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Related papers: Gravastars in $f(R,G)$ Gravity

200 papers

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

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

We investigate a coupled system consisting of a complex scalar field, a U(1) gauge field, a complex Higgs scalar field, and Einstein gravity. We present nontopological soliton star solutions in which the interior geometry is described by…

High Energy Physics - Theory · Physics 2024-09-25 Tatsuya Ogawa , Hideki Ishihara

Gravastars have been considered as a serious alternative to black holes in the past couple of decades. Stable models of gravastar have been constructed in many of the alternate gravity models besides standard General Relativity (GR). The…

General Relativity and Quantum Cosmology · Physics 2020-07-15 Rikpratik Sengupta , Shounak Ghosh , Saibal Ray , B. Mishra , S. K. Tripathy

A gravastar comprises three distinct sections: the interior zone, the middle shell, and its outer region. By considering a specific extended teleparallel gravity model that incorporates conformal Killing vectors and provides the field…

General Relativity and Quantum Cosmology · Physics 2024-04-30 G. Mustafa , Faisal Javed , Arfa Waseem , S. K. Maurya , Ghulam Fatima

This paper develops a new solution of gravitational vacuum star in the background of charged Kiselev black holes as an exterior manifold. We explore physical features and stability of thin-shell gravastars with radial perturbation. The…

General Relativity and Quantum Cosmology · Physics 2021-02-17 M. Sharif , Faisal Javed

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 notion of a compact object immune to the horizon problem and comprising an anisotropic inhomogeneous fluid with a specific radial pressure behavior, i.e. the gravastar, is extended by introducing an electrically charged component.…

General Relativity and Quantum Cosmology · Physics 2009-01-16 Dubravko Horvat , Sasa Ilijic , Anja Marunovic

In this paper we construct a charged thin-shell gravastar model within the context of noncommutative geometry. To do so, we choose the interior of the nonsingular de Sitter spacetime with an exterior charged noncommutative solution by…

General Relativity and Quantum Cosmology · Physics 2017-08-24 Ali Övgün , Ayan Banerjee , Kimet Jusufi

As a preparation for the dynamical investigations, this paper begins with a short review of the three-layer gravastar model with distinguished attention to the structure of the pertinent parameter space of gravastars in equilibrium. Then…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Merse E. Gáspár , István Rácz

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

In this work we examine the internal structure of compact stars within an extended gravitational framework described by the function $f(\mathcal{R},\mathcal{G},\mathcal{T})$. Throughout this work, the quantity $\mathcal{R}$ refers to the…

General Relativity and Quantum Cosmology · Physics 2025-11-25 G. G. L. Nashed

In this paper we attempt to construct a regular gravastar model using the UV corrected framework of Loop Quantum Cosmology. We find that a stable gravastar model can be constructed with a number of unique features: (i) no thin shell…

General Relativity and Quantum Cosmology · Physics 2026-02-06 Shounak Ghosh , Rikpratik Sengupta , Mehedi Kalam

Within the paradigm of non-perturbative Einstein gravity we study continuous curvature manifolds which possess de Sitter interiors and Kerr exteriors. These manifolds could represent the spacetime of rotating gravastars or other similar…

General Relativity and Quantum Cosmology · Physics 2025-03-27 Sasa Ilijic , Andrew DeBenedictis

We consider a gravastar model made of anisotropic dark energy with an infinitely thin spherical shell of a perfect fluid with the equation of state $p = (1-\gamma)\sigma$ with an external de Sitter-Schwarzschild region. It is found that in…

General Relativity and Quantum Cosmology · Physics 2015-03-17 C. F. C. Brandt , R. Chan , M. F. A. da Silva , P. Rocha

In the current letter, we study isotropic static spherically symmetric gravastars without charge under the framework of braneworld gravity (dimensionally reduced RS-II braneworld with positive brane tension) using the metric potential of…

General Relativity and Quantum Cosmology · Physics 2022-04-07 Oleksii Sokoliuk , Alexander Baransky , P. K. Sahoo

In this work, we find exact gravastar solutions in the context of noncommutative geometry, and explore their physical properties and characteristics. The energy density of these geometries is a smeared and particle-like gravitational…

General Relativity and Quantum Cosmology · Physics 2013-12-16 Francisco S. N. Lobo , Remo Garattini

Dynamical models of prototype gravastars made of anisotropic dark energy are constructed, in which an infinitely thin spherical shell of a perfect fluid with the equation of state $p = (1-\gamma)\sigma$ divides the whole spacetime into two…

General Relativity and Quantum Cosmology · Physics 2011-07-21 R. Chan , M. F. A. da Silva , P. Rocha

Here we propose the extended modified gravity theory named as $f(R,G,\mathcal{T})$ gravity where $R$ is the Ricci scalar, $G$ is the Gauss-Bonnet invariant and $\mathcal{T}$ is the trace of the stress-energy tensor. We derive the…

General Relativity and Quantum Cosmology · Physics 2020-12-02 Ujjal Debnath

We propose a new model of a gravastar in (2+1) anti-de Sitter space-time. This new three dimensional configuration has three different regions with different equations of state: [I] Interior: 0 \leq r < r_1, \rho = -p ; [II] Shell: r_1 \leq…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Farook Rahaman , Saibal Ray , A. A. Usmani , Safiqul Islam