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

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We derive a new interior solution for stellar compact objects in $f\mathcal{(R)}$ gravity assuming a differential relation to constrain the Ricci curvature scalar. To this aim, we consider specific forms for the radial component of the…

General Relativity and Quantum Cosmology · Physics 2021-06-03 G. G. L. Nashed , S. Capozziello

We investigate gravitational collapse of thick shell of fluid in the isotropic homogeneous universe without radiation described by the Einstein gravity with cosmological constant. We construct analytic solutions of this kind interpolating…

General Relativity and Quantum Cosmology · Physics 2022-09-07 Shuichi Yokoyama

Complete tensor-scalar and hydrodynamic equations are presented and integrated, for a self-gravitating perfect fluid. The initial conditions describe unstable-equilibrium neutron star configuration, with a polytropic equation of state. They…

General Relativity and Quantum Cosmology · Physics 2009-10-30 J. Novak

A new class of self-gravitating collapsing star models with perfect fluid distributions is discussed in this work. The paper has a comprehensive analysis of a homogeneous gravitational collapsing system wherein using a parametrization…

General Relativity and Quantum Cosmology · Physics 2023-03-14 Annu Jaiswal , Rajesh Kumar , Sudhir Kumar Srivastava , S. K. J. Pacif

General relativity can be formulated equivalently with a non-Riemannian geometry that associates with an affine connection of nonzero nonmetricity $Q$ but vanishing curvature $R$ and torsion $T$. Modification based on this description of…

General Relativity and Quantum Cosmology · Physics 2021-06-16 Rui-Hui Lin , Xiang-Hua Zhai

We study the spherical gravitational collapse of a compact object under the approximation that the radial pressure is identically zero, and the tangential pressure is related to the density by a linear equation of state. It turns out that…

General Relativity and Quantum Cosmology · Physics 2009-10-30 T. P. Singh , Louis Witten

Various types of inhomogeneous collapse models in general relativity (GR) lead to the formation of spacetime singularities either visible or hidden by a spacetime horizon. Our aim in the present work is to search for nonsingular models in…

General Relativity and Quantum Cosmology · Physics 2025-07-04 Akbar Jahan , Halime Miraghaei , Shayesteh Ghaffari , Amir Hadi Ziaie

In this work, the collapsing process of a spherically symmetric star, made of dust cloud, is studied in Ho\v{r}ava Lifshitz gravity in the background of Chaplygin gas dark energy. Two different classes of Chaplygin gas, namely, New variable…

General Physics · Physics 2014-05-30 Prabir Rudra , Ujjal Debnath

Time evolution of an optical image of a pressureless star under gravitational collapse is studied in the geometric optics approximation. The star surface is assumed to emit radiation obeying Lambert's cosine law but with an arbitrary…

General Relativity and Quantum Cosmology · Physics 2019-11-04 Hirotaka Yoshino , Kazuma Takahashi , Ken-ichi Nakao

We study the interior spacetimes of stars in the Palatini formalism of f(R) gravity and derive a generalized Tolman-Oppenheimer-Volkoff and mass equation for a static, spherically symmetric star. We show that matching the interior solution…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Kimmo Kainulainen , Vappu Reijonen , Daniel Sunhede

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

We study the gravitational collapse in modified gravitational theories. In particular, we analyze a general $f(R)$ model with uniformly collapsing cloud of self-gravitating dust particles. This analysis shares analogies with the formation…

General Relativity and Quantum Cosmology · Physics 2015-06-03 J. A. R. Cembranos , A. de la Cruz-Dombriz , B. Montes Nuñez

We investigate the gravitational collapse of a spherically symmetric, inhomogeneous star, which is described by a perfect fluid with heat flow and satisfies the equation of state $p=\rho/3$ at its center. In the process of the gravitational…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Zhe Chang , Cheng-Bo Guan , Chao-Guang Huang , Xin Li

It is shown that a scalar field, minimally coupled to gravity may have collapsing modes even when the energy condition is violated, that is, for $(\rho+3p)<0$. This result may be useful in the investigation of the possible clustering of…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Koyel Ganguly , Narayan Banerjee

We consider here the effects of a non-vanishing cosmological term on the final fate of a spherical inhomogeneous collapsing dust cloud. It is shown that depending on the nature of the initial data from which the collapse evolves, and for a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 S. S. Deshingkar , S. Jhingan , A. Chamorro , P. S. Joshi

A spherically symmetric collapsing scalar field model is discussed with a dissipative fluid which includes a heat flux. This vastly general matter distribution is analyzed at the expense of a high degree of symmetry in the space-time, that…

General Relativity and Quantum Cosmology · Physics 2017-01-17 Narayan Banerjee , Soumya Chakrabarti

We investigate anisotropic compact stars in the non-minimal $Y(R)F^2$ model of gravity which couples an arbitrary function of curvature scalar $Y(R)$ to the electromagnetic field invariant $F^2$. After we obtain exact anisotropic solutions…

General Relativity and Quantum Cosmology · Physics 2018-10-17 Özcan Sert , Fatma Çeliktaş , Muzaffer Adak

We review a series of recent results on global dynamic properties of radially symmetric self-gravitating compressible Euler flows, which naturally arise in the mathematical description of stars. We focus on the role of scaling invariances…

Analysis of PDEs · Mathematics 2023-06-06 Mahir Hadzic

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

We investigate the fate of a collapsing stellar core, which is the final state of evolution of a massive, rotating star of a Wolf-Rayet type. Such stars explode as type I b/c supernovae, which have been observed in association with long…

High Energy Astrophysical Phenomena · Physics 2024-01-31 Agnieszka Janiuk , Narjes Shahamat , Dominika Król
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