English
Related papers

Related papers: Modeling Gravastar Structure admitting Kuchowicz S…

200 papers

We study an internal structure of (2+1)-dimensional black hole with the neutral scalar matter in the spherically symmetric geometry by using a quantum theory of gravity which holds in the both vicinities of the singularity and the apparent…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ichiro Oda

How can a Schwarzschild-sized matter system avoid a fate of gravitational collapse? To address this question, we critically reexamine the arguments that led to the "Buchdahl bound", which implies that the minimal size of a stable, compact…

High Energy Physics - Theory · Physics 2019-03-27 Ram Brustein , A. J. M. Medved

In this work, we investigate the static, spherically symmetric regular black hole solutions in a generalized Rastall gravity. In particular, the prescription of Rastall gravity implies that the present approach does not necessarily involve…

General Relativity and Quantum Cosmology · Physics 2019-07-25 Kai Lin , Wei-Liang Qian

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

We introduce a modification in the energy-momentum conservation violating Rastall's theory of gravity and obtain a Reissner-Nordstr\"om-type black hole solution in spacetime surrounded by a cloud of strings and charge fields. We examine the…

General Relativity and Quantum Cosmology · Physics 2024-04-11 Ronit Karmakar , Umananda Dev Goswami

We show that a generic relativistic membrane with in-plane pressure and surface density having the same sign is unstable with respect to a series of warping mode instabilities with high wave numbers. We also examine the criteria of…

General Relativity and Quantum Cosmology · Physics 2023-01-18 Huan Yang , Beatrice Bonga , Zhen Pan

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

Schwarzschild black holes are expected to emerge as the end states of the classical gravitational collapse from non-singular configurations. After integrable curvature singularities appear, the interior geometry can be modelled to exhibit a…

General Relativity and Quantum Cosmology · Physics 2026-05-15 Roberto Casadio , Andrea Giusti , Alexander Kamenshchik , Jorge Ovalle

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

We explore the construction of diverse regular spacetimes (black holes and defects) in General Relativity (GR) using a generic parametrised density profile (the Dekel-Zhao profile), which includes, for specific parameter choices, various…

General Relativity and Quantum Cosmology · Physics 2025-07-03 Anjan Kar , Sayan Kar

Rastall's theory belongs to the class of non-conservative theories of gravity. In vacuum, the only non-trivial static, spherically symmetric solution is the Schwarzschild one, except in a very special case. When a canonical scalar field is…

General Relativity and Quantum Cosmology · Physics 2017-03-03 K. A. Bronnikov , J. C. Fabris , O. F. Piattella , E. C. Santos

Rotating black hole solutions in theories of modified gravity are important as they offer an arena to test these theories through astrophysical observation. The non-rotating black hole can be hardly tested since the black hole spin is very…

General Relativity and Quantum Cosmology · Physics 2018-09-28 Rahul Kumar , Sushant G. Ghosh

In this work, we generalized the Kerr-Newman-NUT black hole solution in Rastall gravity from Ref. 1. Here we are more focused on the black hole dynamics such as the event horizons, ergosurface, ZAMO, thermodynamic properties, and the…

General Relativity and Quantum Cosmology · Physics 2020-02-27 Hadyan L. Prihadi , Muhammad F. A. R. Sakti , Getbogi Hikmawan , Freddy P. Zen

The spacetime solution for a black hole, surrounded by an exotic matter field, in Rastall gravity, is calculated in an arbitrary d-dimensional spacetime. After this, we calculate the scalar quasinormal modes of such solution, and study the…

General Relativity and Quantum Cosmology · Physics 2018-06-12 J. P. Morais Graça , Iarley P. Lobo

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

We continue to study the response of black-hole space-times on the presence of additional strong sources of gravity. Restricting ourselves to static and axially symmetric (electro-)vacuum exact solutions of Einstein's equations, we first…

General Relativity and Quantum Cosmology · Physics 2016-08-23 M. Basovník , O. Semerák

Cutting out an infinite tube around $r=0$ formally removes the Schwarzschild singularity, but without a physical mechanism this procedure seems ad hoc and artificial. In this paper we provide justification for such a mechanism by means of…

General Relativity and Quantum Cosmology · Physics 2025-04-01 Jens Boos

Focusing on the special case of generalized Rastall theory, as a subclass of the non-minimal curvature-matter coupling theories in which the field equations are mathematically similar to the Einstein field equations in the presence of…

General Physics · Physics 2019-10-18 H. Moradpour , Y. Heydarzade , C. Corda , A. H. Ziaie , S. Ghaffari

We present a class of new nonsingular black holes in higher dimensional theories of gravity. Assuming a specific form of the stress energy tensor exact analytic solutions of the field equation are generated in general theory of relativity…

General Relativity and Quantum Cosmology · Physics 2023-01-03 Bikash Chandra Paul

We constructed thin-shell wormholes using the well-known "cut and paste" technique for static black holes sourced by an anisotropic fluid within the context of the Rastall gravity. Using the generalized Lanczos equations we explored the…

General Relativity and Quantum Cosmology · Physics 2020-07-14 Iarley P. Lobo , Martin G. Richarte , J. P. Morais Graça , H. Moradpour