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Related papers: Shell-crossings in Gravitational Collapse

200 papers

In order to develop a complete theory of star formation, one essentially needs to know two things: what collapses, and how long it takes. This is the second paper in a series, where we query how long a parcel of gas takes to collapse and…

Astrophysics of Galaxies · Physics 2024-06-13 David C. Collins , Dan K. Le , Luz L. Jimenez Vela

Generalizing earlier results of Joshi and Dwivedi (Commun. Math. Phys. 146, 333 (1992); Lett. Math. Phys. 27, 235 (1993)), we analyze here the spherically symmetric gravitational collapse of a matter cloud with a general form of matter for…

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

We analyse here the gravitational collapse of directed null radiation in a background with a constant potential such as one produced by a star system like galaxy in which the collapsing object is immersed. Both naked singularities and black…

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

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

A system of two gravitating bodies floating around a restricted region of strong gravitational field is investigated. We consider two concentric spherically symmetric timelike shells spatially constrained by a perfectly reflecting inner and…

General Relativity and Quantum Cosmology · Physics 2023-12-22 Takafumi Kokubu

In this dissertation we study two well known gravitational scenarios in which singularities may appear; the final state of gravitational collapse and the late time evolution of the universe. In the first scenario, we study a spherically…

General Relativity and Quantum Cosmology · Physics 2014-05-22 Yaser Tavakoli

This article reviews classical and quantum aspects of critical phenomena in gravitational collapse. We pay special attention to the origin of the scaling law for black hole mass, and to phase transitions in which black hole formation turns…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Patrick R Brady , Mike J Cai

During gravitational collapse of dust in spherical symmetry, matter particles may collide forming shell crossing surfaces (SCS) on which the Einstein equations become indeterministic. We show that there is a unique evolution beyond SCS such…

General Relativity and Quantum Cosmology · Physics 2026-01-23 Viqar Husain , Hassan Mehmood

We investigate the occurrence and nature of naked singularities in the gravitational collapse of an adiabatic perfect fluid in self-similar higher dimensional space-times. It is shown that strong curvature naked singularities could occur if…

General Relativity and Quantum Cosmology · Physics 2009-11-10 S. G. Ghosh , D. W. Deshkar

We study the spherically symmetric collapse of a perfect fluid using area-radial coordinates. We show that analytic mass functions describe a static regular centre in these coordinates. In this case, a central singularity can not be…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Hideo Iguchi , Tomohiro Harada , Filipe C Mena

We examine here in what way the pressures affect the final fate of a continual gravitational collapse. It is shown that the presence of a non-vanishing pressure gradient in the collapsing cloud determines directly the epoch of formation of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Rituparno Goswami , Pankaj S Joshi

We study the backreaction of quantum fields induced through the vacuum polarization and the conformal anomaly on the collapse of a thin shell of dust. It is shown that the final fate of the collapse process depends on the physical…

High Energy Physics - Theory · Physics 2023-07-19 Moslem Shafiee , Yousef Bahrampour

Asymptotic safety (an ultraviolet fixed point with finite-dimensional critical surface) offers the possibility that a predictive theory of quantum gravity can be obtained from the quantization of classical general relativity. However, it is…

General Relativity and Quantum Cosmology · Physics 2011-06-27 Roberto Casadio , Stephen D. H. Hsu , Behrouz Mirza

In this paper, we explore a collapsing scenario in the background of energy-momentum squared gravity (EMSG). EMSG claims to have terms that originate from the quantum gravity effects mimicking loop quantum gravity. As a result, the…

General Relativity and Quantum Cosmology · Physics 2024-02-14 Prabir Rudra

When the gas of a magnetized filamentary cloud obeys a polytropic equation of state, gravitational collapse of the cloud is studied using a simplified model. We concentrate on the radial distribution and restrict ourselves to the purely…

Astrophysics · Physics 2009-11-10 Mohsen Shadmehri

In the present work we study collapse process of a homogeneous and isotropic fluid in Brans-Dicke ({BD}) theory with non-vanishing spacetime torsion. In this theory, torsion can be generated by the {BD} scalar field as well as the intrinsic…

General Relativity and Quantum Cosmology · Physics 2024-02-14 A. H. Ziaie , H. Shabani , H. Moradpour

In general relativity, gravitational collapse of matter fields ends with the formation of a spacetime singularity, where the matter density becomes infinite and standard physics breaks down. According to the weak cosmic censorship…

General Relativity and Quantum Cosmology · Physics 2014-08-05 Lingyao Kong , Daniele Malafarina , Cosimo Bambi

The thermal and chemical evolution of gravitationally collapsing protostellar clouds is investigated, focusing attention on their dependence on metallicity. Calculations are carried out for a range of metallicities spanning the local…

Astrophysics · Physics 2009-10-31 Kazuyuki Omukai

In this paper the currently held view that the endpoint of gravitational collapse is a singularity is refuted. A quantum mechanical calculation is done showing that spin 0 and spin 1/2 particles inside a black hole's schwarzschild radius…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Julian B. Wilson

Extending previous work on the formation and the evaporation of black holes in conformal gravity, in the present paper we study the gravitational collapse of a spherically symmetric and electrically charged thin shell of radiation. The…

General Relativity and Quantum Cosmology · Physics 2018-09-03 Cosimo Bambi , Leonardo Modesto , Shiladitya Porey , Leslaw Rachwal