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Related papers: Gravastars as Nontopological Solitons

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A non-Abelian gauge model with a complex isovector scalar field and a sixth-order self-interaction potential is considered. It is shown that it has a nontopological soliton solution. The features of this soliton include a monopole-like core…

High Energy Physics - Theory · Physics 2025-06-26 A. Yu. Loginov

We present a class of exact solutions of Einstein's gravitational field equations describing spherically symmetric and static anisotropic stellar type configurations. The solutions are obtained by assuming a particular form of the…

General Relativity and Quantum Cosmology · Physics 2017-10-04 T. Harko , M. K. Mak

We find a new non BPS solution in $N=2$ $D=4$ gauged supergravity coupled to $U(1)$ gauge fields and matter. It consists in a closed universe with two extremal black holes of equal size, surrounding two singularities. They have opposite…

High Energy Physics - Theory · Physics 2021-12-08 Sergio Luigi Cacciatori , Davide Astesiano

We study static, spherically symmetric, self-gravitating systems minimally coupled to a scalar field with U(1) gauge symmetry: charged boson stars. We find numerical solutions to the EinsteinMaxwell equations coupled to the relativistic…

High Energy Astrophysical Phenomena · Physics 2013-08-05 Daniela Pugliese , Hernando Quevedo , Jorge A. Rueda H. , Remo Ruffini

In this work, we present a detailed investigation of gravastars within the framework of scalar-tensor theories, emphasizing both the background and perturbed levels for trivial and non trivial scalar field. We derive and analyze the…

General Relativity and Quantum Cosmology · Physics 2025-04-23 Hamza Boumaza

We study spherically symmetric static spacetimes generally filled with an anisotropic fluid in the nonrelativistic general covariant theory of gravity. In particular, we find that the vacuum solutions are not unique, and can be expressed in…

High Energy Physics - Theory · Physics 2011-01-27 Jared Greenwald , V. H. Satheeshkumar , Anzhong Wang

We investigate the physical properties of quark stars with two different equations of state in generalized hybrid metric-Palatini gravity. This theory corresponds to a bi-scalar gravitational theory in which there are two…

General Relativity and Quantum Cosmology · Physics 2024-10-15 R. Aliannejadi , Z. Haghani

Quadratic scale-invariant gravity non minimally coupled to a scalar field provides a competitive model for inflation, characterized by the transition from an unstable to a stable fixed point, both characterized by constant scalar field…

General Relativity and Quantum Cosmology · Physics 2023-01-27 Simon Boudet , Massimiliano Rinaldi , Samuele Marco Silveravalle

In the present paper we propose a stellar model under the $f(\mathbb{T})$ gravity following the conjecture of Mazur-Mottola~[Report number: LA-UR-01-5067 (2001); Proc. Natl. Acad. Sci. USA 101 (2004) 9545] known in literature as {\it…

General Relativity and Quantum Cosmology · Physics 2020-03-25 Amit Das , Shounak Ghosh , Debabrata Deb , Farook Rahaman , Saibal Ray

This manuscript examines viability and stability of anisotropic compact objects in the framework of $f(Q,L_m)$ gravity ($Q$ is the non-metricity and $L_m$ is the matter Lagrangian). We assume a particular functional form of this theory to…

General Relativity and Quantum Cosmology · Physics 2026-05-05 M. Sharif , M. Zeeshan Gul , Adeeba Arooj

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

In this paper we consider the Dvali and G\'omez assumption that the end state of a gravitational collapse is a Bose-Einstein condensate of gravitons. We then construct the two Gross-Pitaevskii equations for a static and spherically…

General Relativity and Quantum Cosmology · Physics 2018-05-02 Francesc Cunillera , Cristiano Germani

We study boson stars in a theory of complex scalar field coupled to Einstein gravity with the potential: $V(|\Phi|) := m^{2} |\Phi|^2 +2 \lambda |\Phi|$ (where $m^2$ and $\lambda$ are positive constant parameters). This could be considered…

High Energy Physics - Theory · Physics 2016-05-24 Sanjeev Kumar , Usha Kulshreshtha , Daya Shankar Kulshreshtha

Two distinct non-singular interior models that describe anisotropic spherical configurations are presented in this work. We develop the Einstein field equations and the associated mass function in accordance with a static spherical…

General Relativity and Quantum Cosmology · Physics 2025-10-10 M. Sharif , Tayyab Naseer , Hira Shadab

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

In the present investigation compact stellar models are dealt with in the framework of the modified gravity theory, specifically of $f(\mathbb{T},\mathcal{T})$ type. We have considered that the compact objects are following a spherically…

General Relativity and Quantum Cosmology · Physics 2021-06-29 Ines G. Salako , Chayan Ranjit , M. Khlopov , Saibal Ray , Utpal Mukhopadhyay

We study axially symmetric static solitons of O(3) nonlinear $\sigma$ model coupled to (2+1)-dimensional anti-de Sitter gravity. The obtained solutions are not self-dual under static metric. The usual regular topological lump solution…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Yoonbai Kim , Sei-Hoon Moon

In theories of gravitation in which dimensional parameters are dynamically induced, one can have non - topological - soliton solutions. This article reviews related topics connected with such solutions. The existence of such solutions in…

General Relativity and Quantum Cosmology · Physics 2009-09-25 Daksh Lohia

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 study relativistic stars in Hordenski theories that evade the gravitational wave constraints and exhibit the Vainshtein mechanism, focusing on a model based on the cubic Galileon Lagrangian. We derive the scalar field profile for static…

General Relativity and Quantum Cosmology · Physics 2020-01-15 Hiromu Ogawa , Tsutomu Kobayashi , Kazuya Koyama