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Related papers: Cosmological tests of the gravastar hypothesis

200 papers

A new solution for the endpoint of gravitational collapse is proposed. By extending the concept of Bose-Einstein condensation to gravitational systems, a cold, compact object with an interior de Sitter condensate phase and an exterior…

General Relativity and Quantum Cosmology · Physics 2023-02-16 Pawel O. Mazur , Emil Mottola

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

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

In this paper, we discuss some feasible features of gravastar that were firstly demonstrated by Mazur and Mottola. It is already established that gravastar associates the de-Sitter spacetime in its inner sector with the Schwarzschild…

General Relativity and Quantum Cosmology · Physics 2020-05-05 M. Z. Bhatti , Z. Yousaf , A. Rehman

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

In this work we derive a gravastar model in Randall-Sundrum II braneworld scenario. Gravastars (or gravitationally vacuum stars) were proposed by Mazur and Mottola as systems of gravitational collapse alternative to black holes. The…

General Relativity and Quantum Cosmology · Physics 2019-10-08 José D V Arbañil , Pedro H R S Moraes , Manuel Malheiro

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

The "gravastar" picture developed by Mazur and Mottola is one of a very small number of serious challenges to our usual conception of a "black hole". In the gravastar picture there is effectively a phase transition at/ near where the event…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Matt Visser , David L. Wiltshire

In recent work we physically interpreted a special gravastar solution characterized by a zero Schwarzschild mass. In fact, in that case, none gravastar was formed and the shell expanded, leaving behind a de Sitter or a Minkowski spacetime,…

General Relativity and Quantum Cosmology · Physics 2011-09-23 R. Chan , M. F. A. da Silva

We construct the solutions of slowly rotating gravastars with a thin shell. In the zero-rotation limit, we consider the gravastar composed of a de Sitter core, a thin shell, and Schwarzschild exterior spacetime. The rotational effects are…

General Relativity and Quantum Cosmology · Physics 2016-01-13 Nami Uchikata , Shijun Yoshida

This study explores the effect of charge on a special astronomical object known as a gravastar, which is viewed as an alternative to a black hole. Based on the conjecture put out by Mazur and Mottola in general relativity, the study…

General Relativity and Quantum Cosmology · Physics 2024-05-01 Faisal Javed , Arfa Waseem , G. Mustafa , Fairouz Tchier , Farruh Atamurotov , Bobomurat Ahmedov , Ahmadjon Abdujabbarov

Dynamical models of prototype gravastars are constructed and studied. The models are the Visser-Wiltshire three-layer gravastars, in which an infinitely thin spherical shell of a perfect fluid with the equation of state $p =…

General Relativity and Quantum Cosmology · Physics 2009-03-27 P. Rocha , R. Chan , M. F. A. da Silva , Anzhong Wang

Dynamical Dark Energy (DE) is a viable alternative to the cosmological constant. Yet, constructing tests to discriminate between Lambda and dynamical DE models is difficult because the differences are not large. In this paper we explore…

Astrophysics · Physics 2009-11-10 P. Solevi , R. Mainini , S. A. Bonometto , A. V. Maccio' , A. Klypin , S. Gottloeber

In this work, we investigate gravastar-like structures in static and spherically symmetric space-time within the framework of $f(Q)$ gravity coupled with conformal symmetry. We have modified the conventional gravastar model by introducing a…

General Relativity and Quantum Cosmology · Physics 2025-05-26 Debadri Bhattacharjee , Pradip Kumar Chattopadhyay

The discovery of cosmic acceleration has presented a unique challenge for cosmologists. As observational cosmology forges ahead, theorists have struggled to make sense of a standard model that requires extreme fine tuning. This challenge is…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-02 Chanda Prescod-Weinstein , Niayesh Afshordi , Michael L. Balogh

The multipole moments and the tidal Love numbers of neutron stars and quark stars satisfy certain relations which are almost insensitive to the star's internal structure. A natural question is whether the same relations hold for different…

General Relativity and Quantum Cosmology · Physics 2017-01-24 Paolo Pani

This manuscript explores the gravastar model in the $f(R,\Sigma,T)$ gravity framework, with the help of Kuchowicz metric funcition, offering an alternative to black holes. A gravastar has three regions: interior, intermediate shell, and…

General Relativity and Quantum Cosmology · Physics 2025-09-05 Bharat Singh , S. Surendra Singh

In this paper we consider the Dvali and G\'omez assumption that the end state of a gravitational collapse is a Bose-Einstein condensate of gravitons. We then construct the two Gross-Pitaevskii equations for a static and spherically…

General Relativity and Quantum Cosmology · Physics 2018-05-02 Francesc Cunillera , Cristiano Germani

The horizonless configuration of regular black holes has recently attracted attention as a model for ultracompact stars. In this paper, we propose a new class of regular black hole models sourced by a de Sitter vacuum with a finite radius.…

General Relativity and Quantum Cosmology · Physics 2025-08-27 M. F. Fauzi , B. N. Jayawiguna , H. S. Ramadhan , A. Sulaksono

We present a stationary spherically symmetric solution of the Einstein equations, with a source generated by a scalar field of $q$-theory. In this theory Riemannian gravity, as described by the Einstein - Hilbert action, is coupled to a…

General Relativity and Quantum Cosmology · Physics 2023-07-26 M. Selch , J. Miller , M. A. Zubkov