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Related papers: Gravastars must have anisotropic pressures

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In this paper, model of charged gravastar under $f(T)$ modified gravity is obtained. The model has been explored by taking the diagonal tetrad field of static spacetime together with electric charge. To solve the Einstein-Maxwell field…

General Relativity and Quantum Cosmology · Physics 2021-06-18 Piyali Bhar , Pramit Rej

We present a new system of equations that fully characterizes adiabatic, radial perturbations of perfect fluid stars within the theory of general relativity. The properties of the system are discussed, and, provided that the equilibrium…

General Relativity and Quantum Cosmology · Physics 2024-05-14 Paulo Luz , Sante Carloni

Gravitational vacuum condensate stars, also known as gravastars, have been proposed as an alternative to black holes. Their interior contains a perfect fluid with an equation of state akin to that of a cosmological constant. For this…

General Relativity and Quantum Cosmology · Physics 2023-08-16 P. P. Avelino

We examine spherical gravitational collapse of a matter model with vanishing radial pressure and non-zero tangential pressure. It is seen analytically that the collapsing cloud either forms a black hole or disperses depending on values of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ashutosh Mahajan , Pankaj S. Joshi

Within the metric formalism of $f(R)$ theories of gravity, where $R$ is the Ricci scalar, we study the hydrostatic equilibrium structure of compact stars with the inclusion of anisotropic pressure. In particular, we focus on the $f(R)=…

General Relativity and Quantum Cosmology · Physics 2022-07-11 Juan M. Z. Pretel , Sergio B. Duarte

In this paper, we are interested to explore stable configurations of $d$-dimensional gravastars constructed from the interior $d$-dimensional de Sitter and exterior $d$-dimensional Schwarzschild/Reissner-Nordstr\"om (de Sitter) black holes…

General Relativity and Quantum Cosmology · Physics 2022-05-10 M. Sharif , Faisal Javed

This paper is the first in a sequence of three devoted to the formulation of a theory of self-gravitating anisotropic fluids in both Newtonian and relativistic gravity. In this first paper we set the stage, place our work in the context of…

General Relativity and Quantum Cosmology · Physics 2024-06-06 Tom Cadogan , Eric Poisson

The trace-free Einstein equations contain one equation less than the complete field equations. In a static and spherically symmetric spacetime, the number of field equations is thus reduced to two. The equation of pressure isotropy of…

General Relativity and Quantum Cosmology · Physics 2024-03-27 Sudan Hansraj , Chevarra Hansraj , Njabulo Mkhize , Abdelghani Errehymy , Christian G. Boehmer

In this paper we present a strange stellar model using Tolman $V$ type metric potential employing simplest form of the MIT bag equation of state (EOS) for the quark matter. We consider that the stellar system is spherically symmetric,…

General Relativity and Quantum Cosmology · Physics 2018-08-08 Dibyendu Shee , Debabrata Deb , Shounak Ghosh , Saibal Ray , B. k. Guha

We numerically obtain gravastar solutions as nontopological solitons in a system that consists of a U(1) gauge Higgs model with a complex scalar field and Einstein gravity. The solitonic gravastar solutions are compact enough to have a…

High Energy Physics - Theory · Physics 2023-06-28 Tatsuya Ogawa , Hideki Ishihara

We consider neutron-star-plus-wormhole configurations supported by a massless ghost scalar field. The neutron fluid is modeled by an anisotropic equation of state. When the central energy density of the fluid is of comparable magnitude to…

General Relativity and Quantum Cosmology · Physics 2014-04-15 Vladimir Dzhunushaliev , Vladimir Folomeev , Burkhard Kleihaus , Jutta Kunz

We present a class of exact solutions of Einstein's gravitational field equations describing spherically symmetric and static anisotropic stellar type configurations. The solutions are obtained by assuming a particular form of the…

General Relativity and Quantum Cosmology · Physics 2017-10-04 T. Harko , M. K. Mak

We consider a configuration consisting of a wormhole filled by a perfect fluid. Such a model can be applied to describe stars as well as neutron stars with a nontrivial topology. The presence of a tunnel allows for motion of the fluid,…

Astrophysics of Galaxies · Physics 2015-05-27 V. Dzhunushaliev , V. Folomeev , B. Kleihaus , J. Kunz

The concept of dark energy can be a candidate for preventing the gravitational collapse of compact objects to singularities. According to the usefulness of gravity's rainbow in UV completion of general relativity (by providing a new…

General Relativity and Quantum Cosmology · Physics 2022-10-25 A. Bagheri Tudeshki , G. H. Bordbar , B. Eslam Panah

A static, spherically symmetric spacetime with negative pressures is conjectured inside a star. The gravitational field is repulsive and so a central singularity is avoided. The positive energy density and the pressures of the imperfect…

General Relativity and Quantum Cosmology · Physics 2020-05-05 Hristu Culetu

In this work, we investigate an anisotropic compact star's physical properties and stability in F(Q) gravity. The study focuses on the significance of F(Q) gravity on the structure and stability of compact star, considering non-perfect…

General Relativity and Quantum Cosmology · Physics 2024-09-26 Sat Paul , Jitendra Kumar , Sunil Kumar Maurya , Sourav Choudhary , Sweeti Kiroriwala

In this work, we examine a spherically symmetric compact body with isotropic pressure profile, in this context we obtain a new class of exact solutions of Einstein's-Maxwell field equation for compact stars with uniform charged…

General Physics · Physics 2021-04-28 Amit Kumar Prasad , Jitendra Kumar

In this paper, we investigate the fluid/gravity correspondence in spacetime with general non-rotating weakly isolated horizon. With the help of Petrov-like boundary condition and large mean curvature limit, we show that the dual…

High Energy Physics - Theory · Physics 2015-06-15 Xiaoning Wu , Yi Ling , Yu Tian , Chengyong Zhang

Low surface brightness galaxies are an excellent laboratory where stars and baryonic matter act as tracers of the gravitational potential of the dark matter halo. If dark matter is modeled as a perfect fluid, then spherically symmetric and…

Astrophysics of Galaxies · Physics 2024-08-29 Andrés Aceña , Juan Barranco , Argelia Bernal , Ericson López , Mario Llerena

Recent studies have shown that dark matter halos can support regular black holes or compact stars by assuming an anisotropic energy-momentum tensor. In this paper, we extend the analysis to the dark matter halo as an isotropic perfect…

General Relativity and Quantum Cosmology · Physics 2026-01-30 Yuan Yue , Yong-Qiang Wang