology · Physics 2015-03-19 M. J. S. Houndjo , Oliver F. Piattella

Recently a Lagrangian formulation for Rastall Gravity (RG) has been proposed in the framework of f(R, T) gravity. In the present work we obtain Lagrangian formulation for the standard Rastall theory assuming the matter content is a perfect…

General Relativity and Quantum Cosmology · Physics 2020-03-05 Hamid Shabani , Amir Hadi Ziaie

I propose an alternative $f(R)$ theory of gravity constructed by applying the function $f$ directly to the Ricci tensor instead of the Ricci scalar. The main goal of this study is to derive the resulting modified Einstein equations for the…

General Relativity and Quantum Cosmology · Physics 2017-08-16 Tomasz Stachowiak
‹ Prev 1 2 3 10 Next ›