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Related papers: Conformally Flat Collapsing Stars in f (R) gravity

200 papers

In the present paper we generate a set of solutions describing the interior of a compact star under $f(R,T)$ theory of gravity which admits conformal motion. We consider the equation of state (EOS) $p=\omega\rho$ with $0<\omega<1$ for the…

General Relativity and Quantum Cosmology · Physics 2016-12-20 Amit Das , Farook Rahaman , B. K. Guha , Saibal Ray

We study the formation and the evaporation of a spherically symmetric black hole in conformal gravity. From the collapse of a spherically symmetric thin shell of radiation, we find a singularity-free non-rotating black hole. This black hole…

General Relativity and Quantum Cosmology · Physics 2018-09-03 Cosimo Bambi , Leonardo Modesto , Shiladitya Porey , Leslaw Rachwal

This paper presents a hydrodynamic and thermodynamic treatment of a radiant star model that undergoes a dissipative gravitational collapse, from a certain initial configuration until it becomes a black hole. The collapsing star consists of…

General Relativity and Quantum Cosmology · Physics 2022-04-27 J. M. Z. Pretel , M. F. A. da Silva

The gravitational collapse of a star is a warmly discussed but still puzzling problem, which not only involves the dynamics of the gases, but also the subtle coordinate transformation. In this letter, we give some more detailed…

General Relativity and Quantum Cosmology · Physics 2009-04-30 Ying-Qiu Gu

In this paper we study the shear free spherical symmetric gravitational collapse of charged radiating star. All the physical quantities including pressure, density are regular. Energy conditions are satisfied throughout the interior of the…

General Relativity and Quantum Cosmology · Physics 2023-12-29 Suresh C. Jaryal , Ayan Chatterjee , Akshay Kumar

We consider a spherically symmetric stellar model in general relativity whose interior consists of a pressureless fluid undergoing microscopic velocity diffusion in a cosmological scalar field. We show that the diffusion dynamics compel the…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Artur Alho , Simone Calogero

We have proposed a model for relativistic compact star with anisotropy and analytically obtained exact spherically symmetric solutions describing the interior of the dense star admitting non-static conformal symmetry. Several features of…

General Relativity and Quantum Cosmology · Physics 2016-04-27 Dibyendu Shee , Farook Rahaman , B. K. Guha , Saibal Ray

Within the metric formalism of $f(R)$ theories of gravity, where $R$ is the Ricci scalar, we study the hydrostatic equilibrium structure of compact stars with the inclusion of anisotropic pressure. In particular, we focus on the $f(R)=…

General Relativity and Quantum Cosmology · Physics 2022-07-11 Juan M. Z. Pretel , Sergio B. Duarte

We present a class of exact solutions of Einstein field equations for a shear-free spherically symmetric anisotropic fluid undergoing radial heat flow. The interior metric fulfilled all the relevant physical and thermodynamic conditions and…

General Relativity and Quantum Cosmology · Physics 2016-01-21 B. C. Tewari , Kali Charan

Here we consider the generalized Oppenheimer-Snyder collapse of a star into a four-dimensional Einstein-Gauss-Bonnet black hole as well as a class of regular black holes labeled by the polytropic index of the stellar matter. We then analyze…

General Relativity and Quantum Cosmology · Physics 2024-10-01 A. Sadeghi , F. Shojai , F. Bahmani

We have found some new exact static spherically symmetric interior solutions of metric $f(R)$ gravitational theories describing the equilibrium configuration of a star. Then the solution is matched to the exterior solution and thus gives a…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Ali Shojai , Fatimah Shojai

In this work, we study the collapse dynamics of an inhomogeneous spherically symmetric star made of dark matter (DM) and dark energy (DE). The dark matter is taken in the form of a dust cloud while anisotropic fluid is chosen as the…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Subenoy Chakraborty , Tanwi Bandyopadhyay

The gravitational strength of the central singularity in spherically symmetric space-times is investigated. Necessary conditions for the singularity to be gravitationally weak are derived and it is shown that these are violated in a wide…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Brien C. Nolan

We investigate spherically symmetric gravitational collapse of thick matter shell without radiation in the Einstein gravity with cosmological constant. The orbit of the infalling thick matter is determined by imposing an equation of state…

General Relativity and Quantum Cosmology · Physics 2023-01-10 Shuichi Yokoyama

The $f(R)$ gravity models formulated in Einstein conformal frame are equivalent to Einstein gravity together with a minimally coupled scalar field. The scalar field couples with the matter sector and the coupling term is given by the…

General Relativity and Quantum Cosmology · Physics 2012-07-24 Yousef Bisabr

Here we study some general properties of spherical shear-free collapse. Its general solution when imposing conformal flatness is reobtained [1,2] and matched to the outgoing Vaidya spacetime. We propose a simple model satisfying these…

General Relativity and Quantum Cosmology · Physics 2008-11-26 L. Herrera , G. Le Denmat , N. O. Santos , A. Wang

The present analytical understanding on the nature of the singularities which form at the endstate of gravitational collapse of massive fluid bodies ("stars") is reviewed. Special emphasis is devoted to the issue of physical reasonability…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sanjay Jhingan , Giulio Magli

This paper aims to explore some realistic configurations of anisotropic spherical structures in the background of metric $f(R)$ gravity, where $R$ is the Ricci scalar. The solutions obtained by Krori and Barua are used to examine the nature…

General Relativity and Quantum Cosmology · Physics 2017-11-08 Z. Yousaf , M. Sharif , M. Ilyas , M. Z. Bhatti

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

A simple model of a spherically symmetric, pulsating star is calculated. The application to the Sun gives a 166-min radial pulsation. The theory of gravitation in flat space-time implies for a spherically symmetric, nonstationary star small…

General Physics · Physics 2010-02-09 Walter Petry