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We show that a general solution of the Einstein equations that describes approach to an inhomogeneous and anisotropic sudden spacetime singularity does not experience geodesic incompleteness. This generalises the result established for…

General Relativity and Quantum Cosmology · Physics 2013-09-11 John D. Barrow , S. Cotsakis

An algorithm based on the choice of a single monotone function (subject to boundary conditions) is presented which generates all regular static spherically symmetric perfect fluid solutions of Einstein's equations. For physically relevant…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Kayll Lake

In this paper, we extend the Finch-Skea isotropic ansatz representing a self-gravitating interior to two anisotropic spherical solutions within the context of Rastall gravity. For this purpose, we use a newly developed technique, named as…

General Relativity and Quantum Cosmology · Physics 2024-10-03 M. Sharif , M. Sallah

A new solution of Einstein's vacuum field equations is discovered which appears as a generalization of the well-known Ozsvath-Schucking solution and explains its source of curvature which has otherwise remained hidden. Curiously, the new…

General Relativity and Quantum Cosmology · Physics 2015-09-22 Ram Gopal Vishwakarma

The paper considers a set of equations describing the static isotropic gravity field of a macroscopic body within the framework of the theory of gravity with a constraint. A general approximate solution of these equations is obtained. The…

General Relativity and Quantum Cosmology · Physics 2024-02-08 Alexander P. Sobolev , Aleksey Sobolev

The popularity of the Finch-Skea ansatz to describe relativistic stellar model have encouraged us to study the analytic solutions of the Einstein field equation. We have presented a class of exact solutions to the field equations after…

General Relativity and Quantum Cosmology · Physics 2021-07-14 Shyam Das , Koushik Chakraborty , Lipi Baskey , Saibal Ray

We investigate static spherically symmetric solutions within the framework of the local limit of nonlocal gravity. This theory departs from Einstein's general relativity (GR) through the introduction of a scalar gravitational susceptibility…

General Relativity and Quantum Cosmology · Physics 2025-09-25 Yahya Mohammadi , Javad Tabatabaei , Shant Baghram , Bahram Mashhoon

The Vlasov-Einstein system describes the evolution of an ensemble of particles (such as stars in a galaxy, galaxies in a galaxy cluster etc.) interacting only by the gravitational field which they create collectively and which obeys…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Gerhard Rein

This article is the second of two in which we develop a geometric framework for analysing silent and anisotropic big bang singularities. In the present article, we record geometric conclusions obtained by combining the geometric framework…

General Relativity and Quantum Cosmology · Physics 2026-03-03 Hans Ringström

The Kerr solution for empty space-time is presented in an ellipsoidally symmetric coordinate system and it is used to produce generalised ellipsoidal metrics appropriate for the generation of rotating interior solutions of Einstein's…

General Relativity and Quantum Cosmology · Physics 2015-05-27 R. J. Wiltshire

Based upon the intrinsic symmetries approach to inhomogeneous cosmologies, we propose an exact solution to Einstein's field equations where the spatial sections are flat and the source is a non-perfect fluid such that the dissipative terms…

General Relativity and Quantum Cosmology · Physics 2021-03-11 E. Bittencourt , L. G. Gomes , G. B. Santos

We study a static spherically symmetric problem with a black hole and radially directed geodesic flows of dark matter. The obtained solutions have the following properties. At large distances, the gravitational field produces constant…

General Relativity and Quantum Cosmology · Physics 2021-02-11 Igor Nikitin

In this paper, we investigate the anisotropic interior spherically symmetric solutions by utilizing the extended gravitational decoupling method in the background of $f(G,T)$ gravity, where $G$ and $T$ signify the Gauss-Bonnet term and…

General Relativity and Quantum Cosmology · Physics 2024-06-05 M. Sharif , K. Hassan

On a smooth metric measure spacetime $(M,g,e^{-f} dvol_g)$, we define a weighted Einstein tensor. It is given in terms of the Bakry-\'Emery Ricci tensor as a tensor which is symmetric, divergence-free, concomitant of the metric and the…

Differential Geometry · Mathematics 2022-06-29 Miguel Brozos-Vázquez , Diego Mojón-Álvarez

In this work we investigate analytic static and spherically symmetric solutions of a generalized theory of gravity in the Einstein-Cartan formalism. The main goal consists in analyzing the behavior of the solutions under the influence of a…

General Relativity and Quantum Cosmology · Physics 2018-08-15 F. A. Silveira , R. F. Sobreiro , A. A. Tomaz

In this work, we have obtained exact solutions of Einstein equations for static and axially symmetric magnetized matter, specifically in plane-symmetric and almost-plane symmetric cases. Although these solutions impose constraints on the…

General Relativity and Quantum Cosmology · Physics 2018-04-05 Ernesto Contreras , Pedro Bargueno , Gretel Quintero , Aurora Perez-Martinez , Diana Alvear

We consider numerically dynamics of a flat anisotropic Universe in Einstein-Gauss-Bonnet gravity with positive $\Lambda$ in dimensionalities 5+1 and 6+1. We identify three possible outcomes of the evolution, one singular and two…

General Relativity and Quantum Cosmology · Physics 2019-07-25 Dmitry Chirkov , Alexey Toporensky

The purpose of this paper is to obtain exact solutions for charged anisotropic spherically symmetric matter configuration. For this purpose, we consider known solution for isotropic spherical system in the presence of electromagnetic field…

General Relativity and Quantum Cosmology · Physics 2018-07-04 M. Sharif , Sobia Sadiq

Extensions of Einstein gravity with quadratic curvature terms in the action arise in most effective theories of quantised gravity, including string theory. This article explores the set of static, spherically symmetric and asymptotically…

High Energy Physics - Theory · Physics 2015-12-22 H. Lü , A. Perkins , C. N. Pope , K. S. Stelle

We investigate the vacuum and charged spherically symmetric static solutions of the Einstein equations on cosmological background. The background metric is not flat, but curved, with constant - curvature spatial sections. Both vacuum and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. N. Tentyukov