English
Related papers

Related papers: Non-radial null geodesics in spherical dust collap…

200 papers

We investigate the formation of a locally naked singularity in the collapse of radiation shells in an expanding Vaidya-deSitter background. This is achieved by considering the behaviour of non-spacelike and radial geodesics originating at…

General Relativity and Quantum Cosmology · Physics 2015-06-25 S. M. Wagh , S. D. Maharaj

We investigate here the causal structure of spacetime in the vicinity of a spacetime singularity. The particle and energy emission from such ultra-dense regions forming in gravitational collapse of a massive matter cloud is governed by the…

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

We describe a simple method of determining whether the singularity that forms in the spherically symmetric collapse of inhomogeneous dust is naked or covered. This derivation considerably simplifies the analysis given in the earlier…

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

We present an algorithm for the construction of conformal coordinates in the interior of a spherically symmetric, collapsing matter cloud in general relativity. This algorithm is based on the numerical integration of the radial null…

General Relativity and Quantum Cosmology · Physics 2014-06-17 Néstor Ortiz , Olivier Sarbach

We study the formation of central naked singularities in spherical dust collapse with a cosmological constant. We find that the central curvature singularity is locally naked, Tipler strong, and generic, in the sense that it forms from a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Sergio M. C. V. Goncalves

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 investigate the occurrence and nature of a naked singularity in the gravitational collapse of an inhomogeneous dust cloud described by higher dimensional Tolman-Bondi space-time. The naked singularities are found to be gravitationally…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ujjal Debnath , Subenoy Chakraborty

We examine the role of the initial density and velocity distribution in the gravitational collapse of a spherical inhomogeneous dust cloud. Such a collapse is described by the Tolman-Bondi metric which has two free functions: the…

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

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

The gravitational collapse of an infinite cylindrical thin shell of generic matter in an otherwise empty spacetime is considered. We show that geometries admitting two hypersurface orthogonal Killing vectors cannot contain trapped surfaces…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sergio M. C. V. Goncalves

We consider here the effects of a non-vanishing cosmological term on the final fate of a spherical inhomogeneous collapsing dust cloud. It is shown that depending on the nature of the initial data from which the collapse evolves, and for a…

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

Using the general formalism for spherical gravitational collapse developed in [1], we investigate here the final fate of a spherical distribution of a matter cloud, where radial pressures vanish but tangential pressures are non-zero. Within…

General Relativity and Quantum Cosmology · Physics 2011-05-09 Daniele Malafarina , Pankaj S. Joshi

We study the occurrence, visibility, and curvature strength of singularities in dust-containing Szekeres spacetimes (which possess no Killing vectors) with a positive cosmological constant. We find that such singularities can be locally…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sergio M. C. V. Goncalves

We investigate the end state of the gravitational collapse of an inhomogeneous dust cloud in higher dimensional space-time. The naked singularities are shown to be developing as the final outcome of non-marginally bound collapse. The naked…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Ujjal Debnath , Subenoy Chakraborty

Spherical dust collapse generally forms a shell focusing naked singularity at the symmetric center. This naked singularity is massless. Further the Newtonian gravitational potential and speed of the dust fluid elements are everywhere much…

General Relativity and Quantum Cosmology · Physics 2009-10-31 K. Nakao , H. Iguchi , T. Harada

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

It has been claimed that the Lemaitre-Tolman-Bondi-de Sitter solution always admits future-pointing radial time-like geodesics emerging from the shell-focussing singularity, regardless of the nature of the (regular) initial data. This is…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Brien C. Nolan , Filipe C. Mena , Sergio M. C. V. Goncalves

In this paper we study the quasi-spherical gravitational collapse of (n+2) dimensional Szekeres space-time. The nature of the central shell focusing singularity so formed is analyzed by studying both the radial null and time-like geodesic…

Mathematical Physics · Physics 2009-11-10 Ujjal Debnath , Subenoy Chakraborty

We investigate the occurrence and nature of a naked singularity in the gravitational collapse of an inhomogeneous dust cloud described by a self-similar higher dimensional Tolman-Bondi space-time. Bound, marginally bound and unbound…

General Relativity and Quantum Cosmology · Physics 2009-11-07 S. G. Ghosh , A. Banerjee