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Related papers: Slowly rotating gravastars

200 papers

We construct a gravastar configuration within the Shtanov-Sahni (SS) braneworld scenario, characterized by a timelike extra dimension and negative brane tension. Unlike classical black holes, which inevitably culminate in central curvature…

General Relativity and Quantum Cosmology · Physics 2026-03-25 Shounak Ghosh , Rikpratik Sengupta , Kazuharu Bamba

We study black hole solutions of Einstein gravity coupled to a specific global symmetry breaking Goldstone model described by an O(3) isovector scalar field in four spacetime dimensions. Our configurations are static and spherically…

General Relativity and Quantum Cosmology · Physics 2011-09-07 Eugen Radu , Ya. Shnir , D. H. Tchrakian

In general, the field equation of $f(R)$ gravitational theory is very intricate, and therefore, it is not an easy task to derive analytical solutions. We consider rotating black hole spacetime four-dimensional in the $f(R)$ gravitational…

General Relativity and Quantum Cosmology · Physics 2023-06-14 G. L. N. Nashed , Shin'ichi Nojiri

We derive the gravitational waveform and gravitational-wave energy flux generated by a binary star system of compact objects (neutron stars or black holes), accurate through second post-Newtonian order ($O[(v/c)^4] \sim O[(Gm/rc^2)^2]$)…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Clifford M. Will , Alan G. Wiseman

Charged, rotating black hole solutions of Einstein's gravitational equations are investigated in the presence of a cosmological constant. A pair of wave equations governing the electromagnetic and gravitational perturbations are derived.

General Relativity and Quantum Cosmology · Physics 2007-05-23 Zoltán Perjés

We investigate the structure of strange dwarfs, modeled as hybrid compact stars composed of a self bound strange quark matter core surrounded by a white dwarf like crust, within a fully relativistic framework. Static configurations are…

Solar and Stellar Astrophysics · Physics 2026-02-06 Edson Otoniel , José D. V. Arbañil , Geanderson A. Carvalho , Fridolin Weber

Using the effective field theory of quantum gravity at second order in curvature, we calculate quantum corrections to the metric of gravastars and the closely related dark energy stars. We find that the quantum corrections in the exterior…

General Relativity and Quantum Cosmology · Physics 2025-03-12 Italo Perrucci , Folkert Kuipers , Roberto Casadio

We prove the linear stability of slowly rotating Kerr black holes as solutions of the Einstein vacuum equation: linearized perturbations of a Kerr metric decay at an inverse polynomial rate to a linearized Kerr metric plus a pure gauge…

Analysis of PDEs · Mathematics 2019-07-17 Dietrich Häfner , Peter Hintz , András Vasy

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

We show that in four or more spacetime dimensions, the Einstein equations for gravitational perturbations of maximally symmetric vacuum black holes can be reduced to a single 2nd-order wave equation in a two-dimensional static spacetime for…

High Energy Physics - Theory · Physics 2009-11-10 Hideo Kodama , Akihiro Ishibashi

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

The recent simultaneous detection of gravitational waves and a gamma ray burst from a neutron star merger significantly shrank the space of viable scalar-tensor theories by demanding that the speed of gravity is equal to that of light. The…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-06 Marco Crisostomi , Kazuya Koyama

Using graphs plotted from the Mathematica notebooks posted with our paper ``Dynamical Gravastars'', we show that a dynamical gravastar has no hard surface, and that a second light sphere resides in the deep interior where there is maximum…

General Relativity and Quantum Cosmology · Physics 2024-02-13 Stephen L. Adler

We apply the recent results in Loop Quantum Cosmology and in the resolution of Black Hole singularity to the gravitational collapse of a star. We study the dynamic of the space time in the interior of the Schwarzschild radius. In particular…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Leonardo Modesto

In this work, we have considered the spherically symmetric stellar system in the contexts of Rastall-Rainbow gravity theory in presence of isotropic fluid source with electromagnetic field. The Einstein-Maxwell's field equations have been…

General Physics · Physics 2019-09-04 Ujjal Debnath

In recent days gravastar has been a very lucrative alternative to black holes, as it does not suffer from the singularity problem as well and it is based on sound physical grounds. Modified Symmetric teleparallel equivalent of gravity also…

General Relativity and Quantum Cosmology · Physics 2024-03-05 Debasmita Mohanty , Sayantan Ghosh , P. K. Sahoo

Weak field approximate solutions in the Lambda-->0 limit of a model of de Sitter gravity have been presented in the static and spherically symmetric case. Although the model looks different from general relativity, among those solutions,…

General Relativity and Quantum Cosmology · Physics 2013-02-19 Jia-An Lu , Chao-Guang Huang

The occurrence of a spacetime singularity indicates the breakdown of Einstein gravitation theory in these extreme regimes. We consider here the singularity issue and various black hole paradoxes at classical and quantum levels. It is…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Rituparno Goswami , Pankaj S. Joshi

This work is devoted to study the analytical and regular solutions of a particular self-gravitating object (i.e., gravastar) in a particular theory of gravity. We derive the corresponding field equations in the presence of effective energy…

General Relativity and Quantum Cosmology · Physics 2021-08-30 Z. Yousaf , M. Z. Bhatti , H. Asad

We review our recent work on linear stability for scalar perturbations of Kerr spacetimes, that is to say, boundedness and decay properties for solutions of the scalar wave equation \Box_g{\psi} = 0 on Kerr exterior backgrounds. We begin…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Mihalis Dafermos , Igor Rodnianski