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Related papers: Cosmological tests of the gravastar hypothesis

200 papers

In this work, we analyze the observational properties of thin-shell gravastars under two astrophysical frameworks, namely surrounded by optically-thin accretion disks and orbited by hot-spots. We consider the thin-shell gravastar model with…

General Relativity and Quantum Cosmology · Physics 2024-04-02 João Luís Rosa , Daniela S. J. Cordeiro , Caio F. B. Macedo , Francisco S. N. Lobo

In this paper we investigate the gravitational vacuum stars which called gravastars in the non-minimally coupled models with electromagnetic and gravitational fields. We consider two non-minimal models and find the corresponding spherically…

General Relativity and Quantum Cosmology · Physics 2021-11-18 Özcan Sert , Muzaffer Adak

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

The gravastar is an exotic compact object proposed as a final product of gravitational collapse of a massive object in order to resolve problems associated with black holes. It is enclosed by a thin crust and the inside of it is occupied by…

General Relativity and Quantum Cosmology · Physics 2023-05-03 Ken-ichi Nakao , Kazumasa Okabayashi , Tomohiro Harada

We study the gravitational vacuum star (gravastar) configuration as proposed by other authors in a model where the interior de Sitter spacetime segment is continuously extended to the exterior Schwarzschild spacetime. The multilayered…

General Relativity and Quantum Cosmology · Physics 2007-06-19 A. DeBenedictis , D. Horvat , S. Ilijic , S. Kloster , K. S. Viswanathan

A new final state of gravitational collapse is proposed. By extending the concept of Bose-Einstein condensation to gravitational systems, a cold, dark, compact object with an interior de Sitter condensate $p_{_V} = -\rho_{_V}$ and an…

General Relativity and Quantum Cosmology · Physics 2009-10-19 Pawel O. Mazur , Emil Mottola

This paper studies the effects of charge on a peculiar stellar object, recognized as gravastar, under the influence of $f(R,T)$ gravity by considering the conjecture of Mazur and Mottola in general relativity. The gravastar is also known as…

General Relativity and Quantum Cosmology · Physics 2019-11-27 M. Sharif , Arfa Waseem

In this thesis, we consider two different problems relevant to general relativity. Over the last few years, opinions on physically relevant singularities occurring in FRW cosmologies have considerably changed. We present an extensive…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Celine Cattoen

We present a new model of gravastar in the higher dimensional Einsteinian spacetime including Einstein's cosmological constant $\Lambda$. Following Mazur and Mottola (2001,~2004) we obtain a set of solutions for gravastar. This gravastar is…

General Relativity and Quantum Cosmology · Physics 2018-05-22 Shounak Ghosh , Saibal Ray , Farook Rahaman , B. K. Guha

The cosmological evolution of the binary black hole (BH) merger rate and the energy density of the gravitational-wave (GW) background are investigated. To evaluate the redshift dependence of the BH formation rate, BHs are assumed to…

High Energy Astrophysical Phenomena · Physics 2016-11-30 Ken'ichiro Nakazato , Yuu Niino , Norichika Sago

The low energy effective theory of gravity comprises two elements of quantum theory joined to classical general relativity. The first is the quantum conformal anomaly, which is responsible for macroscopic correlations on light cones and a…

General Relativity and Quantum Cosmology · Physics 2025-02-05 Emil Mottola

One of the very small number of serious alternatives to the usual concept of an astrophysical black hole is the "gravastar" model developed by Mazur and Mottola; and a related phase-transition model due to Laughlin et al. We consider a…

General Relativity and Quantum Cosmology · Physics 2009-04-17 Celine Cattoen , Tristan Faber , Matt Visser

In the current research, we present a novel gravastar model based on the Mazur-Mottola (2004) method with an isotropic matter distribution in $f(Q)$ gravity. The gravastar, a hypothesized substitute for a black hole, is built using the…

General Relativity and Quantum Cosmology · Physics 2023-04-12 Sneha Pradhan , Sanjay Mandal , P. K. Sahoo

We analyze the evolution of a homogenous and pressureless ball of dust (or "star") in ghost-free massive gravity on de Sitter spacetime. We find that gravitational collapse does not take place for all parameters of the massive gravity…

High Energy Physics - Theory · Physics 2021-09-23 Roman Berens , Luke Krauth , Rachel A. Rosen

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

This study analyzes the physical features of a gravastar within the $f(\mathcal{Q}, \mathbb{T})$ gravity framework, where $\mathcal{Q}$ is the non-metricity scalar and $\mathbb{T}$ is the trace of the energy-momentum tensor. Gravastars…

General Relativity and Quantum Cosmology · Physics 2025-02-17 Iqra Ibrar , M. Sharif

This paper discusses the configuration of gravitational vacuum star or gravastar with the impact of geometry and matter coupling present in $f(R,T)$ gravity. The gravastar is also conceptualized as a substitute for a black hole which is…

General Relativity and Quantum Cosmology · Physics 2020-12-07 M. Sharif , Arfa Waseem

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

Gravastars, hypothetic astrophysical objects, consisting of a dark energy condensate surrounded by a strongly correlated thin shell of anisotropic matter, have been proposed as an alternative to the standard black hole picture of general…

General Relativity and Quantum Cosmology · Physics 2009-10-06 Tiberiu Harko , Zoltán Kovács , Francisco S. N. Lobo

A certain vector-tensor (VT) theory of gravitation was tested in previous papers. In the background universe, the vector field of the theory has a certain energy density, which is appropriate to play the role of vacuum energy (cosmological…

General Relativity and Quantum Cosmology · Physics 2015-09-15 Roberto Dale , Màrius J. Fullana , Diego Sáez