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Related papers: Null Fluid collapse in Rastall theory of gravity

200 papers

It has been suggested that a naked singularity may be a good candidate for a strong gravitational wave burster. The naked singularity occurs in the generic collapse of an inhomogeneous dust ball. We study odd-parity mode of gravitational…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Hideo Iguchi , Tomohiro Harada , Ken-ichi Nakao

We study the spherically symmetric collapse of a cloud of dust in VCDM, a class of gravitational theories with two local physical degrees of freedom. We find that the collapse corresponds to a particular foliation of the Oppenheimer-Snyder…

General Relativity and Quantum Cosmology · Physics 2023-03-22 Antonio De Felice , Kei-ichi Maeda , Shinji Mukohyama , Masroor C. Pookkillath

In this work we study the dynamics of gravitational collapse of a homogeneous dust sphere in a model exhibiting a linear non-minimal coupling between matter and curvature. The evolution of the scale factor and the matter density is obtained…

General Relativity and Quantum Cosmology · Physics 2012-12-12 J. Páramos , C. Bastos

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

Here we constructed a charged gravastar model formed by an interior de Sitter spacetime, a charged dynamical infinitely thin shell with an equation of state and an exterior de Sitter-Reissner-Nordstr\"om spacetime. We find that the presence…

General Relativity and Quantum Cosmology · Physics 2013-09-10 C. F. C. Brandt , R. Chan , M. F. A. da Silva , P. Rocha

We examine the question as to whether the Palatini f(R) gravity theories permit space-times in which the causality is violated. We show that every perfect-fluid G\"{o}del-type solution of Palatini f(R) gravity with density $\rho$ and…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-30 J. Santos , M. J. Reboucas , T. B. R. F. Oliveira

Naked singularities form during the gravitational collapse of inhomogeneous matter clouds. The final nature of the singularity depends on the initial conditions of the matter properties and types of matter profiles. These naked…

General Relativity and Quantum Cosmology · Physics 2022-06-01 Siddharth Madan , Parth Bambhaniya

New physics beyond General Relativity impacts black-hole spacetimes. The effects of new physics can be investigated in a largely theory-agnostic way by following the principled-parameterized approach. In this approach, a classical…

General Relativity and Quantum Cosmology · Physics 2025-03-06 Héloïse Delaporte , Astrid Eichhorn

Interested in the collapse of a radiating star, we study the temporal evolution of a fluid with heat flux and bulk viscosity, including anisotropic pressure. As a starting point, we adopt an initial configuration that satisfies the…

General Relativity and Quantum Cosmology · Physics 2018-11-27 L. S. M. Veneroni , M. F. A. da Silva

We consider spherically symmetric spacetimes sourced by a fluid with pressure anisotropy in the radial direction. We use gauge-invariant perturbation theory to study the stability of this class of spacetimes under axial perturbations. We…

General Relativity and Quantum Cosmology · Physics 2014-07-23 Bhavesh Khamesra , V Suneeta

In this paper, we investigate the geodesic motion of massive and massless test particles in the vicinity of a black hole space-time surrounded by perfect fluid (quintessence, dust, radiation, cosmological constant and phantom) in Rastall…

General Relativity and Quantum Cosmology · Physics 2021-02-15 Saheb Soroushfar , Maryam Afrooz

We study the formation of a black hole and its subsequent evaporation in a model employing a minisuperspace approach to loop quantum gravity. In previous work the static solution was obtained and shown to be singularity-free. Here, we…

General Relativity and Quantum Cosmology · Physics 2010-04-21 Sabine Hossenfelder , Leonardo Modesto , Isabeau Prémont-Schwarz

We analyze spherical dust collapse with non-vanishing radial pressure, $\Pi$, and vanishing tangential stresses. Considering a barotropic equation of state, $\Pi=\gamma\rho$, we obtain an analytical solution in closed form---which is exact…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Sergio M. C. V. Goncalves , Sanjay Jhingan

A naked singularity occurs in the generic collapse of an inhomogeneous dust ball. We study the even-parity mode of gravitational waves from a naked singularity of the Lema\^{\i}tre-Tolman-Bondi spacetime. The wave equations for…

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

We study the behavior of a self-gravitating perfect relativistic fluid satisfying the Einstein-Euler system in the presence of a weak null terminal spacetime singularity. This type of singularities is expected in the interior of generic…

General Relativity and Quantum Cosmology · Physics 2026-05-05 Yuefeng Song

We study here the unhindered gravitational collapse of spatially homogeneous (SH) scalar fields $\phi$ with a potential $V_{s}(\phi)$, as well as vector fields $\tilde{A}$ with a potential $V_{v}(B)$ where $B=g(\tilde{A},\tilde{A})$ and $g$…

General Relativity and Quantum Cosmology · Physics 2023-01-13 Karim Mosani , Koushiki , Pankaj S. Joshi , Jay Verma Trivedi , Tapobroto Bhanja

This paper is devoted to study the charged perfect fluid cylindrical gravitational collapse. For this purpose, we find a new analytical solution of the field equations for non-static cylindrically symmetric spacetime. We discuss physical…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Muhammad Sharif , Ghulam Abbas

Using the conventional gravastar model, that is, an object constituted by two components where one of them is a massive infinitely thin shell and the other one is a de Sitter interior spacetime, we physically interpret a solution…

General Relativity and Quantum Cosmology · Physics 2012-10-30 R. Chan , M. F. A. da Silva , Jaime F. Villas da Rocha

We study the problem of the gravitational collapse of an object as seen by an external observer. We assume that the resultant spacetime is a match of an external Vaidya spacetime with an interior Friedmann-Lema\^itre-Robertson-Walker (FRLW)…

General Relativity and Quantum Cosmology · Physics 2023-12-27 Eduardo Bittencourt , Alan G. Cesar , Jonas P. Pereira

This paper is devoted to analytical solutions for the base flow and temporal stability of a liquid film driven by gravity over an inclined plane when the fluid rheology is given by the Carreau-Yasuda model, a general description that…

Fluid Dynamics · Physics 2020-07-10 Bruno Pelisson Chimetta , Erick de Moraes Franklin