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Related papers: Anisotropic Stars: Exact Solutions and Stability

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Quasi-local variables, i.e. quantities whose values can be derived from physics accessible within an arbitrarily small neighborhood of a spacetime point, are used to construct the equation of state (EoS) for the anisotropic fluid in the…

General Relativity and Quantum Cosmology · Physics 2011-01-20 Dubravko Horvat , Sasa Ilijic , Anja Marunovic

Einstein field equations for anisotropic spheres are solved and exact interior solutions obtained. This paper extends earlier treatments to include anisotropic models which accommodate a wider variety of physically viable energy densities.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Chaisi , S. D. Maharaj

We investigate the effect of density perturbations and local anisotropy on the stability of stellar matter structures in general relativity using the concept of cracking. Adopting a core-envelope model of a super-dense star, we examine the…

General Relativity and Quantum Cosmology · Physics 2026-05-05 A. C. Khunt , V. O. Thomas , P. C. Vinodkumar

We present a class of new relativistic solutions with anisotropic fluid for compact stars in hydrostatic equilibrium. The interior space-time geometry considered here for compact objects are described by parameters namely, $\lambda$, $k$,…

General Relativity and Quantum Cosmology · Physics 2016-03-25 Bikash Chandra Paul , Rumi Deb

We have performed a series of high resolution N-body experiments on a Connection Machine CM-5 in order to study the stability of collisionless self-gravitating spherical systems. We interpret our results in the framework of symplectic…

Astrophysics · Physics 2015-06-24 J. Perez , J-M Alimi , J-J Aly , H. Scholl

We investigate anisotropic compact stars in the non-minimal $Y(R)F^2$ model of gravity which couples an arbitrary function of curvature scalar $Y(R)$ to the electromagnetic field invariant $F^2$. After we obtain exact anisotropic solutions…

General Relativity and Quantum Cosmology · Physics 2018-10-17 Özcan Sert , Fatma Çeliktaş , Muzaffer Adak

Following earlier authors, we re-examine constraints on the radial velocity anisotropy of generic stellar systems using arguments for phase space density positivity, stability, and separability. It is known that although the majority of…

Astrophysics of Galaxies · Physics 2015-06-19 Jeremy A. Barber , Hongsheng Zhao

A main question in astrophysics and cosmology has been the severe stability of the astrophysical objects, whether a particular equilibrium configuration is stable. In this article, we study the relativistic self-gravitating, hydrostatic…

General Relativity and Quantum Cosmology · Physics 2022-03-23 A. S. Saad , M. I. Nouh , A. A. Shaker , T. M. Kamel

We introduce a rigorous and general framework to study systematically self-gravitating elastic materials within general relativity, and apply it to investigate the existence and viability, including radial stability, of spherically…

General Relativity and Quantum Cosmology · Physics 2022-06-07 Artur Alho , José Natário , Paolo Pani , Guilherme Raposo

We study nonaxisymmetric perturbations of rotating relativistic stars. modeled as perfect-fluid equilibria. Instability to a mode with angular dependence $\exp(im\phi)$ sets in when the frequency of the mode vanishes. The locations of these…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Nikolaos Stergioulas , John L. Friedman

This paper is an investigation of the stability of some ideal stars. It is in- tended as a study in General Relativity, with emphasis on the coupling to matter, eventually aimed at a better understanding of very strong gravitational fields…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Christian Fronsdal

The equilibrium configurations of slowly rotating anisotropic self-gravitating fluids are computed using the extended Hartle structure equations, including anisotropic effects, derived in our previous paper. We focus on the so-called…

General Relativity and Quantum Cosmology · Physics 2025-10-20 Philip Beltracchi , Camilo Posada

In this work we construct families of anisotropic neutron stars for an equation of state compatible with the constraints of the gravitational-wave event GW170817 and for four anisotropy ansatze. Such stars are subjected to a radial…

General Relativity and Quantum Cosmology · Physics 2020-08-13 Juan M. Z. Pretel

Anisotropic stresses are ubiquitous in nature, but their modeling in General Relativity is poorly understood and frame dependent. We introduce the first study on the dynamical properties of anisotropic self-gravitating fluids in a covariant…

General Relativity and Quantum Cosmology · Physics 2019-06-05 Guilherme Raposo , Paolo Pani , Miguel Bezares , Carlos Palenzuela , Vitor Cardoso

Our manuscript aims to analysis the viability and stability of anisotropic stellar objects in the modified symmetric teleparallel gravity. A particular model of this extended theory is considered to formulate explicit field equations which…

General Relativity and Quantum Cosmology · Physics 2024-08-29 M. Zeeshan Gul , M. Sharif , Adeeba Arooj

The study of perturbation of self-gravitating celestial cylindrical object have been carried out in this paper. We have designed a framework to construct the collapse equation by formulating the modified field equations with the background…

General Physics · Physics 2017-11-08 M. Zaeem-ul-Haq Bhatti , Z. Yousaf

We obtain bounds on the stability of various self-gravitating astrophysical objects using a new measure of shape complexity known as configurational entropy. We apply the method to Newtonian polytropes, neutron stars with an…

General Relativity and Quantum Cosmology · Physics 2016-07-06 Marcelo Gleiser , Nan Jiang

We derive upper and lower limits for the basic physical parameters (mass-radius ratio, anisotropy, redshift and total energy) for arbitrary anisotropic general relativistic matter distributions in the presence of a cosmological constant.…

General Relativity and Quantum Cosmology · Physics 2007-05-23 C. G. Boehmer , T. Harko

Dev (2002) discussed some exact solutions of anisotropic stars for special forms of TOV for constant energy density. Considering Bijalwan (2011) ansatz for charged perfect fluids we present here some exact solutions to the generalized TOV…

General Physics · Physics 2011-09-26 Naveen Bijalwan

In this paper, we consider the mimetic gravitational theory to derive a novel category of anisotropic star models. To end and to put the resulting differential equations into a closed system, the form of the metric potential $g_{rr}$ as…

General Relativity and Quantum Cosmology · Physics 2021-10-11 G. G. L. Nashed