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We consider here the gravitational collapse of a spherically symmetric inhomogeneous dust cloud described by the Tolman-Bondi models. By studying a general class of these models, we find that the end state of the collapse is either a black…

General Relativity and Quantum Cosmology · Physics 2009-10-22 P. S. Joshi , T. P. Singh

We study here the behaviour of non-spacelike geodesics in dust collapse models in order to understand the casual structure of the spacetime. The geodesic families coming out, when the singularity is naked, corresponding to different initial…

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

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

The visibility of the shell-focusing singularity in Szekeres space-time - which represents quasi-spherical dust collapse - has been studied on numerous occasions in the context of the cosmic censorship conjecture. The various results…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Brien C. Nolan , Ujjal Debnath

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

While studying the continual gravitational collapse of a massive matter cloud in general relativity towards examining collapse final states, an important issue is that of whether shell-crossing singularities can develop as the collapse…

General Relativity and Quantum Cosmology · Physics 2013-04-30 Pankaj S. Joshi , Ravindra V. Saraykar

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

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

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 consider spherically symmetric spacetimes with matter whose timelike flow is assumed to be shear-free. A number of results on the formation and visibility of spacetime singularities is proven, with the main one being that shear-free…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Sergio M. C. V. Goncalves

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

Various types of inhomogeneous collapse models in general relativity (GR) lead to the formation of spacetime singularities either visible or hidden by a spacetime horizon. Our aim in the present work is to search for nonsingular models in…

General Relativity and Quantum Cosmology · Physics 2025-07-04 Akbar Jahan , Halime Miraghaei , Shayesteh Ghaffari , Amir Hadi Ziaie

We consider the evaporation of the (shell focusing) naked singularity formed during the self-similar collapse of a marginally bound inhomogeneous dust cloud, in the geometric optics approximation. We show that, neglecting the back reaction…

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

We consider gravitational collapse in the recently proposed 4D limit of Einstein-Gauss-Bonnet gravity. We show that for collapse of a sphere made of homogeneous dust the process is qualitatively similar to the case of pure Einstein's…

General Relativity and Quantum Cosmology · Physics 2020-06-04 Daniele Malafarina , Bobir Toshmatov , Naresh Dadhich

We consider general relativistic homogeneous gravitational collapses for dust and radiation. We show that replacing the density profile with an effective density justified by some quantum gravity framework leads to the avoidance of the…

General Relativity and Quantum Cosmology · Physics 2013-08-07 Cosimo Bambi , Daniele Malafarina , Leonardo Modesto

We study the gravitational collapse in ($n+2$)-D quasi-spherical Szekeres space-time (which possess no killing vectors) with dust as the matter distribution. Instead of choosing the radial coordinate `$r$' as the initial value for the scale…

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

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

We investigate here how the shearing effects present within a collapsing matter cloud influence the outcome of gravitational collapse in terms of formation of either a black hole or a naked singularity as the final end state. For collapse…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Pankaj S. Joshi , Rituparno Goswami , Naresh Dadhich

In this article, we present a gravitational collapse null dust solution of the Einstein field equations. The spacetime is regular everywhere except on the symmetry axis where it possesses a naked curvature singularity, and admits one…

General Relativity and Quantum Cosmology · Physics 2017-06-14 Faizuddin Ahmed

We study the spherically symmetric collapse of a cloud of dust in VCDM, a class of gravitational theories with two local physical degrees of freedom. We find that the collapse corresponds to a particular foliation of the Oppenheimer-Snyder…

General Relativity and Quantum Cosmology · Physics 2023-03-22 Antonio De Felice , Kei-ichi Maeda , Shinji Mukohyama , Masroor C. Pookkillath