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We discuss the gravitational collapse of spherical compact objects in the background of $f(R,T,Q)$ theory, where $R$ represent the Ricci scalar, $T$ is the trace of energy momentum tensor while $Q\equiv R_{\mu\nu}T^{\mu\nu}$, and…

General Relativity and Quantum Cosmology · Physics 2020-03-03 M. Z. Bhatti , Kazuharu Bamba , Z. Yousaf , M. Nawaz

In this paper, we explore the model of $f(Q,T)$ gravity, an extension of symmetric teleparallel gravity where the nonmetricity scalar $Q$ is non-minimally coupled to the trace of the energy-momentum tensor $T$. To ensure general covariance…

General Relativity and Quantum Cosmology · Physics 2025-09-09 Rahul Bhagat , Santosh V. Lohakare , B. Mishra

In the context of the late time cosmic acceleration phenomenon, many geometrically modified theories of gravity have been proposed in recent times. In this paper, we have investigated the role of a recently proposed extension of symmetric…

General Relativity and Quantum Cosmology · Physics 2021-08-16 A. S. Agrawal , Laxmipriya Pati , S. K. Tripathy , B. Mishra

In this work we examine the internal structure of compact stars within an extended gravitational framework described by the function $f(\mathcal{R},\mathcal{G},\mathcal{T})$. Throughout this work, the quantity $\mathcal{R}$ refers to the…

General Relativity and Quantum Cosmology · Physics 2025-11-25 G. G. L. Nashed

The basic aim of this manuscript is to investigate the cosmological solutions in the context of the modified $f(R, T)$ theory of gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor. For our current…

General Relativity and Quantum Cosmology · Physics 2024-03-26 Adnan Malik , Tayyaba Naz , Aimen Rauf , M. Farasat Shamir , Z. Yousaf

We assume cylindrically symmetric stars which begin collapsing by dissipating energy in the form of heat flux. We wish to study the effects of Carroll-Duvvuri-Trodden-Turner (CDTT) model, $f(R)=R+\sigma\frac{\mu^4}{R}$, on the range of…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Hafiza Rizwana Kausar

This paper is devoted to study the stability/instability of the expansionfree self gravitating source in the framework of Einstein Gauss-Bonnet gravity. The source has been taken as Tolman-Bondi model which is homogenous in nature. The…

General Relativity and Quantum Cosmology · Physics 2015-04-22 G. Abbas , S. Sarwar

In this paper, we examined the viability bounds of a higher derivative $f(R,\Box R, T)$ theory through analyzing energy conditions (where $R$ and $T$ are the Ricci scalar and trace of energy momentum tensor, respectively). We take flat…

General Relativity and Quantum Cosmology · Physics 2018-06-26 Z. Yousaf , M. Sharif , M. Ilyas , M. Z. Bhatti

This paper is devoted to investigate the cylindrical collapse of an anisotropic fluid in $f(R)$ gravity. For this purpose, the viscous charged anisotropic fluid dissipating energy with heat flow and shear is assumed. We use the perturbation…

General Relativity and Quantum Cosmology · Physics 2017-12-07 M. Farasat Shamir , M. Atif Fayyaz

This manuscript is devoted to study the combined effect of a viable model, f(R) = R + \alpha R^n, and electromagnetic field on the instability range of gravitational collapse. We assume charged anisotropic fluid that dissipate energy via…

General Relativity and Quantum Cosmology · Physics 2014-02-03 H. Rizwana Kausar , Ifra Noureen

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 discuss the collapsing and expanding solutions of anisotropic charged cylinder in the context of $f(R,T)$ theory ($R$ represents the Ricci scalar and $T$ denotes the trace of energy-momentum tensor). For this purpose, we take an…

General Relativity and Quantum Cosmology · Physics 2019-02-19 M. Sharif , Aisha Siddiqa

The aim of this paper is to generalize the definition of complexity for the static self-gravitating structure in $f(R,T,Q)$ gravitational theory, where $R$ is the Ricci scalar, $T$ is the trace part of energy momentum tensor and $Q\equiv…

General Relativity and Quantum Cosmology · Physics 2021-04-28 Z. Yousaf , Maxim Yu. Khlopov , M. Z. Bhatti , T. Naseer

In this study, we present a generalized spherically symmetric, anisotropic and static compact stellar model in $f(T)$ gravity, where $T$ represents the torsion scalar. By employing the Karmarkar condition we have obtained embedding class 1…

General Relativity and Quantum Cosmology · Physics 2018-11-30 Debabrata Deb , Shounak Ghosh , S. K. Maurya , Maxim Khlopov , Saibal Ray

The aim of this paper is to reconstruct and analyze the stability of some cosmological models against linear perturbations in $f(\mathcal{G},T)$ gravity ($\mathcal{G}$ and $T$ represent the Gauss-Bonnet invariant and trace of the…

General Relativity and Quantum Cosmology · Physics 2017-06-22 M. Sharif , Ayesha Ikram

This paper analyzes the anisotropic stellar evolution governed by a polytropic equation of state in the framework of $f(R,T,Q)$ gravity, where $Q=R_{ab}T^{ab}$. We construct the field equations, hydrostatic equilibrium equation and trace…

General Relativity and Quantum Cosmology · Physics 2019-02-19 M. Sharif , Arfa Waseem

This paper investigates the existence and stability of Einstein universe in the context of $f(R,T,Q)$ gravity, where $Q=R_{\mu\nu}T^{\mu\nu}$. Considering linear homogeneous perturbations around scale factor and energy density, we formulate…

General Relativity and Quantum Cosmology · Physics 2018-12-19 M. Sharif , Arfa Waseem

In this article, we examine the dynamical system of the $f(R,\mathcal{G})$ gravity model. This $f(R,G)$ model framework is composed of interactions between dark matter and scalar field through the linear coupling term. The key objective of…

General Relativity and Quantum Cosmology · Physics 2025-04-03 Shivani Sharma , R. Chaubey

The main purpose of this paper is to investigate the exact solutions of cylindrically symmetric 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…

General Relativity and Quantum Cosmology · Physics 2015-07-01 M. Farasat Shamir , Zahid Raza

$f(R,T)$ 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