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In this research work, we explore the late-time accelerated expansion of the universe within the framework of modified gravity, specifically $f(R, L_m)$ theory, by considering two non-linear models: $f(R, L_{m}) = \frac{R}{2}+(1+\eta R)…

General Relativity and Quantum Cosmology · Physics 2025-06-23 Khomesh R. Patle , G. P. Singh , Romanshu Garg

In this paper, we consider a theory of gravity with a metric-dependent torsion namely the $F(R,T)$ gravity, where $R$ is the curvature scalar and $T$ is the torsion scalar. We study a geometric root of such theory. In particular we give the…

General Relativity and Quantum Cosmology · Physics 2012-11-20 Ratbay Myrzakulov

This paper explores the dark energy phenomenon within the context of $f(R,L_m)$ gravity theory. Two specific non-linear $f (R, L_m)$ models are considered: $f(R,L_m)=\frac{R}{2}+L_m^\alpha$ and $f(R,L_m)=\frac{R}{2}+(1+\alpha R)L_m$, where…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-13 S. Myrzakulova , M. Koussour , N. Myrzakulov

The present study reexamines the recent work of Pradhan et al. (Indian J. Phys. 88: 757, 2014) and obtained general exact solutions of the Einstein's field equations with variable gravitational and cosmological "constants" for a spatially…

General Physics · Physics 2015-08-06 Anirudh Pradhan , Bijan Saha , Victor Rikhvitsky

In this paper, we study the cosmological evolution of a viscous dark energy model within the framework of $f(Q, C)$ gravity, utilizing a two-fluid approach. The model incorporates non-metricity and boundary contributions to the total…

General Relativity and Quantum Cosmology · Physics 2025-10-15 N. Myrzakulov , Anirudh Pradhan , S. H. Shekh

In this paper, we investigate the cosmological implications and constraints of Weyl-type $f(Q, T)$ gravity. This theory introduces a coupling between the non-metricity $Q$ and the trace $T$ of the energy-momentum tensor, using the…

General Relativity and Quantum Cosmology · Physics 2024-03-27 Alnadhief H. A. Alfedeel , M. Koussour , N. Myrzakulov

In the present article, we developed a dynamical system in the context of modified $f(R,G,T)$ gravity, where $R$, $G$ and $T$ are Ricci scalar, Gauss-Bonnet term and energy-momentum tensor respectively. Development of the dynamical system…

General Relativity and Quantum Cosmology · Physics 2025-05-30 Elangbam Chingkheinganba Meetei , S. Surendra Singh

In this paper we consider FRW cosmology in $F(R,\phi)$ gravity. It is shown that in particular cases the bouncing behavior may appears in the model whereas the equation of state (EoS) parameter may crosses the phantom divider. For the…

General Physics · Physics 2015-03-17 H. Farajollahi , M. Setare , F. Milani , F. Tayebi

The problem of cosmic acceleration and dark energy is one of the mysteries presently posed in the scientific society that general relativity has not been able to solve. In this work, we have considered alternative models to explain this…

General Relativity and Quantum Cosmology · Physics 2022-12-01 M. Koussour , N. Myrzakulov , S. H. Shekh , M. Bennai

This paper is devoted to investigate the exact solutions of Bianchi type $I$ spacetime in the context of $f(R,T)$ gravity [1], where $f(R,T)$ is an arbitrary function of Ricci scalar $R$ and trace of the energy momentum tensor $T$. For this…

General Relativity and Quantum Cosmology · Physics 2015-06-30 M. Farasat Shamir

In this study, we investigate strange quark stars within the framework of modified $f(R,T)$ gravity, where $R$ represents the Ricci scalar and $T$ denotes the trace of the energy-momentum tensor, specifically defined as $ f(R,T) = R + 2\chi…

General Relativity and Quantum Cosmology · Physics 2024-10-08 Suman Pal , Gargi Chaudhuri

This study investigates the cosmological implications of $f(R,\Sigma,T)$ gravity by reconstructing the Hubble parameter from a logarithmic parameterization of the $O_m(z)$ diagnostic. Our approach offers a model-independent way to probe the…

General Relativity and Quantum Cosmology · Physics 2026-05-12 N. Myrzakulov , Anirudh Pradhan , Anil Kumar Yadav , S. H. Shekh

In this article, we investigate scalar field cosmology in the coincident $f(Q)$ gravity formalism. We calculate the motion equations of $f(Q)$ gravity under the flat Friedmann-Lema\^{i}tre-Robertson-Walker background in the presence of a…

General Relativity and Quantum Cosmology · Physics 2024-04-12 Sayantan Ghosh , Raja Solanki , P. K. Sahoo

The $f(R,T)$ gravity models, for which $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor, elevate the degrees of freedom of the renowned $f(R)$ theories, by making the Einstein field equations of the theory to also…

General Relativity and Quantum Cosmology · Physics 2024-02-28 J. A. S. Fortunato , P. H. R. S. Moraes , J. G. de Lima Júnior , E. Brito

In this work we have investigated the dynamics of a recent modification to the general theory of relativity, the energy-momentum squared gravity model $f(R,\mathbf{T^2})$, where $R$ represents the scalar curvature and $\mathbf{T^2}$ the…

General Relativity and Quantum Cosmology · Physics 2019-10-16 Sebastian Bahamonde , Mihai Marciu , Prabir Rudra

To find more deliberate f(R,T) cosmological solutions, we proceed our previous paper further by studying some new aspects of the considered models via investigation of some new cosmological parameters/quantities to attain the most…

General Relativity and Quantum Cosmology · Physics 2017-05-23 Hamid Shabani , Mehrdad Farhoudi

We investigate cosmological solutions of f(R,T) modified theories of gravity for perfect fluid in spatially FLRW metric through phase space analysis, where R is Ricci scalar and T denotes the trace of energy-momentum tensor of matter…

General Relativity and Quantum Cosmology · Physics 2017-05-23 Hamid Shabani , Mehrdad Farhoudi

In this paper, we present an accelerating cosmological model by constraining the free parameters using the cosmological datasets in an extended symmetric teleparallel gravity for the flat and anisotropic space-time. We employ a time…

General Relativity and Quantum Cosmology · Physics 2023-06-27 S. A. Narawade , M. Koussour , B. Mishra

In this study, we analyze the anisotropic universe in $f(Q,C)$ gravity theory. To achieve this, we consider three specific models of $f(Q,C)$ gravity and rewrite the equations of motion of each model as an autonomous system. We identify and…

General Relativity and Quantum Cosmology · Physics 2025-05-14 Ghulam Murtaza , Avik De , Tee-How Loo , Yong Kheng Goh , How Hui Liew

In this article, the bulk viscosity is introduced in a modified gravity model. The gravitational action has a general $f(R,T)$ form, where $R$ and $ T $ are the curvature scalar and the trace of energy momentum tensor respectively. An…

General Relativity and Quantum Cosmology · Physics 2020-10-02 Simran Arora , Xin-he Meng , S. K. J. Pacif , P. K. Sahoo