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Related papers: Naked Singularities as Particle Accelerators II

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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

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

In the final stages of collapse, quantum radiation due to particle creation from a naked singularity is expected to be significantly different from black hole radiation. In certain models of collapse it has been shown that, neglecting the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Cenalo Vaz , Louis Witten

We investigate here the locally naked singularity formed due to a spherically symmetric inhomogeneous collapsing cloud having non-zero isotropic pressure, in terms of its strength. Sufficient condition provided by Clarke and Krolak for it…

General Relativity and Quantum Cosmology · Physics 2020-03-04 Karim Mosani , Dipanjan Dey , Pankaj S. Joshi

We construct an approximate solution which describes the gravitational emission from a naked singularity formed by the gravitational collapse of a cylindrical thick shell composed of dust. The assumed situation is that the collapsing speed…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Ken-ichi Nakao , Yoshiyuki Morisawa

Dynamical evolution of test fields in background geometry with a naked singularity is an important problem relevant to the Cauchy horizon instability and the observational signatures different from black hole formation. In this paper we…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Eiji Mitsuda , Hirotaka Yoshino , Akira Tomimatsu

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

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

We give a characterization of the central shell-focusing curvature singularity that can form in the spherical gravitational collapse of a bounded matter distribution obeying the dominant energy condition. This characterization is based on…

General Relativity and Quantum Cosmology · Physics 2009-10-31 T. P. Singh

We show that all known naked singularities in spherically symmetric self-similar spacetimes arise as a result of singular initial matter distribution. This is a result of the peculiarity of the coordinate transformation that takes these…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sanjay M. Wagh , Keshlan S. Govinder

We consider collision of two geodesic particles near the horizon of such an axially symmetric black hole (rotating or static) that the metric coefficient $g_{\phi \phi }\rightarrow 0$ there. It is shown that (both for regular and singular…

General Relativity and Quantum Cosmology · Physics 2016-09-07 O. B. Zaslavskii

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 consider stationary axially symmetric black holes with the background scalar field and test particles that can interact with this field directly. Then, particle collision near a black hole can lead to the unbounded energy $% E_{c.m.}$ in…

General Relativity and Quantum Cosmology · Physics 2017-09-22 O. B. Zaslavskii

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

Spacetime singularities pose a long-standing puzzle in quantum gravity. Unlike Schwarzschild, a generic family of black holes gives rise to a Cauchy horizon on which, even in the Hartle-Hawking state, quantum observables such as $\langle…

High Energy Physics - Theory · Physics 2024-11-20 Arvin Shahbazi-Moghaddam

We consider a spherically symmetric homogeneous perfect fluid undergoing a gravitational collapse to singularity in the framework of higher-dimensional Rastall gravity in the cases of vanishing and nonvanishing cosmological constants. The…

General Relativity and Quantum Cosmology · Physics 2025-04-08 Golfin Ekatria , Andy Octavian Latief , Fiki Taufik Akbar , Bobby Eka Gunara

Cosmic censorship conjecture takes a pivotal status in general relativity. We demonstrate that quantum effects, Hawking effect together with Shwinger effect inevitably lead to violation of cosmic censorship. We find that naked singularity…

General Relativity and Quantum Cosmology · Physics 2025-07-01 Yang Huang , Hongsheng Zhang

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

A spacetime singularity, identified by the existence of incomplete causal geodesics in the spacetime, is called a (Tipler) strong curvature singularity if the volume form acting on independent Jacobi fields along causal geodesics vanishes…

General Relativity and Quantum Cosmology · Physics 2025-02-03 Kharanshu N. Solanki , Karim Mosani , Omkar Deshpande , Pankaj S. Joshi

High-energy astrophysical sources such as active galactic nuclei, quasars, X-ray binaries, and gamma-ray bursts are powered by mechanisms that convert gravitational or rotational energy into radiation, jets, and relativistic outflows.…

High Energy Astrophysical Phenomena · Physics 2025-12-03 Parth Bambhaniya , Elisabete M. de Gouveia Dal Pino