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Related papers: Study of gravastars under $f(\mathbb{T})$ gravity

200 papers

We introduce two classes of spherically symmetric spacetimes having a thin shell of matter, in non-quadratic F(R) theories of gravity with non-constant scalar curvature R. In the first, the thin shell joins an inner region with an outer…

General Relativity and Quantum Cosmology · Physics 2020-10-07 Ernesto F. Eiroa , Griselda Figueroa-Aguirre

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

We consider static spherically symmetric self-gravitating configurations of the perfect fluid within the framework of the torsion-based extended theory of gravity. In particular, we use the covariant formulation of $f(T)$ gravity with $f(T)…

General Relativity and Quantum Cosmology · Physics 2018-10-03 Sasa Ilijic , Marko Sossich

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

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

The low energy effective theory of gravity comprises two elements of quantum theory joined to classical general relativity. The first is the quantum conformal anomaly, which is responsible for macroscopic correlations on light cones and a…

General Relativity and Quantum Cosmology · Physics 2025-02-05 Emil Mottola

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 study the dipolar magnetic field configuration and present solutions of Maxwell equations in the internal background spacetime of a a slowly rotating gravastar. The shell of gravastar where magnetic field penetrated is modeled as sphere…

General Relativity and Quantum Cosmology · Physics 2010-04-20 B. V. Turimov , B. J. Ahmedov , A. A. Abdujabbarov

Mazharimousavi and Halilsoy [1] recently proposed wormhole solutions in $f(R)$-gravity that satisfy energy conditions but are unstable. We show here that stability could still be achieved for thin-shell wormholes obtained by gluing the…

General Relativity and Quantum Cosmology · Physics 2019-02-20 Alina Khaybullina , Gulira Tuleganova

The properties of a star with constant positive energy density inside (as for the Schwarzschild interior geometry) and a negative pressure are investigated, using a static conformally flat spacetime. Because of the negative pressure, the…

General Relativity and Quantum Cosmology · Physics 2025-04-08 Hristu Culetu

In this paper, we investigate the thermodynamic behavior of a horizonless compact object within the framework of Rastall-Rainbow (RR) gravity. Working with local shell thermodynamics for gravastar and an exterior fiducial temperature, we…

General Relativity and Quantum Cosmology · Physics 2025-12-16 Sareh Eslamzadeh , Saheb Soroushfar

We have proposed a model geometry for the interior of a regular black hole mimicker, the frozen star, whose most startling feature is that each spherical shell in its interior is a surface of infinite redshift. The geometry is a solution of…

General Relativity and Quantum Cosmology · Physics 2023-01-25 Ram Brustein , A. J. M. Medved , Tom Shindelman , Tamar Simhon

We derive regular black-hole solutions, including the Hayward metric, from four-dimensional action principles involving vector fields in addition to the metric. These black holes possess additional hair associated with the vector fields,…

General Relativity and Quantum Cosmology · Physics 2026-03-30 Astrid Eichhorn , Pedro G. S. Fernandes

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

In this paper, we investigate spherically symmetric perfect fluid gravitational collapse in metric $f(R)$ gravity. We take non-static spherically symmetric metric in the interior region and static spherically symmetric metric in the…

General Relativity and Quantum Cosmology · Physics 2011-01-17 M. Sharif , H. Rizwana Kausar

A static, spherically symmetric spacetime with negative pressures is conjectured inside a star. The gravitational field is repulsive and so a central singularity is avoided. The positive energy density and the pressures of the imperfect…

General Relativity and Quantum Cosmology · Physics 2020-05-05 Hristu Culetu

A new solution for the endpoint of gravitational collapse is proposed. By extending the concept of Bose-Einstein condensation to gravitational systems, a cold, compact object with an interior de Sitter condensate phase and an exterior…

General Relativity and Quantum Cosmology · Physics 2023-02-16 Pawel O. Mazur , Emil Mottola

This manuscript aims to establish the gravitational junction conditions(JCs) for the $f(\mathcal{G},~T)$ gravity. In this gravitational theory, $f$ is an arbitrary function of Gauss-Bonnet invariant $\mathcal{G}$ and the trace of the…

General Relativity and Quantum Cosmology · Physics 2022-07-14 M. Z. Bhatti , Z. Yousaf , M. Yousaf

We systematically study spherically symmetric static spacetimes filled with a fluid in the Horava-Lifshitz theory of gravity with the projectability condition, but without the detailed balance. We establish that when the spacetime is…

High Energy Physics - Theory · Physics 2010-05-12 Jared Greenwald , Antonios Papazoglou , Anzhong Wang

The ergoregion instability is known to affect very compact objects that rotate very rapidly and do not possess a horizon. We present here a detailed analysis on the relevance of the ergoregion instability for the viability of gravastars.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Cecilia B. M. H. Chirenti , Luciano Rezzolla