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Related papers: Gravastars must have anisotropic pressures

200 papers

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

Gravastars, theoretical alternatives to black holes, have captured the interest of scientists in astrophysics due to their unique properties. This paper aims to further investigate the exact solution of a novel gravastar model based on the…

General Relativity and Quantum Cosmology · Physics 2024-05-01 Faisal Javed , Ji Lin

The crucial role played by pressure in general relativity is explored in the mathematically simple context of a static spherically symmetric geometry. By keeping all pressure terms, the standard formalisms of rotation curve and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Tristan Faber

In this paper, we investigate a new model of $(2+1)-$dimensional ($3D$) gravitational vacuum stars (gravastars) with an isotropic matter distribution anti-de Sitter (AdS) spacetime in the context of massive gravity. For this purpose, we…

General Relativity and Quantum Cosmology · Physics 2023-10-30 H. Barzegar , B. Eslam Panah , G. H. Bordbar , M. Bigdeli

Gravastars have been recently proposed as potential alternatives to explain the astrophysical phenomenology traditionally associated to black holes, raising the question of whether the two objects can be distinguished at all. Leaving aside…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Cecilia B. M. H. Chirenti , Luciano Rezzolla

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

We combine the ideas of a Weyl scaling invariant dark energy action, which eliminates black hole horizons, with the ``gravastar'' idea of a jump in the hole interior from a normal matter equation of state to an equation of state where…

General Relativity and Quantum Cosmology · Physics 2023-02-22 Stephen L. Adler

Regular black holes and horizonless black-hole mimickers offer mathematically consistent alternatives to address the challenges posed by standard black holes. However, the formation mechanism of these alternative objects is still largely…

General Relativity and Quantum Cosmology · Physics 2025-09-22 Daniel Jampolski , Luciano Rezzolla

We study spherically symmetric static spacetimes generally filled with an anisotropic fluid in the nonrelativistic general covariant theory of gravity. In particular, we find that the vacuum solutions are not unique, and can be expressed in…

High Energy Physics - Theory · Physics 2011-01-27 Jared Greenwald , V. H. Satheeshkumar , Anzhong Wang

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

Gravastars are considered as one of the prime exotic type compact objects which may be found at the end state of gravitational collapse of massive stars with a view to resolve the complexities that are pertinent in case of a black hole…

General Relativity and Quantum Cosmology · Physics 2024-08-22 Debadri Bhattacharjee , Pradip Kumar Chattopadhyay

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

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

In the last few decades, gravastars have been proposed as an alternative to black holes. The stability of the gravastar has been studied in many modified theories of gravity along with Einstein's GR. The $f(Q,T)$ gravity, a successfully…

General Relativity and Quantum Cosmology · Physics 2023-08-09 Sneha Pradhan , Debasmita Mohanty , P. K. Sahoo

In this article, we are reporting for the first time the existence of gravastar configurations in the framework of K(R,T)-gravity, which can be treated as an alternative to a black hole (Mazur and Mottola). This strengthens how much this…

General Relativity and Quantum Cosmology · Physics 2023-08-22 GRP Teruel , Ksh. Newton Singh , Tanmoy Chowdhury , Farook Rahaman , Monimala Mondal

In this paper, we investigate models of radiating gravastars with both isotropic and anisotropic interiors, incorporating various types of thin shell matter. For the isotropic interior case, we consider a thin spherical shell characterized…

General Relativity and Quantum Cosmology · Physics 2024-08-20 Hasan Al-Asy'ari , Fiki Taufik Akbar , Bobby Eka Gunara

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 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

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

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