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Related papers: Naked singularities and Seifert's conjecture

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Global visibility of naked singularities is analyzed here for a class of spherically symmetric spacetimes, extending previous studies - limited to inhomogeneous dust cloud collapse - to more physical valid situations in which pressures are…

General Relativity and Quantum Cosmology · Physics 2009-11-11 R. Giambo'

Exact solutions of the gravitational field equations for a mixture of a null charged strange quark fluid and radiation are obtained in a Vaidya space-time. The conditions for the formation of a naked singularity are analyzed by considering…

General Relativity and Quantum Cosmology · Physics 2009-11-07 T. Harko , K. S. Cheng

The phase space corresponding to a particular four-parameter family of initial data for the gravitational collapse of a spherically symmetric dust cloud is investigated. In a certain limit of the parameters, this family reproduces the case…

General Relativity and Quantum Cosmology · Physics 2015-03-20 Néstor Ortiz

Spherically symmetric inhomogeneous dust collapse has been studied in higher dimensional space-time and appearance of naked singularity has been analyzed both for non-marginal and marginally bound cases. It has been shown that naked…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Ujjal Debnath , Subenoy Chakraborty

In this article, we discuss four dimensional non-static space-times in the background of de-Sitter and anti-de Sitter spaces with the matter-energy sources a stiff fluid, anisotropic fluid, and an electromagnetic field. Under various…

General Relativity and Quantum Cosmology · Physics 2019-01-30 Faizuddin Ahmed , Farook Rahaman , Susmita Sarkar

It is known that the gravitational collapse of a dust ball results in naked singularity formation from an initial density profile which is physically reasonable. In this paper, we show that explosive radiation is emitted during the…

General Relativity and Quantum Cosmology · Physics 2009-12-30 Tomohiro Harada , Hideo Iguchi , Ken-ichi Nakao

We study singularities which can form in a spherically symmetric gravitational collapse of a general matter field obeying weak energy condition. We show that no energy can reach an outside observer from a null naked singularity. That means…

General Relativity and Quantum Cosmology · Physics 2010-02-17 Shrirang S. Deshingkar

We study here the structure of singularity forming in gravitational collapse of spherically symmetric inhomogeneous dust. Such a collapse is described by the Tolman-Bondi-Lema{\^i}tre metric, which is a two-parameter family of solutions to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. Jhingan , P. S. Joshi

By imposing suitable junction conditions on a space-like hyper-surface, we obtain a two-parameter family of possible static configurations from gravitational collapse. These exemplify a new class of naked singularities. We show that these…

General Relativity and Quantum Cosmology · Physics 2020-02-11 Kaushik Bhattacharya , Dipanjan Dey , Arindam Mazumdar , Tapobrata Sarkar

We investigate here the final state of gravitational collapse of a non-spherical and non-marginally bound dust cloud as modeled by the Szekeres spacetime. We show that a directionally globally naked singularity can be formed in this case…

General Relativity and Quantum Cosmology · Physics 2022-05-25 Dipanjan Dey , Pankaj S. Joshi , Karim Mosani , Vitalii Vertogradov

We study an analytical solution to the Einstein's equations in 2+1-dimensions, representing the self-similar collapse of a circularly symmetric, minimally coupled, massless, scalar field. Depending on the value of certain parameters, this…

General Relativity and Quantum Cosmology · Physics 2014-11-17 G. Oliveira-Neto

We study the occurrence, visibility, and curvature strength of singularities in dust-containing Szekeres spacetimes (which possess no Killing vectors) with a positive cosmological constant. We find that such singularities can be locally…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sergio M. C. V. Goncalves

One or two negative mass singularities are found to occur in static inhomogeneous spatially closed solutions to the Einstein equations. The singularities produce a positive Komar mass, and this decreases the size of the cosmological…

General Relativity and Quantum Cosmology · Physics 2026-04-29 Bob Holdom

Gravitational collapse of a spherically symmetric cloud has been extensively studied to investigate the nature of resulting singularity. However, there has been considerable debate about the admissibility of certain initial density…

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. M. Antia

There are non-radial null geodesics emanating from the shell focusing singularity formed at the symmetric center in a spherically symmetric dust collapse. In this article, assuming the self-similarity in the region filled with the dust…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Ken-ichi Nakao , Naoki Kobayashi , Hideki Ishihara

We find an exact solution in dimensionally continued gravity in arbitrary dimensions which describes the gravitational collapse of a null dust fluid. Considering the situation that a null dust fluid injects into the initially anti-de Sitter…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Masato Nozawa , Hideki Maeda

Roughly speaking, naked singularities are singularities that may be seen by timelike observers. The Cosmic Censorship conjecture forbids their existence by stating that a reasonable system of energy will not, under reasonable conditions,…

High Energy Physics - Theory · Physics 2009-10-30 Cenalo Vaz , Louis Witten

A distinguishable physical property between a naked singularity and a black-hole, formed during a gravitational collapse has important implications for both experimental and theoretical relativity. We examine the energy radiated during the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 I. H. Dwivedi

We calculate the quantum stress tensor for a massless scalar field in the 2-d self-similar spherical dust collapse model which admits a naked singularity. We find that the outgoing radiation flux diverges on the Cauchy horizon. This may…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Sukratu Barve , T. P. Singh , Cenalo Vaz , Louis Witten

Generalizing the results of Joshi and Dwivedi in Commun.Math.Phys. 146, p.333 (1992), it is pointed out that strong curvature naked singularities could occur in the self-similar gravitational collapse of any form of matter satisfying the…

General Relativity and Quantum Cosmology · Physics 2009-10-22 P. S. Joshi , I. H. Dwivedi