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Related papers: Shadow of a Noncommutative Thin-Shell Gravastar

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Viable alternatives to astrophysical black holes include hyper-compact objects without horizon, such as gravastars, boson stars, wormholes and superspinars. The authors have recently shown that typical rapidly-spinning gravastars and boson…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Vitor Cardoso , Paolo Pani , Mariano Cadoni , Marco Cavaglia

We have recently proposed a model for a regular black hole, or an ultra-compact object, that is premised on having maximally negative radial pressure throughout the entirety of the object's interior. This model can be viewed as that of a…

General Relativity and Quantum Cosmology · Physics 2022-01-19 Ram Brustein , A. J. M. Medved , Tamar Simhon

The Ba\~{n}ados, Teitelboim and Zanelli \cite{BTZ1992}, black hole solution is revamped from the Einstein field equations in (2 + 1)-dimensional anti-de Sitter spacetime, in a context of noncommutative geometry \cite{Rahaman(2013)}. In this…

General Relativity and Quantum Cosmology · Physics 2016-12-21 Ayan Banerjee , Sudan Hansraj

In the present work, we have discussed the four dimensional spherically symmetric steller system in the framework of modified $f(T)$ gravity theory with electro-magnetic field. The field equations have been written for two cases, either…

General Relativity and Quantum Cosmology · Physics 2019-07-24 Ujjal Debnath

The recent observations of neutron star mergers have changed our perspective on scalar- tensor theories of gravity, favouring models where gravitational waves travel at the speed of light. In this work we consider a scalar-tensor set-up…

General Relativity and Quantum Cosmology · Physics 2018-08-15 Javier Chagoya , Gianmassimo Tasinato

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

We explore possibility to find out a new model of gravastars in the extended $D$-dimensional Einstein-Maxwell spacetime. The class of solutions as obtained by Mazur and Mottola of a neutral gravastar \cite{Mazur2001,Mazur2004} have been…

General Physics · Physics 2017-03-02 S. Ghosh , Farook Rahaman , B. K. Guha , Saibal Ray

We examine the behavior of non-commutative Schwarzschild black holes in the context of massive gravity. According to the investigation, corresponding to a minimal mass, the black hole can have two horizons, one horizon, or no horizon at…

General Relativity and Quantum Cosmology · Physics 2024-04-17 Piyali Bhar , Dhruba Jyoti Gogoi , Supakchai Ponglertsakul

We develop an extremely general and robust framework that can be adapted to wide classes of generic spherically symmetric thin-shell gravastars. The thin shell (transition layer) will be permitted to move freely in the bulk spacetimes,…

General Relativity and Quantum Cosmology · Physics 2015-12-25 Francisco S. N. Lobo , Prado Martín-Moruno , Nadiezhda Montelongo-García , Matt Visser

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

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

In this article, we are reporting for the first time the existence of gravastar configurations in the framework of K(R,T)-gravity, which can be treated as an alternative to a black hole (Mazur and Mottola). This strengthens how much this…

General Relativity and Quantum Cosmology · Physics 2023-08-22 GRP Teruel , Ksh. Newton Singh , Tanmoy Chowdhury , Farook Rahaman , Monimala Mondal

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

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

We study the shadow and energy emission rate of a spherically symmetric non-commutative black hole in Rastall gravity. Depending on the model parameters, the non-commutative black hole can reduce to the Schwarzschild black hole. Since the…

High Energy Physics - Theory · Physics 2020-05-19 Ali Övgün , İzzet Sakallı , Joel Saavedra , Carlos Leiva

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

Unimodular gravity provides a theoretical framework that allows for non-conservation of energy-momentum, with possible implications for the cosmological constant problem. It is then important to study the predictions of unimodular gravity…

General Relativity and Quantum Cosmology · Physics 2019-09-11 J. A. Astorga-Moreno , Javier Chagoya , J. C. Flores-Urbina , Miguel A. Garcia-Aspeitia

Spherical energy shells in General Relativity tend to collapse due to gravitational effects and/or due to tension effects. Shell stabilization may be achieved by modifying the gravitational properties of the background spacetime. Thus,…

General Relativity and Quantum Cosmology · Physics 2022-08-17 I. Antoniou , D. Kazanas , D. Papadopoulos , L. Perivolaropoulos

Noncommutative geometry may be a starting point to a quantum gravity. We study the influence of the spacetime noncommutative parameter on the strong field gravitational lensing in the noncommutative Schwarzschild black-hole spacetime and…

General Relativity and Quantum Cosmology · Physics 2011-04-22 Chikun Ding , Shuai Kang , Chang-Yong Chen , Songbai Chen , Jiliang Jing

We study gravitational-wave emission from the quasi-circular, extreme mass ratio inspiral of compact objects of mass m0 into massive objects of mass M>>m0 whose external metric is identical to the Schwarzschild metric, except for the…

General Relativity and Quantum Cosmology · Physics 2010-04-14 Paolo Pani , Emanuele Berti , Vitor Cardoso , Yanbei Chen , Richard Norte
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