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Related papers: On "hard stars" in general relativity

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We consider stability of non-rotating gaseous stars modeled by the Euler-Poisson system. Under general assumptions on the equation of states, we proved a turning point principle (TPP) that the stability of the stars is entirely determined…

Analysis of PDEs · Mathematics 2021-02-02 Zhiwu Lin , Chongchun Zeng

We present for the first time solutions in the gauged $U(1)\times U(1)$ model of Witten describing vortons -- spinning flux loops stabilized against contraction by the centrifugal force. Vortons were heuristically described many years ago,…

High Energy Physics - Theory · Physics 2013-10-29 Julien Garaud , Eugen Radu , Mikhail S. Volkov

We discuss numerical solutions of Einstein's field equation describing static, spherically symmetric conglomerations of a photon gas. These equations imply a back reaction of the metric on the energy density of the photon gas according to…

General Relativity and Quantum Cosmology · Physics 2015-06-25 H. -J. Schmidt , F. Homann

We study the long time behavior of isentropic compressible Euler equations with linear damping driven by a white-in-time noise, on a one-dimensional torus. We prove the existence of a statistically stationary solution in the class of weak…

Analysis of PDEs · Mathematics 2025-11-03 Jeffrey Kuan , Krutika Tawri , Konstantina Trivisa

We study the properties of compact stars in the Randall-Sundrum II type braneworld model. To this end, we solve the braneworld generalization of the stellar structure equations for a static fluid distribution with spherical symmetry…

General Relativity and Quantum Cosmology · Physics 2017-09-01 Germán Lugones , José D. V. Arbañil

In this paper we study the even part of the linear stability of the Schwarzschild spacetime as a continuation of [22]. By taking the harmonic gauge, we prove that the energy decays at a rate $\tau^{-2+}$ for the solution of the linearized…

General Relativity and Quantum Cosmology · Physics 2019-09-17 Pei-Ken Hung

We consider compact boson stars that arise for a V-shaped scalar field potential. They represent a one parameter family of solutions of the scaled Einstein-signum-Gordon equations. We analyze the physical properties of these solutions and…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Betti Hartmann , Burkhard Kleihaus , Jutta Kunz , Isabell Schaffer

We obtain an approximate global stationary and axisymmetric solution of Einstein's equations which can be thought as a simple two layers star model: a self-gravitating ball built up by two layers of perfect fluid having different linear…

General Relativity and Quantum Cosmology · Physics 2018-06-12 Alfred Molina , Eduardo Ruiz

We consider the equations for the coefficients of stationary rotating axisymmetric metrics governed by the Einstein-Euler equations, that is, the Einstein equations together with the energy-momentum tensor of a barotropic perfect fluid.…

Analysis of PDEs · Mathematics 2020-09-30 Tetu Makino

A pure nucleonic equation of state (EoS) for beta equilibrated charge neutral neutron star (NS) matter is determined using density dependent effective NN interaction. This EoS is found to satisfy both the constraints from the observed…

Nuclear Theory · Physics 2011-05-11 Partha Roy Chowdhury

We consider plane-symmetric spacetimes satisfying Einstein's field equations with positive cosmological constant, when the matter is a fluid whose pressure is equal to its mass-energy density (i.e. a so-called stiff fluid). We study the…

General Relativity and Quantum Cosmology · Physics 2012-05-01 Philippe G. LeFloch , Sophonie B. Tchapnda

This paper deals with isothermal Euler-Poisson system which is used to model collapse of self-gravitating Newtonian star. Density dependent viscosity term is added on the right-hand side of momentum equation and it has been proved that…

Analysis of PDEs · Mathematics 2025-08-19 Marko Nedeljkov , Sanja Ružičić

In the present paper we have constructed a new relativistic anisotropic compact star model having a spherically symmetric metric of embedding class one. Here we have assumed an arbitrary form of metric function and solved the Einstein…

General Relativity and Quantum Cosmology · Physics 2017-07-26 Piyali Bhar , Ksh. Newton Singh , Tuhina Manna

In this article, an exact solution of Einstein's field equations for spherically symmetric anisotropic matter distributions in isotropic coordinates is obtained. For this, the solution has been obtained by using a generalized physically…

General Relativity and Quantum Cosmology · Physics 2025-08-25 B S Ratanpal , Bhavesh Suthar

We consider perfect fluid bodies (stars) in general relativity, characterized by particle number density and entropy per particle. A star is said to be in dynamic equilibrium if it is a stationary, axisymmetric solution to the…

General Relativity and Quantum Cosmology · Physics 2014-01-22 Stephen R. Green , Joshua S. Schiffrin , Robert M. Wald

We study the solution space of general relativistic, axisymmetric, equilibria of differentially rotating neutron stars with realistic, nuclear equations of state. We find that different types of stars, which were identified by earlier works…

High Energy Astrophysical Phenomena · Physics 2019-05-08 Pedro Espino , Vasileios Paschalidis

We provide new exact solutions to the Einstein-Maxwell system of equations for matter configurations with anisotropy and charge. The spacetime is static and spherically symmetric. A quadratic equation of state is utilised for the matter…

General Relativity and Quantum Cosmology · Physics 2016-01-06 Sifiso A. Ngubelanga , Sunil D. Maharaj , Subharthi Ray

By applying Noether symmetry methods, analytic solutions are obtained for a generalized Einstein-scalar-Gauss-Bonnet model with a $\xi(\phi)f(G)$ component. Variation with respect to the metric, supplemented by small perturbations, produces…

General Relativity and Quantum Cosmology · Physics 2025-12-15 Olga Razina , Dauren Rakhatov , Pyotr Tsyba , Emilio Elizalde

For the non-rotating gaseous stars modeled by the compressible Euler-Poisson system with general pressure law, Lin and Zeng [18] proved a turning point principle, which gives the sharp linear stability/instability criteria for the…

Analysis of PDEs · Mathematics 2023-08-21 Zhiwu Lin , Yucong Wang , Hao Zhu

We construct a one-parameter family of static and spherically symmetric solutions to the Einstein-Vlasov system bifurcating from the Schwarzschild spacetime. The constructed solutions have the property that the spatial support of the matter…

Analysis of PDEs · Mathematics 2020-01-24 Fatima Ezzahra Jabiri
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