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In this paper, we consider the gravitational collapse of generalized Vaidya space-time when the matter satisfies the equation of the state either $P=0$ or $P=-\alpha \rho$, where $0 < \alpha < 1$. We show that in the case when type I of…

General Relativity and Quantum Cosmology · Physics 2022-10-31 Vitalii Vertogradov

We investigate the occurrence and nature of naked singularity for the inhomogeneous gravitational collapse of Tolman-Bondi dust clouds.It is shown that the naked singularities form at the center of the collapsing cloud in a wide class of…

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

We obtain a general spherically symmetric solution of a null dust fluid in $n (\geq 4)$-dimensions in Gauss-Bonnet gravity. This solution is a generalization of the $n$-dimensional Vaidya-(anti)de Sitter solution in general relativity. For…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Hideki Maeda

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 construct a class of spherically symmetric collapse models in which a naked singularity may develop as the end state of collapse. The matter distribution considered has negative radial and tangential pressures, but the weak energy…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Rituparno Goswami , Pankaj S. Joshi , Cenalo Vaz , Louis Witten

We give a set of exact nonlinear closed--form solutions for the non-spherical collapse of pressure-less matter in Newtonian gravity, and indicate their possible cosmological applications. Keywords: Newtonian gravitation: free collapse,…

Astrophysics of Galaxies · Physics 2015-08-18 A. D. Chernin , A. S. Silbergleit

Recent developments on the final state of a gravitationally collapsing massive matter cloud are summarized and reviewed here. After a brief background on the problem, we point out how the black hole and naked singularity end states arise…

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

We comment here on the results in Ref [4] that showed naked singularities in dynamical gravitational collapse of inhomogeneous dust to be stable but non-generic. The definition of genericity used there is reconsidered. We point out that…

General Relativity and Quantum Cosmology · Physics 2012-07-17 Ravindra V. Saraykar , Pankaj S. Joshi

The phase space corresponding to a particular four-parameter family of initial data for the gravitational collapse of a spherically symmetric dust cloud is investigated. In a certain limit of the parameters, this family reproduces the case…

General Relativity and Quantum Cosmology · Physics 2015-03-20 Néstor Ortiz

The gravitational collapse of a high-density null charged matter fluid, satisfying the Hagedorn equation of state, is considered in the framework of the Vaidya geometry. The general solution of the gravitational field equations can be…

General Relativity and Quantum Cosmology · Physics 2009-11-10 T. Harko

We generalize the spherical collapse model for the formation of dark matter halos to apply in a universe with arbitrary positive cosmological constant. We calculate the critical condition for collapse of an overdense region and give exact…

Astrophysics · Physics 2016-11-03 Ewa L. Lokas , Y. Hoffman

We find the general solution of the Einstein equation for spherically symmetric collapse of Type II fluid (null strange quark fluid) in higher dimensions. It turns out that the nakedness and curvature strength of the shell focusing…

General Relativity and Quantum Cosmology · Physics 2016-08-31 S. G. Ghosh , Naresh Dadhich

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 2008-02-03 H. M. Antia

We prove a No-Go theorem for singularity resolution in gravitational collapse: within any analytic gravitational theory, including general relativity and all theories with polynomial actions, quantum corrections introduced solely as…

General Relativity and Quantum Cosmology · Physics 2026-04-02 Zhen-Xiao Zhang , Chen Lan , Yan-Gang Miao

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 singularity generating spacetimes both the out-going and in-going expansions of null geodesic congruences $\theta ^{+}$ and $\theta ^{-}$ should become increasingly negative without bound, inside the horizon. This behavior leads to…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Manasse R. Mbonye , Demosthenes Kazanas

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

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

We generalize the spherical collapse model for the formation of bound objects to apply in a Universe with arbitrary positive cosmological constant. We calculate the critical condition for collapse of an overdense region and give exact…

Astrophysics · Physics 2007-05-23 Ewa L. Lokas , Yehuda Hoffman

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