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Related papers: Gravitational collapse and naked singularities

200 papers

Conditions under which gravity coupled to self interacting scalar field determines singularity formation are found and discussed. It is shown that, under a suitable matching with an external space, the boundary, if collapses completely, may…

General Relativity and Quantum Cosmology · Physics 2010-11-05 Roberto Giambó

We investigate the occurrence and nature of a naked singularity in the gravitational collapse of an inhomogeneous dust cloud described by a non self-similar higher dimensional Tolman spacetime. The necessary condition for the formation of a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 S G Ghosh , A Beesham

In this work we study collapse of a general matter in a most general spacetime i.e., a spacetime with any matter and without (assuming) any symmetry. We show that the energy is completely trapped inside the null singularity and therefore…

General Relativity and Quantum Cosmology · Physics 2010-12-15 Shrirang S. Deshingkar

We review here some recent developments on the issue of final fate of gravitational collapse within the framework of Einstein theory of gravity. The structure of collapsed object is discussed in terms of either a black hole or a singularity…

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

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

According to the cosmic censorship hypothesis of Penrose, naked singularities should never occur in realistic collapse situations. One of the major open problems in this context is the existence of a naked singularity in the Kerr solution…

General Relativity and Quantum Cosmology · Physics 2009-10-30 W. Rudnicki

A new mechanism for causing naked singularities is found in an effective superstring theory. We investigate the gravitational collapse in a spherically symmetric Einstein-Maxwell-dilaton system in the presence of a pure cosmological…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Kengo Maeda , Takashi Torii , Makoto Narita

We consider here the genericity aspects of spacetime singularities that occur in cosmology and in gravitational collapse. The singularity theorems (that predict the occurrence of singularities in general relativity) allow the singularities…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Pankaj S. Joshi

We investigate what are the key physical features that cause the development of a naked singularity, rather than a black hole, as the end-state of spherical gravitational collapse. We show that sufficiently strong shearing effects near the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Pankaj S. Joshi , Naresh Dadhich , Roy Maartens

We study the occurrence of naked singularities in the spherically symmetric collapse of radiation shells in a higher dimensional spacetime. The necessary conditions for the formation of a naked singularity or a black hole are obtained. The…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. G. Ghosh , R. V. Saraykar

We review the properties of naked time-like singularities in the General Relativity and quantum effects in their vicinity. We demonstrate that only line-like singularities can be formed by a collapse and are the only candidates to break the…

General Relativity and Quantum Cosmology · Physics 2012-09-18 Serge L. Parnovsky

The gravitational collapse of a thick cylindrical shell of dust matter is investigated. It is found that a spacetime singularity forms on the symmetry axis and that it is necessarily naked, i.e., observable in principle. We propose a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ken-ichi Nakao , Yasunari Kurita , Yoshiyuki Morisawa , Tomohiro Harada

We present here an overview of our basic understanding and recent developments on spacetime singularities in the Einstein theory of gravity. Several issues related to physical significance and implications of singularities are discussed.…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Pankaj S. Joshi

We investigate here quantum effects in gravitational collapse of a scalar field model which classically leads to a naked singularity. We show that non-perturbative semi-classical modifications near the singularity, based on loop quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Rituparno Goswami , Pankaj S. Joshi , Parampreet Singh

We construct here a class of collapsing scalar field models with a non-zero potential, which result in a naked singularity as collapse end state. The weak energy condition is satisfied by the collapsing configuration. It is shown that…

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

We study the gravitational collapse of a generalised Vaidya spacetime in the context of the Cosmic Censorship hypothesis. We develop a general mathematical framework to study the conditions on the mass function so that future directed…

General Relativity and Quantum Cosmology · Physics 2014-09-30 Maombi D. Mkenyeleye , Rituparno Goswami , Sunil D. Maharaj

A theorem, giving necessary and sufficient condition for naked singularity formation in spherically symmetric non static spacetimes under hypotheses of physical acceptability, is formulated and proved. The theorem relates existence of…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Roberto Giambo' , Fabio Giannoni , Giulio Magli , Paolo Piccione

This paper is a further development of the approach to weak cosmic censorship proposed by the authors in Ref. 5. We state and prove a modified version of that work's main result under significantly relaxed assumptions on the asymptotic…

General Relativity and Quantum Cosmology · Physics 2009-11-11 W. Rudnicki , R. J. Budzynski , W. Kondracki

Einstein's field equations in general relativity admit a variety of solutions with spacetime singularities. Numerical relativity has recently revealed the properties of somewhat generic spacetime singularities. It has been found that in a…

General Relativity and Quantum Cosmology · Physics 2009-08-18 Tomohiro Harada

We discuss several aspects of cosmic censorship hypothesis. There is evidence both in favor and against the hypothesis. On one hand one can prove that cosmic censorship holds in several special cases and on the other hand there is a number…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Andrzej Krolak