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In this article, we propose a physical condition to extend interior isotropic solutions to anisotropic domains by gravitational decoupling in the framework of the Minimal Geometric Deformation approach. In particular, it is found that by…

General Relativity and Quantum Cosmology · Physics 2020-03-24 Gabriel Abellán , Angel Rincon , Ernesto Fuenmayor , Ernesto Contreras

The consideration of a 1 + 3 covariant approach to cold dark matter universe with no shear cosmological dust model with irrotational flows is developed in the context of f (G) gravity theory in the present study. This approach reveals the…

General Relativity and Quantum Cosmology · Physics 2023-05-19 Albert Munyeshyaka , Joseph Ntahompagaze , Tom Mutabazi , Manasse. R Mbonye

The hydrodynamic description of probabilistic ballistic annihilation, for which no conservation laws hold, is an intricate problem with hard sphere-like dynamics for which no exact solution exists. We consequently focus on simplified…

Statistical Mechanics · Physics 2007-05-23 Francois Coppex , Michel Droz , Emmanuel Trizac

We report the findings of new exact analytical solutions to the cosmological fluid equations, namely for the case where the initial conditions are perturbatively close to a spherical top-hat profile. To do so we enable a fluid description…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-28 Cornelius Rampf

Gravitational collapse into a black hole has been extensively studied with classical sources. We develop a new formalism to simulate quantum fields forming a black hole. By choosing a convenient coherent state, this formalism taps into…

High Energy Physics - Theory · Physics 2022-03-09 Benjamin Berczi , Paul M. Saffin , Shuang-Yong Zhou

We investigate the gravitational collapse of a massive scalar field in a conformally flat, spherically symmetric spacetime within general relativity. The collapsing matter distribution is modeled using a minimally coupled homogeneous scalar…

General Relativity and Quantum Cosmology · Physics 2026-05-28 Mohamed Aarif A , Soumya Chakrabarti

We investigate the quality of space approximation of a class of stochastic integral equations of convolution type with Gaussian noise. Such equations arise, for example, when considering mild solutions of stochastic fractional order partial…

Numerical Analysis · Mathematics 2022-01-05 Erika Hausenblas , Mihály Kovács

The dynamical equations describing the evolution of a self-gravitating fluid of cold dark matter (CDM) can be written in the form of a Schrodinger equation coupled to a Poisson equation describing Newtonian gravity. It has recently been…

Astrophysics · Physics 2009-11-11 C. J. Short , P. Coles

In this paper, we consider well known Tolman V perfect fluid solution and extend it to its an anisotropic version using gravitational decoupling by minimal geometric deformation approach and analyze the behavior of new version of the…

General Relativity and Quantum Cosmology · Physics 2020-09-29 M. Zubair , Hina Azmat

A self-gravitating homogeneous ball of a fluid with pressure zero where the fluid particles are initially at rest collapses to a point in finite time. We prove that this gravitational collapse can be approximated arbitrarily closely by…

Mathematical Physics · Physics 2015-10-01 Gerhard Rein , Lukas Taegert

We derive a semi-geostrophic variational balance model for the three-dimensional Euler--Boussinesq equations on the non-traditional $f$-plane under the rigid lid approximation. The model is obtained by a small Rossby number expansion in the…

Analysis of PDEs · Mathematics 2021-07-28 Gözde Özden , Marcel Oliver

In this paper, we have studied gravitational collapse and expansion of non-static anisotropic fluid in $5D$ Einstein Gauss-Bonnet gravity. For this purpose, the field equations have been modeled and evaluated for the given source and…

General Relativity and Quantum Cosmology · Physics 2018-12-19 G. Abbas , M. Tahir

This work studies a simplified model of the gravitational instability of an initially homogeneous infinite medium, represented by $\TT^d$, based on the approximation that the mean fluid velocity is always proportional to the local…

Analysis of PDEs · Mathematics 2015-06-12 Yago Ascasibar , Rafael Granero-Belinchón , José Manuel Moreno

A particular class of space-time, with a tachyon field, \phi, and a barotropic fluid constituting the matter content, is considered herein as a model for gravitational collapse. For simplicity, the tachyon potential is assumed to be of…

General Relativity and Quantum Cosmology · Physics 2013-01-23 Yaser Tavakoli , João Marto , Amir Hadi Ziaie , Paulo Vargas Moniz

This article presents the study of a multi-species fluid characterised by a freeze-out or break-away of one or more species. Whereas single-fluid approximation suffices for modelling of the pre {\it freeze-out} period, multi-fluid…

General Relativity and Quantum Cosmology · Physics 2020-05-06 Bob Osano , Timothy Oreta

Possibilities emerging out of the dynamical evolutions of collapsing systems are addressed in this thesis through analytical investigations of the highly non-linear Einstein Field Equations. Studies of exact solutions and their properties,…

General Relativity and Quantum Cosmology · Physics 2017-09-07 Soumya Chakrabarti

Analysing two-dimensional shallow water equations with idealised bottom topographies have many applications in the atmospheric and oceanic sciences; however, restrictive flow pattern assumptions have been made to achieve explicit solutions.…

Fluid Dynamics · Physics 2023-05-01 Chang Liu , Antwan D. Clark

A new energy-based stochastic extension of the Schrodinger equation for which the wave function collapses after the passage of a finite amount of time is proposed. An exact closed-form solution to the dynamical equation, valid for all…

Quantum Physics · Physics 2009-11-11 Dorje C. Brody , Lane P. Hughston

We construct approximate solutions that will describe the last stage of cylindrically symmetric gravitational collapse of dust fluid. Just before the spacetime singularity formation, the speed of the dust fluid might be almost equal to the…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Ken-ichi Nakao , Yoshiyuki Morisawa

Critical gravitational collapse offers a unique window into regimes of arbitrarily high curvature, culminating in a naked singularity arising from smooth initial data -- thus providing a dynamical counterexample to weak cosmic censorship.…

General Relativity and Quantum Cosmology · Physics 2026-05-18 Marija Tomašević , Chih-Hung Wu