English
Related papers

Related papers: Gravastars with Dark Energy Evolving to Naked Sing…

200 papers

We numerically study the dynamics of an imploding hollow cylinder composed of dust. Since there is no cylindrical black hole in 4-dimensional spacetime with physically reasonable energy conditions, a collapsed dust cylinder involves a naked…

General Relativity and Quantum Cosmology · Physics 2009-11-19 Ken-ichi Nakao , Tomohiro Harada , Yasunari Kurita , Yoshiyuki Morisawa

We investigate the occurrence and nature of naked singularities in the gravitational collapse of an adiabatic perfect fluid in self-similar higher dimensional space-times. It is shown that strong curvature naked singularities could occur if…

General Relativity and Quantum Cosmology · Physics 2009-11-10 S. G. Ghosh , D. W. Deshkar

If an evaporating black hole does not settle down to a non radiating remnant, a description by a semi classical Lorentz metric must contain either a naked singularity or what we call a thunderbolt, a singularity that spreads out to infinity…

High Energy Physics - Theory · Physics 2010-11-01 S. W. Hawking , J. M. Stewart

The self-similar spherically symmetric perfect fluid space-time with scalar function incorporating linear equation of state is studied. The investigation of gravitational collapse conditions on the space-time determines that scalar function…

General Relativity and Quantum Cosmology · Physics 2021-03-09 Sanjay B. Sarwe , Gulshan O. Makkad

We adopt an effective action inspired by asymptotically safe gravity, in which the effective gravitational constant is parametrized as $G(\epsilon) = G_{N} /[1 + \tilde{\omega} (G_{N}^{2} \epsilon)^{\alpha}]$, where $G_{N}$ and $\epsilon$…

General Relativity and Quantum Cosmology · Physics 2025-06-18 Tomohiro Harada , Chiang-Mei Chen , Rituparna Mandal

Naked singularity occurs in the gravitational collapse of an inhomogeneous dust ball from an initial density profile which is physically reasonable. We show that explosive radiation is emitted during the formation process of the naked…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Tomohiro Harada , Hideo Iguchi , Ken-ichi Nakao

In this paper, we study the instability of naked singularities arising in the Einstein equations coupled with isothermal perfect fluid. We show that the spherically symmetric self-similar naked singularities of this system, are unstable to…

General Relativity and Quantum Cosmology · Physics 2025-05-28 Junbin Li , Xi-Ping Zhu

It is now known that when a massive star collapses under the force of its own gravity, the final fate of such a continual gravitational collapse will be either a black hole or a naked singularity under a wide variety of physically…

General Relativity and Quantum Cosmology · Physics 2012-04-20 Pankaj S. Joshi , Daniele Malafarina

Extending previous work on the formation and the evaporation of black holes in conformal gravity, in the present paper we study the gravitational collapse of a spherically symmetric and electrically charged thin shell of radiation. The…

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

Gravastars are configurations of compact singularity-free gravitational objects which are interesting alternatives to classical solutions in the strong gravitational field regime. Although there are no static star-like solutions of the…

General Relativity and Quantum Cosmology · Physics 2021-11-03 Alejandro Cabo Montes de Oca , Duvier Suarez Fontanella , David Valls-Gabaud

Recent developments on the final state of a gravitationally collapsing massive matter cloud are summarized and reviewed here. After a brief background on the problem, we point out how the black hole and naked singularity end states arise…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Pankaj S Joshi

This paper explores the possible existence of stable regions of bounded excursion gravastars in the background of regular black holes (Bardeen and Bardeen-de Sitter black holes). For this purpose, we match internal de Sitter geometry with…

General Relativity and Quantum Cosmology · Physics 2021-11-17 M. Sharif , Faisal Javed

In this article, we are reporting for the first time the existence of gravastar configurations in the framework of K(R,T)-gravity, which can be treated as an alternative to a black hole (Mazur and Mottola). This strengthens how much this…

General Relativity and Quantum Cosmology · Physics 2023-08-22 GRP Teruel , Ksh. Newton Singh , Tanmoy Chowdhury , Farook Rahaman , Monimala Mondal

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

In spherical symmetry, solutions of the semiclassical Einstein equations belong to one of two possible classes. Both classes contain solutions that -- depending on the dynamic behavior of the horizon -- describe evaporating physical black…

General Relativity and Quantum Cosmology · Physics 2022-03-10 Pravin K. Dahal , Sebastian Murk , Daniel R. Terno

We investigate a regular black hole model with a de Sitter-like core at its center. This type of a black hole model with a false vacuum core was introduced with the hope of singularity-resolution and is a common feature shared by many…

General Relativity and Quantum Cosmology · Physics 2020-08-12 Suddhasattwa Brahma , Dong-han Yeom

In this paper, we build a thin-shell gravastar model within a noncommutative BTZ geometry. For this, we consider a noncommutative BTZ metric in the inner region and a geometry associated with a BTZ solution in the outer region, joined by…

General Relativity and Quantum Cosmology · Physics 2024-04-03 A. T. N. Silva , M. A. Anacleto , L. Casarini

This paper studies the effects of charge on a peculiar stellar object, recognized as gravastar, under the influence of $f(R,T)$ gravity by considering the conjecture of Mazur and Mottola in general relativity. The gravastar is also known as…

General Relativity and Quantum Cosmology · Physics 2019-11-27 M. Sharif , Arfa Waseem

Gravastars have been recently proposed as potential alternatives to explain the astrophysical phenomenology traditionally associated to black holes, raising the question of whether the two objects can be distinguished at all. Leaving aside…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Cecilia B. M. H. Chirenti , Luciano Rezzolla

We study the collapse of a self-gravitating and radiating shell. Matter constituting the shell is quantized and the construction is viewed as a semiclassical model of possible black hole formation. It is shown that the shell internal…

General Relativity and Quantum Cosmology · Physics 2008-11-26 G. L. Alberghi , R. Casadio , G. P. Vacca , G. Venturi