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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 investigate here the gravitational collapse end states for a spherically symmetric perfect fluid with an equation of state $p=k\rho$. It is shown that given a regular initial data in terms of the density and pressure profiles at the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Rituparno Goswami , Pankaj S Joshi

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

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

Inspired by Raychaudhuri's work, and using the equation named after him as a basic ingredient, a new singularity theorem is proved. Open non-rotating everywhere expanding universes with non-vanishing spatial average of the matter variables…

General Relativity and Quantum Cosmology · Physics 2008-11-26 José M. M. Senovilla

The gravitational collapse of cylindrically distributed perfect fluid is studied. We assume the collapsing speed of fluid is very large and investigate such a situation by recently proposed high-speed approximation scheme. We show that if…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Ken-ichi Nakao , Yoshiyuki Morisawa

Spherically symmetric inhomogeneous dust collapse has been studied in higher dimensional space-time and the factors responsible for the appearance of a naked singularity are analyzed in the region close to the centre for the marginally…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Asit Banerjee , Ujjal Debnath , Subenoy Chakraborty

The dynamics of collapsing and expanding cylindrically symmetric gravitational and matter fields with lightlike wave-fronts is studied in General Relativity, using the Barrabes-Israel method. As an application of the general formulae…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Paulo R. C. T. Pereira , A. Z. Wang

Molecular cloud observations show that clouds have non-thermal velocity dispersions that scale with the cloud size as $\sigma\propto R^{1/2}$ at constant surface density, and for varying surface density scale with both the cloud`s size and…

Astrophysics of Galaxies · Physics 2016-06-15 Juan C. Ibáñez-Mejía , Mordecai-Mark Mac Low , Ralf S. Klessen , Christian Baczynski

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

Black holes are one of the most fascinating predictions of general relativity. They are the natural product of the complete gravitational collapse of matter and today we have a body of observational evidence supporting the existence of…

General Relativity and Quantum Cosmology · Physics 2023-07-26 Cosimo Bambi

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 study gravitational collapse of a spherical fluid in nonrelativistic general covariant theory of the Ho\v{r}ava-Lifshitz gravity with the projectability condition and an arbitrary coupling constant $\lambda$, where $|\lambda - 1|$…

High Energy Physics - Theory · Physics 2015-06-01 Jared Greenwald , Jonatan Lenells , V. H. Satheeshkumar , Anzhong Wang

Naked singularity occurs in the gravitational collapse of an inhomogeneous dust ball from an initial density profile which is physically reasonable. We show that explosive radiation is emitted during the formation process of the naked…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Tomohiro Harada , Hideo Iguchi , Ken-ichi Nakao

We model gravitational collapse leading to star formation in a wide range of isolated disk galaxies using a three-dimensional, smoothed particle hydrodynamics code. The model galaxies include a dark matter halo and a disk of stars and…

Astrophysics · Physics 2009-11-10 Yuexing Li , Mordecai-Mark Mac Low , Ralf S. Klessen

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

We examine the gravitational collapse and black hole formation of multiple non--spherical configurations constructed from Szekeres dust models with positive spatial curvature that smoothly match to a Schwarzschild exterior. These…

General Relativity and Quantum Cosmology · Physics 2018-05-22 Ismael Delgado Gaspar , Juan Carlos Hidalgo , Roberto A. Sussman , Israel Quiros

In this work, we explore the eternal collapsing phenomenon of a stellar system (e.g., a star) within the framework of $f(R)$ gravity and investigate some new aspects of the continued homogeneous gravitational collapse with perfect fluid…

General Relativity and Quantum Cosmology · Physics 2023-11-30 Annu Jaiswal , Rajesh Kumar , Sudhir Kumar Srivastava , Megandhren Govender

The gravitational collapse of spherical, barotropic perfect fluids is analyzed here. For the first time, the final state of these systems is studied without resorting to simplifying assumptions - such as self-similarity - using a new…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Roberto Giambo' , Fabio Giannoni , Giulio Magli , Paolo Piccione

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