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Related papers: Naked Singularities as Particle Accelerators II

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It has been shown that black holes could be used as particle accelerators to create arbitrarily high center-of-mass (CM) energy if certain critical conditions are satisfied. Most studies so far are confined in four-dimensional spacetimes.…

General Relativity and Quantum Cosmology · Physics 2017-09-01 Jincheng An , Sijie Gao

At the threshold of black hole formation in the gravitational collapse of a scalar field a naked singularity is formed through a universal critical solution that is discretely self-similar. We study the global spacetime structure of this…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Jose M. Martin-Garcia , Carsten Gundlach

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

A distinguishable and observable physical property of Naked Singular Regions of the spacetime formed during a gravitational collapse has important implications for both experimental and theoretical relativity. We examine here whether energy…

General Relativity and Quantum Cosmology · Physics 2011-08-08 S. Jhingan , I. H. Dwivedi , S. Barve

Considering the evolution of a perfect fluid with self-similarity of the second kind, we have found that an initial naked singularity can be trapped by an event horizon due to collapsing matter. The fluid moves along time-like geodesics…

General Relativity and Quantum Cosmology · Physics 2012-10-25 C. F. C. Brandt , R. Chan , M. F. A. da Silva , J. F. Villas da Rocha

Assuming the weak energy condition, we study the nature of the non-central shell-focussing singularity which can form in the gravitational collapse of a spherical compact object in classical general relativity. We show that if the radial…

General Relativity and Quantum Cosmology · Physics 2009-10-28 F. I. Cooperstock , S. Jhingan , P. S. Joshi , T. P. Singh

An outstanding problem in gravitation theory and relativistic astrophysics today is to understand the final outcome of an endless gravitational collapse. Such a continual collapse would take place when stars more massive than few times the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Pankaj S. Joshi

Primordial black hole formation has been discussed widely, when density perturbations in the early universe cause matter to collapse gravitationally, giving rise to these ultra-compact objects. We propose and point out that such a…

General Relativity and Quantum Cosmology · Physics 2024-12-17 Pankaj S. Joshi , Sudip Bhattacharyya

In this paper, we study the gravitational collapse of null dust in the cylindrically symmetric spacetime. The naked singularity necessarily forms at the symmetry axis. We consider the situation in which null dust is emitted again from the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Yasunari Kurita , Ken-ichi Nakao

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

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

We study the final outcome of gravitational collapse resulting from the plane symmetric charged Vaidya spacetime. Using the field equations, we show that the weak energy condition is always satisfied by collapsing fluid. It is found that…

General Relativity and Quantum Cosmology · Physics 2011-03-17 M. Sharif , Aisha Siddiqa

A strong gravity naked singular region can give important clues towards understanding classical as well as spontaneous nature of General Relativity. We propose here a model for energy emission from a naked singular region in a self-similar…

General Relativity and Quantum Cosmology · Physics 2018-05-23 Takafumi Kokubu , Sanjay Jhingan , Tomohiro Harada

We study the complete gravitational collapse of a class of spherically symmetric inhomogeneous perfect fluid models obtained by introducing small radial perturbations in an otherwise homogeneous matter cloud. Our aim here is to study the…

General Relativity and Quantum Cosmology · Physics 2016-03-10 Seema Satin , Daniele Malafarina , Pankaj S. Joshi

Possibilities emerging out of the dynamical evolutions of collapsing systems are addressed in this thesis through analytical investigations of the highly non-linear Einstein Field Equations. Studies of exact solutions and their properties,…

General Relativity and Quantum Cosmology · Physics 2017-09-07 Soumya Chakrabarti

We derive an equation for the acceleration of a fluid element in the spherical gravitational collapse of a bounded compact object made up of an imperfect fluid. We show that non-singular as well as singular solutions arise in the collapse…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Sukratu Barve , T. P. Singh , Louis Witten

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 stability of occurrence of black holes and naked singularities that arise as a final state for a complete gravitational collapse of type I matter field in a spherically symmetric $N$ dimensional spacetime with equation of state $p…

General Relativity and Quantum Cosmology · Physics 2014-11-26 Sanjay Sarwe , R. V. Saraykar

We analytically investigate the pertubative effects of a quantum conformally-coupled scalar field on rotating (2+1)-dimensional black holes and naked singularities. In both cases we obtain the quantum-backreacted metric analytically. In the…

High Energy Physics - Theory · Physics 2019-05-22 Marc Casals , Alessandro Fabbri , Cristián Martínez , Jorge Zanelli

Particle collisions are considered within the context of $f(R)$ gravity described by $f(R)=R+2\alpha\sqrt{R}$, where $R$ stands for the Ricci scalar and $\alpha$ is a non-zero constant. The center of mass (CM) energy of head-on colliding…

General Relativity and Quantum Cosmology · Physics 2017-11-16 M. Halilsoy , A. Ovgun