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Related papers: Naked Singularities as Particle Accelerators II

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We develop here a new procedure within Einstein's theory of gravity to generate equilibrium configurations that result as the final state of gravitational collapse from regular initial conditions. As a simplification, we assume that the…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Pankaj S. Joshi , Daniele Malafarina , Ramesh Narayan

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 investigate a vacuum decay around an over-spinning naked singularity by using the Israel junction condition. We found that if the Higgs field develops the second minimum at higher energy scale, a spinning small-mass naked singularity…

High Energy Physics - Theory · Physics 2020-03-09 Naritaka Oshita

Nowadays, the effect of infinite energy in the centre of mass frame due to near-horizon collisions attracts much attention.We show generality of the effect combining two seemingly completely different approaches based on properties of a…

General Relativity and Quantum Cosmology · Physics 2015-05-28 O. B. Zaslavskii

A massive naked singularity would be cloaked by accreted matter, and thus may appear to a distant observer as an opaque \mbox{(quasi-)}spherical surface of a fluid, not unlike that of a star or planet. We present here analytical solutions…

High Energy Astrophysical Phenomena · Physics 2023-06-30 Ronaldo S. S. Vieira , Włodek Kluźniak

We show that, in principle, a slowly evolving gravitationally collapsing perfect fluid cloud can asymptotically settle to a static spherically symmetric equilibrium configuration with a naked singularity at the center. We consider one such…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Pankaj S. Joshi , Daniele Malafarina , Ramesh Narayan

We consider near-horizon collisions between two particles moving freely in the Schwarzschild metric in the region outside the horizon. One of them emerges from a white hole. We scrutiny when such a process can lead to the indefinitely large…

General Relativity and Quantum Cosmology · Physics 2025-06-23 A. V. Toporensky , O. B. Zaslavskii

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 analyze here the issue of local versus the global visibility of a singularity that forms in gravitational collapse of a dust cloud, which has important implications for the weak and strong versions of the cosmic censorship hypothesis. We…

General Relativity and Quantum Cosmology · Physics 2015-06-25 S. S. Deshingkar , S. Jhingan , P. S. Joshi

Classical critical collapse yields naked singularities from smooth initial data, challenging cosmic censorship, and shaping the spectrum of primordial black holes. We show that one-loop vacuum polarization near the threshold qualitatively…

General Relativity and Quantum Cosmology · Physics 2026-05-18 Marija Tomašević , Chih-Hung Wu

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 investigate collapse of a spherical cloud of counter-rotating particles. An explicit solution is given using an elliptic integral. If the specific angular momentum $L(r)=O(r^2)$ at $r\to 0$, no central singularity occurs. With $L(r)$…

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

The global visibility of a singularity as an end state of the gravitational collapse of a spherically symmetric pressureless cloud is investigated. We show the existence of a non-zero measured set of parameters: the total mass and the…

General Relativity and Quantum Cosmology · Physics 2022-11-15 Karim Mosani , Dipanjan Dey , Pankaj S. Joshi

A sufficiently massive collapsing star will end its life as a spacetime singularity. The nature of the Hawking radiation emitted during collapse depends critically on whether the star's boundary conditions are such as would lead to the…

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

We consider quantum theoretical effects of the sudden change of the boundary conditions which mimics the occurrence of naked singularities. For a simple demonstration, we study a massless scalar field in $(1 + 1)$-dimensional Minkowski…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Akihiro Ishibashi , Akio Hosoya

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

The end stage of a gravitational collapse process can generically result in a black hole or a naked singularity. Here we undertake a comparative analysis of the nature of tidal forces in these backgrounds. The effect of such forces is…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Akash Goel , Reevu Maity , Pratim Roy , Tapobrata Sarkar

We investigate the gravitational field of a static mass with quadrupole moment in empty space. It is shown that in general this configuration is characterized by the presence of curvature singularities without a surrounding event horizon.…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Hernando Quevedo

In this paper, the study of the gravitational collapse of cylindrically distributed two perfect fluid system has been carried out. It is assumed that the collapsing speeds of the two fluids are very large. We explore this condition by using…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Sharif , Zahid Ahmad

Self-accelerating solutions in massive gravity provide explicit, calculable examples that exhibit the general interplay between superluminality, the well-posedness of the Cauchy problem, and strong coupling. For three particular classes of…

High Energy Physics - Theory · Physics 2015-08-26 Pavel Motloch , Wayne Hu , Austin Joyce , Hayato Motohashi
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