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Related papers: Study of Gravastars in Rastall Gravity

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The physical properties of a (3+1)-D gravastar in the context of massive gravity are discussed in this work. In present investigation, the field equations have been solved for a static, uncharged sphere in order to achieve the gravastar…

General Relativity and Quantum Cosmology · Physics 2024-04-10 Piyali Bhar

One of the main challenges in astronomy is the direct observation of black holes. However, differentiating them from black holes through photon observations can be difficult if Ultra-Compact Objects with unstable circular photon orbits…

General Relativity and Quantum Cosmology · Physics 2026-05-06 M. A. Anacleto , A. T. N. Silva , L. Casarini

Astrophysical black holes arise as exact solutions of the Einstein field equations. Therefore, any alternative, such as a gravastar, must satisfy the same level of mathematical rigor and internal consistency. A physically viable gravastar…

General Relativity and Quantum Cosmology · Physics 2026-04-14 Farook Rahaman , Bikramarka S. Choudhury , Aritra Sanyal , Anikul Islam , Bidisha Samanta

Dynamical models of prototype gravastars were constructed in order to study their stability. The models are the Visser-Wiltshire three-layer gravastars, in which an infinitely thin spherical shell of stiff fluid divides the whole spacetime…

General Relativity and Quantum Cosmology · Physics 2011-03-28 P. Rocha , A. Y. Miguelote , R. Chan , M. F. da Silva , N. O. Santos , Anzhong Wang

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

In this paper we construct a charged thin-shell gravastar model within the context of noncommutative geometry. To do so, we choose the interior of the nonsingular de Sitter spacetime with an exterior charged noncommutative solution by…

General Relativity and Quantum Cosmology · Physics 2017-08-24 Ali Övgün , Ayan Banerjee , Kimet Jusufi

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

Using the conventional gravastar model, that is, an object constituted by two components where one of them is a massive infinitely thin shell and the other one is a de Sitter interior spacetime, we physically interpret a solution…

General Relativity and Quantum Cosmology · Physics 2012-10-30 R. Chan , M. F. A. da Silva , Jaime F. Villas da Rocha

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

This is a continuation and generalization of our earlier work on {\it gravastar} in (2+1) anti-de Sitter space-time to 2+1 dimensional solution of charged gravastar. Morphologically this gravastar contains three regions namely: (i) charged…

General Physics · Physics 2015-06-05 Farook Rahaman , A. A. Usmani , Saibal Ray , Safiqul Islam

In this article, we study the properties of charged gravastars in torsion-based $f(\mathbb{T})$ gravity in the presence of noncommutative geometry. We have taken the interior from noncommutative motivated space-time, noting that why, from a…

General Relativity and Quantum Cosmology · Physics 2024-10-21 Debasmita Mohanty , Sayantan Ghosh , P. K. Sahoo

In recent days gravastar has been a very lucrative alternative to black holes, as it does not suffer from the singularity problem as well and it is based on sound physical grounds. Modified Symmetric teleparallel equivalent of gravity also…

General Relativity and Quantum Cosmology · Physics 2024-03-05 Debasmita Mohanty , Sayantan Ghosh , P. K. Sahoo

This paper explores the possible existence of stable regions of bounded excursion gravastars in the background of regular black holes (Bardeen and Bardeen-de Sitter black holes). For this purpose, we match internal de Sitter geometry with…

General Relativity and Quantum Cosmology · Physics 2021-11-17 M. Sharif , Faisal Javed

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 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

Gravastar models have recently been proposed as an alternative to black holes, mainly to avoid the problematic issues associated with event horizons and singularities. In this work, a wide variety of gravastar models within the context of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Francisco S. N. Lobo , Aaron V. B. Arellano

A promising theory in modifying general relativity by violating the ordinary energy-momentum conservation law in curved spacetime is the Rastall theory of gravity. In this theory, geometry and matter fields are coupled to each other in a…

General Relativity and Quantum Cosmology · Physics 2018-03-12 Iarley P. Lobo , H. Moradpour , J. P. Morais Graça , I. G. Salako

Rastall gravity, originally developed in 1972, is currently undergoing a significant surge in popularity. Rastall gravity purports to be a modified theory of gravity, with a non-conserved stress-energy tensor, and an unusual non-minimal…

General Relativity and Quantum Cosmology · Physics 2018-05-30 Matt Visser

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

Considering a Vaidya exterior spacetime, we study dynamical models of prototype gravastars, made of an infinitely thin spherical shell of a perfect fluid with the equation of state $p = \sigma$, enclosing an interior de Sitter spacetime. We…

General Relativity and Quantum Cosmology · Physics 2012-10-22 R. Chan , M. F. A. da Silva , J. F. Villas da Rocha , Anzhong Wang