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Related papers: Gravastars in $f(R,G)$ Gravity

200 papers

Theories of gravity are fundamentally a relation between matter and the geometric structure of the underlying spacetime. So once we put some additional restrictions on the spacetime geometry, the theory of gravity is bound to get the…

General Relativity and Quantum Cosmology · Physics 2022-08-16 Tee-How Loo , Avik De , Simran Arora , P. K. Sahoo

This paper is devoted to investigate gravitational collapse of dust in metric $f(R)$ gravity. We take FRW metric for the interior region while the Schwarzchild spacetime is considered for the exterior region of a star. The junction…

General Relativity and Quantum Cosmology · Physics 2015-07-06 M. Farasat Shamir , Zahid Ahmad , Zahid Raza

In this paper, we have analyzed the geometrical and dynamical parameters of $\mathcal{F}(R, \mathcal{G})=\alpha R^2 \mathcal{G}^\beta$ cosmological model, ($R$, $\mathcal{G}$ being the Ricci scalar and Gauss-Bonnet invariant respectively),…

General Relativity and Quantum Cosmology · Physics 2023-10-11 Santosh V. Lohakare , Krishna Rathore , B. Mishra

In this paper, we study the dynamical behaviour of the Universe in the $F(R,G)$ theory of gravity, where $R$ and $G$ respectively denote the Ricci scalar and Gauss-Bonnet invariant. Our wide analysis encompasses the energy conditions,…

General Relativity and Quantum Cosmology · Physics 2022-04-22 Santosh V. Lohakare , S. K. Tripathy , B. Mishra

Recently, the scalar-tensor representation of $f (R,T)$ gravity was used to explore gravitationally induced particle production/annihilation. Using the framework of irreversible thermodynamics of open systems in the presence of matter…

General Relativity and Quantum Cosmology · Physics 2023-10-20 Amine Bouali , Himanshu Chaudhary , Tiberiu Harko , Francisco S. N. Lobo , Taoufik Ouali , Miguel A. S. Pinto

The present work discusses about the existence of compact star model in the context of $f(R,T)$ gravity with $R$ as the Ricci scalar and $T$ as the trace of energy-momentum tensor $T_{\mu \nu}$. The model has been developed by considering…

General Relativity and Quantum Cosmology · Physics 2021-07-05 Piyali Bhar , Pramit Rej , Aisha Siddiqa , Ghulam Abbas

In this manuscript, we have identified the dynamical instability constraints of a self-gravitating cylindrical object within the framework of $f(R,T)$ theory of gravity. We have explored the modified field equations and corresponding…

General Physics · Physics 2016-05-18 Z. Yousaf , M. Zaeem ul Haq Bhatti

Gravitational vacuum condensate stars, proposed as the endpoint of gravitational collapse consistent with quantum theory, are reviewed. Gravastars are cold, low entropy, maximally compact objects characterized by a surface boundary layer…

General Relativity and Quantum Cosmology · Physics 2023-11-28 Emil Mottola

The theory of gravity with a quadratic contribution of scalar curvature is investigated using a dynamical systems approach. The simplest Friedmann--Robertson--Walker metric is employed to formulate the dynamics in both the Jordan frame and…

General Relativity and Quantum Cosmology · Physics 2024-12-19 Orest Hrycyna

The objective of this research is to explore compact celestial objects while considering the framework of an extended gravitational theory known as $\mathcal{R}+f(\mathcal{G})$ gravity. The notations $\mathcal{R}$ and $\mathcal{G}$ denote…

General Relativity and Quantum Cosmology · Physics 2024-07-08 G. G. L. Nashed , Kazuharu Bamba

We consider the Palatini formulation of $f(R,T)$ gravity theory, in which a nonminimal coupling between the Ricci scalar and the trace of the energy-momentum tensor is introduced, by considering the metric and the affine connection as…

General Relativity and Quantum Cosmology · Physics 2018-07-24 Jimin Wu , Guangjie Li , Tiberiu Harko , Shi-Dong Liang

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

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

We calculate static and spherically symmetric solutions for the Rastall modification of gravity to describe Neutron Stars (NS). The key feature of the Rastall gravity is the non-conservation of the energy-momentum tensor proportionally to…

General Relativity and Quantum Cosmology · Physics 2016-10-24 A. M. Oliveira , H. E. S. Velten , J. C. Fabris , L. Casarini

We study thin shells of matter in (2+1)-dimensional F(R) theories of gravity with constant scalar curvature R. We consider a wide class of spacetimes with circular symmetry, in which a thin shell joins an inner region with an outer one. We…

General Relativity and Quantum Cosmology · Physics 2021-02-10 Ernesto F. Eiroa , Griselda Figueroa-Aguirre

We develop a static charged stellar model in $f(R,T)$ gravity where the modification is assumed to be linear in $T$ which is the trace of the energy momentum tensor. The exterior spacetime of the charged object is described by the…

General Relativity and Quantum Cosmology · Physics 2023-11-07 Soumik Bhattacharya , Ranjan Sharma , Sunil D. Maharaj

A modified theory of gravity with the function $F(R) = R\exp(\alpha R)$ instead of Ricci scalar $R$ in the Einstein$-$Hilbert action is considered and analyzed. The action of the model is converted into Einstein$-$Hilbert action at small…

General Relativity and Quantum Cosmology · Physics 2013-09-30 S. I. Kruglov

We present a comprehensive theoretical framework for gravitational wave (GW) propagation and their \textbf{nonlinear backreaction} in $f(R, G)$ modified gravity. By developing a scalar-tensor formulation with two auxiliary fields, we…

General Relativity and Quantum Cosmology · Physics 2025-12-30 Farzad Milani

The present study provides an in-depth analysis of the anisotropic matter distribution and various physical aspects of compact stars in the context of a $f(R,G)$-gravity framework. In order to gain an exhaustive understanding of these…

General Relativity and Quantum Cosmology · Physics 2023-08-22 M. Ilyas , A. R. Athar , F. Khan , Asma Anfal

The main goal of this work is to provide a comprehensive study of relativistic structures in the context of recently proposed {$\mathcal{R}+ \alpha \mathcal{A}$} gravity, where $\mathcal{R}$ is the Ricci scalar, and $\mathcal{A}$ is the…

General Relativity and Quantum Cosmology · Physics 2023-04-11 M. Farasat Shamir , Eesha Meer