English
Related papers

Related papers: Stable dark energy stars

200 papers

A gravastar comprises three distinct sections: the interior zone, the middle shell, and its outer region. By considering a specific extended teleparallel gravity model that incorporates conformal Killing vectors and provides the field…

General Relativity and Quantum Cosmology · Physics 2024-04-30 G. Mustafa , Faisal Javed , Arfa Waseem , S. K. Maurya , Ghulam Fatima

We propose a stellar model under the $f(\mathbb{T},\mathcal{T})$ gravity following Mazur-Mottola's conjecture [Mazur (2001), Mazur (2004)] known as gravastar which is generally believed as a viable alternative to black hole. The gravastar…

General Relativity and Quantum Cosmology · Physics 2020-03-09 Shounak Ghosh , A. D. Kanfon , Amit Das , M. J. S. Houndjo , I. G. Salako , Saibal Ray

We solve Einstein's equations for slowly-rotating gravitational condensate stars (gravastars) up to second order in the rotation by expanding about the spherically symmetric gravastar with de Sitter interior and Schwarzschild exterior…

General Relativity and Quantum Cosmology · Physics 2022-01-12 Philip Beltracchi , Paolo Gondolo , Emil Mottola

In this work, we discuss the configuration of a gravastar (gravitational vacuum stars) in the context of $f(R, \,T )$ gravity by employing the Mazur-Mottola conjecture [P. Mazur and E. Mottola, Report No. LA-UR-01-5067; P. Mazur and E.…

General Relativity and Quantum Cosmology · Physics 2021-08-26 Piyali Bhar , Pramit Rej

We consider the gravastar model where the vacuum phase transition between the de Sitter interior and the Schwarzschild or Schwarzschild-de Sitter exterior geometries takes place at a single spherical delta-shell. We derive sharp analytic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Dubravko Horvat , Sasa Ilijic

Black holes are normally and naturally associated to the end-point of gravitational collapse. Yet, alternatives have been proposed and a particularly interesting one is that of gravitational condensate stars, or gravastars. We here revisit…

General Relativity and Quantum Cosmology · Physics 2024-02-20 Daniel Jampolski , Luciano Rezzolla

Here we generalized a previous model of gravastar consisted of an internal de Sitter spacetime, a dynamical infinitely thin shell with an equation of state, but now we consider an external de Sitter-Schwarzschild spacetime. We have shown…

General Relativity and Quantum Cosmology · Physics 2012-10-25 R. Chan , M. F. A. da Silva , P. Rocha

Spherical energy shells in General Relativity tend to collapse due to gravitational effects and/or due to tension effects. Shell stabilization may be achieved by modifying the gravitational properties of the background spacetime. Thus,…

General Relativity and Quantum Cosmology · Physics 2022-08-17 I. Antoniou , D. Kazanas , D. Papadopoulos , L. Perivolaropoulos

In this paper, we have extended the idea of gravitational Bose-Einstein condensate star (gravastar) to charged gravastar system and explored the role of charge in gravastar formation and its properties. We have used the most general line…

General Relativity and Quantum Cosmology · Physics 2023-08-25 D. Bhattacharjee , P. K. Chattopadhyay

Gravastars have been considered as a feasible alternative to black holes in the past couple of decades. Stable models of gravastar have been studied in many of the alternative gravity theories besides standard General Relativity (GR). The…

General Relativity and Quantum Cosmology · Physics 2021-07-14 Shounak Ghosh , Sagar Dey , Amit Das , Anirban Chanda , B C Paul

A new model of gravastar is obtained in $D$-dimensional Einstein gravity. This class of solutions includes the gravastar as an alternative to D-dimensional versions of the Schwarzschild-Tangherlini black hole. The configuration of this new…

General Physics · Physics 2014-06-04 Farook Rahaman , Subenoy Chakraborty , Saibal Ray , A. A. Usmani , Safiqul Islam

Direct observation of black holes is one of the grand challenges in astronomy. If there are super-compact objects which possess unstable circular orbits of photons, however, it may be difficult to distinguish them from black holes by…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Nobuyuki Sakai , Hiromi Saida , Takashi Tamaki

The existence of cosmological compact objects with very strong gravity is a prediction of General Relativity and an exact solution of the Einstein equations. These objects are called black holes and recently we had the first observations of…

General Relativity and Quantum Cosmology · Physics 2022-12-09 Ioannis Antoniou

We consider a gravastar model made of anisotropic dark energy with an infinitely thin spherical shell of a perfect fluid with the equation of state $p = (1-\gamma)\sigma$ with an external de Sitter-Schwarzschild region. It is found that in…

General Relativity and Quantum Cosmology · Physics 2015-03-17 C. F. C. Brandt , R. Chan , M. F. A. da Silva , P. Rocha

Gravastars are configurations of compact singularity-free gravitational objects which are interesting alternatives to classical solutions in the strong gravitational field regime. Although there are no static star-like solutions of the…

General Relativity and Quantum Cosmology · Physics 2021-11-03 Alejandro Cabo Montes de Oca , Duvier Suarez Fontanella , David Valls-Gabaud

We consider a gravastar model made of anisotropic dark energy with an infinitely thin spherical shell of a perfect fluid with the equation of state $p = (1-\gamma)\sigma$ with an external de Sitter-Schwarzschild region. It is found that in…

General Relativity and Quantum Cosmology · Physics 2015-03-19 R. Chan , M. F. A. da Silva , P. Senna , J. F. Villas da Rocha

We represent a class of new Gravastar solutions as obtained by Mazur and Mottola in a gravitational Bose-Einstein condensate (GBEC) in a cylindrical symmetric space-time. A stable gravastar with three distinct regions namely, (i) Interior…

General Relativity and Quantum Cosmology · Physics 2023-12-27 D. Bhattacharjee , P. K. Chattopadhyay , B. C. Paul

Gravitational vacuum condensate stars, proposed as the endpoint of gravitational collapse consistent with quantum theory, are reviewed. Gravastars are cold, low entropy, maximally compact objects characterized by a surface boundary layer…

General Relativity and Quantum Cosmology · Physics 2023-11-28 Emil Mottola

Gravitational vacuum stars (gravastars) have become a viable theoretical alternative to the black hole (BH) end-stage of stellar evolution. These objects gravitate in vacuum like BHs, yet have no event horizons. In this paper, we present…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-05 K. A. S. Croker

We propose a class of models, in which stable gravastar with large surface redshift becomes a solution. In recent decades, gravastars have become a plausible substitute for black holes. Researchers have explored stable gravastar models in…

General Relativity and Quantum Cosmology · Physics 2024-01-31 Shin'ichi Nojiri , G. G. L. Nashed