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Related papers: On the Shape of the First Collapsed Objects

200 papers

We numerically study the dynamics of an imploding hollow cylinder composed of dust. Since there is no cylindrical black hole in 4-dimensional spacetime with physically reasonable energy conditions, a collapsed dust cylinder involves a naked…

General Relativity and Quantum Cosmology · Physics 2009-11-19 Ken-ichi Nakao , Tomohiro Harada , Yasunari Kurita , Yoshiyuki Morisawa

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

To understand the formation of stars from clouds of molecular gas, one essentially needs to know two things: What gas collapses, and how long it takes to do so. We address these questions by embedding pseudo-Lagrangian tracer particles in…

Astrophysics of Galaxies · Physics 2022-10-12 David C. Collins , Dan K. Le , Luz L. Jimenez Vela

Gravitational collapse of the cylindrical elongated cloud is studied by numerical magnetohydrodynamical simulations. In the infinitely long cloud in hydrostatic configuration, small perturbations grow by the gravitational instability. The…

Astrophysics · Physics 2009-10-22 Kohji Tomisaka

This paper considers the quantum collapse of infinitesimally thin dust shells in 2+1 gravity. In 2+1 gravity a shell is no longer a sphere but a ring of matter. The classical equation of motion has been considered by Peleg and Steif and…

General Relativity and Quantum Cosmology · Physics 2008-11-26 L. Ortíz , M. P. Ryan

We describe the results of a simulation of collisionless cold dark matter in a LambdaCDM universe to examine the properties of objects collapsing at high redshift (z=10). We analyze the halos that form at these early times in this…

Astrophysics · Physics 2009-10-31 Hannah Jang-Condell , Lars Hernquist

The distributions of dark matter and baryons in the Universe are known to be very different: the dark matter resides in extended halos, while a significant fraction of the baryons have radiated away much of their initial energy and fallen…

High Energy Physics - Phenomenology · Physics 2018-02-14 Matthew R. Buckley , Anthony DiFranzo

We study how the presence of an area gap, different than zero, affects the gravitational collapse of a dust ball. The implementation of such discreteness is achieved through the framework of polymer quantization, a scheme inspired by loop…

General Relativity and Quantum Cosmology · Physics 2025-05-13 L. Boldorini , G. Montani

Generalizing earlier results on the initial data and the final fate of dust collapse, we study here the relevance of the initial state of a spherically symmetric matter cloud towards determining its end state in the course of a continuing…

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

The processes that led to the formation of the planetary bodies in the Solar System are still not fully understood. Using the results obtained with the comprehensive suite of instruments on-board ESA's Rosetta mission, we present evidence…

I present an analytic model for the early post-collapse evolution of a spherical density peak on the coherence scale of the initial fluctuations in a universe filled with collisionless and pressure-free "dust". On a time-scale which is…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-28 Simon D. M. White

A massive star undergoes a continual gravitational collapse when the pressures inside the collapsing star become insufficient to balance the pull of gravity. The Physics of gravitational collapse of stars is well studied. Using general…

General Relativity and Quantum Cosmology · Physics 2019-07-31 Dipanjan Dey , Pankaj S. Joshi

Collapse of the rotating spheroid is approximated by a system of ordinary differential equations describing its dynamics. The gravitational potential is approximated by the one of the iniform Maclaurin spheroid. Developement of…

Astrophysics · Physics 2016-08-30 G. S. Bisnovatyi-Kogan

The first dark matter halos form by direct collapse from peaks in the matter density field, and evidence from numerical simulations and other analyses suggests that the dense inner regions of these objects largely persist today. These halos…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-24 M. Sten Delos , Margie Bruff , Adrienne L. Erickcek

The caustic skeleton model is a mathematically rigorous framework for studying the formation history of the emerging cosmic web from the caustics in the underlying dark matter flow. In a series of two papers, we use constrained N-body…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-06 Benjamin Hertzsch , Job Feldbrugge , Maé Rodriguez , Rien van de Weygaert

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

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 examine how coupled dark matter and dark energy modify the development of Zel'dovich pancakes. We study how the various effects of these theories, such as a fifth force in the dark sector and a modified particle Hubble drag, produce…

Astrophysics · Physics 2008-02-14 P. M. Sutter , P. M. Ricker

We explore the end state of gravitational collapse under quantum gravity effects and propose that Planck Star Remnants (PSR), formed via nonsingular bounces, could serve as viable dark matter candidates. Within the framework of Loop Quantum…

General Relativity and Quantum Cosmology · Physics 2026-03-17 Oem Trivedi , Abraham Loeb

To constrain the nature of the very first stars, we investigate the collapse and fragmentation of primordial, metal-free gas clouds. We explore the physics of primordial star formation by means of three-dimensional simulations of the dark…

Astrophysics · Physics 2009-11-06 Volker Bromm , Paolo S. Coppi , Richard B. Larson