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Related papers: Formation of Cylindrical Gravastars in Modified Gr…

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We consider f(R,T) modified theory of gravity, in which the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar and the trace of the energy-momentum tensor of the matter, in order to investigate the dark-matter…

General Relativity and Quantum Cosmology · Physics 2016-11-02 Raziyeh Zaregonbadi , Mehrdad Farhoudi , Nematollah Riazi

We study wormhole solutions in the framework of f (R,T) gravity where R is the scalar curvature, and T is the trace of the stress-energy tensor of the matter. We have obtained the shape function of the wormhole by specifying an equation of…

General Relativity and Quantum Cosmology · Physics 2014-01-30 Tahereh Azizi

We construct a broad family of thin-shell wormholes with circular symmetry in (2+1)-dimensional F(R) theories of gravity, with constant scalar curvature R. We study the stability of the static configurations under perturbations preserving…

General Relativity and Quantum Cosmology · Physics 2021-08-05 Cecilia Bejarano , Ernesto F. Eiroa , Griselda Figueroa-Aguirre

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

Dynamical models of prototype gravastars were constructed in order to study their stability. The models are the Visser-Wiltshire three-layer gravastars, in which an infinitely thin spherical shell of stiff fluid divides the whole spacetime…

General Relativity and Quantum Cosmology · Physics 2011-03-28 P. Rocha , A. Y. Miguelote , R. Chan , M. F. da Silva , N. O. Santos , Anzhong Wang

In this work we propose the modelling of static wormholes within the $f(R,T)$ extended theory of gravity perspective. We present some models of wormholes, which are constructed from different hypothesis for their matter content, i.e.,…

General Relativity and Quantum Cosmology · Physics 2017-09-06 P. H. R. S. Moraes , P. K. Sahoo

The gravastar model, which postulates a strongly correlated thin shell of anisotropic matter surrounding a region of anti-de Sitter space, has been proposed as an alternative to black holes. We discuss constraints that present-day…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Avery E. Broderick , Ramesh Narayan

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 study the gravitational vacuum star (gravastar) configuration as proposed by other authors in a model where the interior de Sitter spacetime segment is continuously extended to the exterior Schwarzschild spacetime. The multilayered…

General Relativity and Quantum Cosmology · Physics 2007-06-19 A. DeBenedictis , D. Horvat , S. Ilijic , S. Kloster , K. S. Viswanathan

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

We combine the ideas of a Weyl scaling invariant dark energy action, which eliminates black hole horizons, with the ``gravastar'' idea of a jump in the hole interior from a normal matter equation of state to an equation of state where…

General Relativity and Quantum Cosmology · Physics 2023-02-22 Stephen L. Adler

There is a host of alternative theories of gravitation in the literature, among them the $f(R,T)$ recently elaborated by Harko and collaborators. In these theories the $R$ and $T$ are respectively the Ricci scalar and the trace of the…

General Relativity and Quantum Cosmology · Physics 2016-07-27 M. E. S. Alves , P. H. R. S. Moraes , J. C. N. de Araujo , M. Malheiro

The basic objective of this investigation is to explore the impact of a novel gravitational modification, specifically, the $f(\mathcal{G}, \mathbf{T}^2)$ (where $\mathbf{T}^2 \equiv T_{\alpha\beta}T^{\alpha\beta}$, $T^{\alpha\beta}$…

General Relativity and Quantum Cosmology · Physics 2022-04-12 Z. Yousaf , M. Z. Bhatti , S. Khan , P. K. Sahoo

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

In this paper, we evaluate traversable wormhole solutions through Karmarkar condition in $f(R,T)$ theory, where $T$ is the trace of the energy-momentum tensor and $R$ represents the Ricci scalar. We develop a wormhole shape function for the…

General Relativity and Quantum Cosmology · Physics 2023-03-06 M. Sharif , Arooj Fatima

A class of $f(R, T)$ theories extends the Einstein-Hilbert action by incorporating a general function of $R$ and $T$, the Ricci scalar and the trace of the ordinary energy-momentum tensor $T_{\mu\nu}$, respectively, thereby introducing a…

General Relativity and Quantum Cosmology · Physics 2025-07-30 Yaghoub Heydarzade , Maryam Ranjbar

In this paper we investigate the gravitational vacuum stars which called gravastars in the non-minimally coupled models with electromagnetic and gravitational fields. We consider two non-minimal models and find the corresponding spherically…

General Relativity and Quantum Cosmology · Physics 2021-11-18 Özcan Sert , Muzaffer Adak

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

We study the structure and stability of traversable wormholes built as (spherically symmetric) thin shells in the context of Palatini $f(\mathcal{R})$ gravity. Using a suitable junction formalism for these theories we find that the…

General Relativity and Quantum Cosmology · Physics 2020-11-11 Francisco S. N. Lobo , Gonzalo J. Olmo , Emanuele Orazi , Diego Rubiera-Garcia , Azmat Rustam

In this article, we consider spherical thin shells of matter surrounding black holes in F(R) theories of gravity. We study the stability of the static configurations under perturbations that conserve the symmetry. In particular, we analyze…

General Relativity and Quantum Cosmology · Physics 2020-07-22 Ernesto F. Eiroa , Griselda Figueroa-Aguirre