English
Related papers

Related papers: $\kappa(R,T)$ gravity

200 papers

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

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

This article presents cosmological models that arise in a subclass of $f(R,T)=f(R)+f(T)$ gravity models, with different $f(R)$ functions and fixed $T$-dependence. That is, the gravitational lagrangian is considered as $f(R,T)=f(R)+\lambda…

General Relativity and Quantum Cosmology · Physics 2018-09-18 P. K. Sahoo , P. H. R. S. Moraes , Parbati Sahoo , Binaya K. Bishi

We generalize and unify the $f(R,T)$ and $f(R,L_m)$ type gravity models by assuming that the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar $R$, of the trace of the energy-momentum tensor $T$, and of the…

General Relativity and Quantum Cosmology · Physics 2021-07-28 Zahra Haghani , Tiberiu Harko

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

We study $f(R,T)$ gravity, in which the curvature $R$ appearing in the gravitational Lagrangian is replaced by an arbitrary function of the curvature and the trace $T$ of the stress-energy tensor. We focus primarily on situations where $f$…

General Relativity and Quantum Cosmology · Physics 2019-10-02 Sarah B. Fisher , Eric D. Carlson

The non-conservation of the energy-momentum tensor in $f(R,T)$ gravity can be interpreted as an effective manifestation of dissipation. Motivated by this, we propose a new formulation of $f(R,T)$ gravity based on the Herglotz variational…

General Relativity and Quantum Cosmology · Physics 2026-03-20 Marek Wazny , Lehel Csillag , Miguel A. S. Pinto , Tiberiu Harko

We discuss the validity of the energy conditions in a newly modified theory named as $f(R,T,R_{\mu\nu}T^{\mu\nu})$ gravity, where $R$ and $T$ represent the scalar curvature and trace of the energy-momentum tensor. The corresponding energy…

General Relativity and Quantum Cosmology · Physics 2014-02-20 M. Sharif , M. Zubair

In literature there is a model of modified gravity in which the matter Lagrangian is coupled to the geometry via trace of the stress-energy momentum tensor $T=T_{\mu}^{\mu}$. This type of modified gravity is called as $f(R,T)$ in which $R$…

General Relativity and Quantum Cosmology · Physics 2016-08-30 M. J. S. Houndjo , M. E. Rodrigues , N. S. Mazhari , D. Momeni , R. Myrzakulov

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

We consider a gravitational model in which matter is non-minimally coupled to geometry, with the effective Lagrangian of the gravitational field being given by an arbitrary function of the Ricci scalar, the trace of the matter…

General Relativity and Quantum Cosmology · Physics 2024-11-18 Zahra Haghani , Tiberiu Harko , Francisco S. N. Lobo , Hamid Reza Sepangi , Shahab Shahidi

$f(R,T)$ gravity is a widely used extended theory of gravity introduced in \cite{9} which is a straightforward generalization of $f(R)$ gravity. The action in this extended theory of gravity incorporates well motivated functional forms of…

General Relativity and Quantum Cosmology · Physics 2020-07-09 Snehasish Bhattacharjee , P. K. Sahoo

We consider an extended theory of gravity with Lagrangian $\mathcal{L} = f(R,{\bf T}^{(n)})$, with ${\bf T}^{(n)}$ being a $2n$-th order invariant made of contractions of the energy-momentum tensor. When $n=1$ this theory reduces to…

General Relativity and Quantum Cosmology · Physics 2022-10-05 Habib Abedi , Francesco Bajardi , Salvatore Capozziello

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

We explore the generalized $f(R,T)$ modified theory of gravity, where the gravitational Lagrangian is a function of Ricci scalar $R$ and the trace of the energy-momentum tensor $T$. We derive modified field equations to the linear order of…

General Relativity and Quantum Cosmology · Physics 2024-10-29 Mahnaz Asghari , Ahmad Sheykhi

The aim of this paper is to introduce a new modified gravity theory named as $f(\mathcal{G},T)$ gravity ($\mathcal{G}$ and $T$ are the Gauss-Bonnet invariant and trace of the energy-momentum tensor, respectively) and investigate energy…

General Relativity and Quantum Cosmology · Physics 2016-12-21 M. Sharif , Ayesha Ikram

The $f(R,T)$ gravity field equations depend generically on both the Ricci scalar $R$ and trace of the energy-momentum tensor $T$. Within the assumption of perfect fluids, the theory carries an arbitrariness regarding the choice of the…

General Relativity and Quantum Cosmology · Physics 2019-09-04 P. H. R. S. Moraes

Gravitational baryogenesis is one of the mechanisms which help us to explore more about our early universe, especially baryon-anti-baryon asymmetry. As we know, modified theories of gravity are very successful in describing the present…

General Relativity and Quantum Cosmology · Physics 2023-05-23 Sai Swagat Mishra , Sanjay Mandal , P. K. Sahoo

A novel theory of $F(R)$ gravity with the Lagrangian density ${\cal L}=[R-(b/\beta)\arctan\left(\beta R\right)]/(2\kappa^2)$ is analyzed. Constant curvature solutions of the model are found, and the potential of the scalar field and the…

General Relativity and Quantum Cosmology · Physics 2014-03-07 S. I. Kruglov
‹ Prev 1 2 3 10 Next ›