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Related papers: Generic Naked Singularities in Vaidya Spacetimes

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We numerically investigate the gravitational collapse of collisionless particles in spheroidal configurations both in four and five-dimensional (5D) space-time. We repeat the simulation performed by Shapiro and Teukolsky (1991) that…

General Relativity and Quantum Cosmology · Physics 2011-03-21 Yuta Yamada , Hisa-aki Shinkai

We consider a static, axially symmetric, and asymptotically flat exact solution of the Einstein vacuum equations, known as the gamma metric. This is characterized by two constant parameters $m$ and $\gamma$. We find that the total energy…

General Relativity and Quantum Cosmology · Physics 2007-05-23 K. S. Virbhadra

We present a novel example of a 2-dimensional space-time naked singularity. The solution has a gravity singularity and no-horizon. This example is only a toy model and as such its motivation is mathematical. In the physical sense it is very…

General Relativity and Quantum Cosmology · Physics 2015-11-19 J. Manuel Garcia-Islas

Gravitational collapse is one of the most fruitful subjects in gravitational physics. It is well known that singularity formation is inevitable in complete gravitational collapse. It was conjectured that such a singularity should be hidden…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Tomohiro Harada , Hideo Iguchi , Ken-ichi Nakao

We investigate here the genericity and stability aspects for naked singularities and black holes that arise as the final states for a complete gravitational collapse of a spherical massive matter cloud. The form of the matter considered is…

General Relativity and Quantum Cosmology · Physics 2012-11-15 Pankaj S. Joshi , Daniele Malafarina , Ravindra V. Saraykar

We investigate the occurrence and nature of a naked singularity in the gravitational collapse of an inhomogeneous dust cloud described by higher dimensional Tolman-Bondi space-time. The naked singularities are found to be gravitationally…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ujjal Debnath , Subenoy Chakraborty

We study the formation of central naked singularities in spherical dust collapse with a cosmological constant. We find that the central curvature singularity is locally naked, Tipler strong, and generic, in the sense that it forms from a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Sergio M. C. V. Goncalves

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 study the occurrence and nature of naked singularities for a dust model with non-zero cosmological constant in ($n+2$)-dimensional Szekeres space-times (which possess no Killing vectors) for $n\geq 2$. We find that central shell-focusing…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Ujjal Debnath , Subenoy Chakraborty , John D. Barrow

We analyse here the gravitational collapse of directed null radiation in a background with a constant potential such as one produced by a star system like galaxy in which the collapsing object is immersed. Both naked singularities and black…

General Relativity and Quantum Cosmology · Physics 2009-10-31 S. Jhingan , N. Dadhich , P. S. Joshi

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

The existence of spacetime singularities is one of the biggest problems of nowadays physics. According to Penrose, each physical singularity should be covered by a "cosmic censor" which prevents any external observer from perceiving their…

General Relativity and Quantum Cosmology · Physics 2018-08-15 Alfio Bonanno , Benjamin Koch , Alessia Platania

A naked singularity occurs in the generic collapse of an inhomogeneous dust ball. We study the even-parity mode of gravitational waves from a naked singularity of the Lema\^{\i}tre-Tolman-Bondi spacetime. The wave equations for…

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

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 generalize here our earlier results on particle acceleration by naked singularities. We showed recently[1] that the naked singularities that form due to gravitational collapse of massive stars provide a suitable environment where…

General Relativity and Quantum Cosmology · Physics 2011-03-22 Mandar Patil , Pankaj S. Joshi , Daniele Malafarina

In the context of the large extra dimensions or TeV-scale gravity, it has been argued that an effective naked singularity, called the visible border of spacetime, would be generated by high-energy particle collisions. Motivated by this…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Masahiro Shimano , Umpei Miyamoto

Generalizing earlier results of Joshi and Dwivedi (Commun. Math. Phys. 146, 333 (1992); Lett. Math. Phys. 27, 235 (1993)), we analyze here the spherically symmetric gravitational collapse of a matter cloud with a general form of matter for…

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

Spacetime singularities have been discovered which are physically much weaker than those predicted by the classical singularity theorems. Geodesics evolve through them and they only display infinities in the derivatives of their curvature…

General Relativity and Quantum Cosmology · Physics 2015-12-09 John D. Barrow , Alexander A. H. Graham

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

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