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Related papers: Gravastar Shadows

200 papers

We consider spherically symmetric black holes with minimally coupled scalar fields and concentrate our attention on asymptotically flat self-gravitating configurations having the event horizons located at radii much smaller than $2m$. We…

General Relativity and Quantum Cosmology · Physics 2019-12-10 I. M. Potashov , Ju. V. Tchemarina , A. N. Tsirulev

If a traversable wormhole smoothly connects two different spacetimes, then the flux cannot be separately conserved in any of these spaces individually. Then objects propagating in a vicinity of a wormhole in one space must feel influence of…

General Relativity and Quantum Cosmology · Physics 2020-04-07 De-Chang Dai , Dejan Stojkovic

This work aims to explore the gravitational consequences of a recently proposed black hole solution presented in the literature [Phys. Dark Univ. 50 (2025) 102061]. We initiate our analyzes by taking into account the horizon structure,…

General Relativity and Quantum Cosmology · Physics 2025-09-18 A. A. Araújo Filho , N. Heidari , Iarley P. Lobo

We employ the minimal geometric deformation approach to gravitational decoupling (MGD-decoupling) in order to generate an exact anisotropic and non-uniform version of the ultracompact Schwarzschild star, or 'gravastar', proposed by Mazur…

General Relativity and Quantum Cosmology · Physics 2020-09-25 J. Ovalle , C. Posada , Z. Stuchlík

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

Gravitational-wave observations of compact binaries have the potential to uncover the distribution of masses and angular momenta of black holes and neutron stars in the universe. The binary components' physical parameters can be inferred…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Mark Hannam , Duncan A. Brown , Stephen Fairhurst , Chris L. Fryer , Ian W. Harry

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

Astrophysical black hole candidates, although long thought to have a horizon, could be horizonless ultra-compact objects. This intriguing possibility is motivated by the black hole information paradox and a plausible fundamental connection…

General Relativity and Quantum Cosmology · Physics 2017-04-26 Bob Holdom , Jing Ren

In its final year of inspiral, a stellar mass ($1 - 10 M_\odot$) body orbits a massive ($10^5 - 10^7 M_\odot$) compact object about $10^5$ times, spiralling from several Schwarzschild radii to the last stable orbit. These orbits are deep in…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Scott A. Hughes

The Event Horizon Telescope (EHT) has recently observed the image and shadow of the supermassive compact object Sagittarius A$^*$ (Sgr A$^*$). According to the EHT collaboration, the observed image is consistent with the expected appearance…

General Relativity and Quantum Cosmology · Physics 2023-05-29 Rajibul Shaikh

Rotating black holes can amplify ultralight bosonic fields through superradiance, forming macroscopic clouds known as gravitational atoms. When the cloud forms around one of the components of a binary system, it can undergo a series of…

General Relativity and Quantum Cosmology · Physics 2025-07-23 Riccardo Della Monica , Richard Brito

A rotating black hole can be clouded by light bosons via superradiance, and thus acquire an atom-like structure. If such a gravitational atom system is companioned with a pulsar, the pulsar can trigger transitions between energy levels of…

High Energy Astrophysical Phenomena · Physics 2022-01-26 Xi Tong , Yi Wang , Hui-Yu Zhu

Modified gravity theories capable of genuine self-acceleration typically invoke a galileon scalar which mediates a long range force, but is screened by the Vainshtein mechanism on small scales. In such theories, non-relativistic stars carry…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Lam Hui , Alberto Nicolis

Astrophysical black holes are usually surrounded by an accretion disk. At least parts of these accretion disks consist of a plasma in which light rays with different energies are dispersed. However, we usually do not know the exact…

General Relativity and Quantum Cosmology · Physics 2026-05-21 Torben C. Frost

We propose a way to distinguish compact stellar object, whose size is very close to its Schwarzschild radius, from the collapsing stars. Namely, we show that {\it massive} fields in the vicinity of a very compact stellar object have…

General Relativity and Quantum Cosmology · Physics 2016-03-09 Emil T. Akhmedov , Daniil A. Kalinov , Fedor K. Popov

This paper presents a study on gravitational vacuum stars (gravastars) with an isotropic matter distribution in de Rham-Gabadadze-Tolley (dRGT) massive gravity incorporating Buchdahl metric function. Here we have conducted an analysis on…

General Relativity and Quantum Cosmology · Physics 2025-06-16 Meghanil Sinha , S. Surendra Singh

New spherically symmetric gravastar solutions, stable to radial perturbations, are found by utilising the construction of Visser and Wiltshire. The solutions possess an anti--de Sitter or de Sitter interior and a Schwarzschild--(anti)--de…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Benedict M. N. Carter

We construct gravitational atoms including self-gravity, obtaining solutions of the Einstein-Klein-Gordon equations for a scalar field surrounding a non-rotating black hole in a quasi-stationary approximation. We resolve the region near the…

General Relativity and Quantum Cosmology · Physics 2025-10-23 Miguel Alcubierre , Juan Barranco , Argelia Bernal , Juan Carlos Degollado , Alberto Diez-Tejedor , Miguel Megevand , Darío Núñez , Olivier Sarbach

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

We investigate gravitational waves from a dust disk around a Schwarzschild black hole to focus on whether we can extract any of its physical properties from a direct detection of gravitational waves. We adopt a black hole perturbation…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Hajime Sotani , Motoyuki Saijo