Related papers: Thin-shell gravastar model in a BTZ geometry with …
This study analyzes the physical features of a gravastar within the $f(\mathcal{Q}, \mathbb{T})$ gravity framework, where $\mathcal{Q}$ is the non-metricity scalar and $\mathbb{T}$ is the trace of the energy-momentum tensor. Gravastars…
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…
Regular black holes and horizonless black-hole mimickers offer mathematically consistent alternatives to address the challenges posed by standard black holes. However, the formation mechanism of these alternative objects is still largely…
In the present work, we have discussed the four dimensional spherically symmetric steller system in the framework of modified $f(T)$ gravity theory with electro-magnetic field. The field equations have been written for two cases, either…
Gravastars have been considered as a feasible alternative to black holes in the past couple of decades. Stable models of gravastar have been studied in many of the alternative gravity theories besides standard General Relativity (GR). The…
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…
This paper studies the influence of charge on a compact stellar structure also regarded as vacuum condensate star in the background of $f(\mathfrak{R},\mathcal{T}^{2})$ gravity. This object is considered the alternate of black hole whose…
We study thin shells of matter in (2+1)-dimensional F(R) theories of gravity with constant scalar curvature R. We consider a wide class of spacetimes with circular symmetry, in which a thin shell joins an inner region with an outer one. We…
This paper investigates the influence of charge on physical features of gravastars in the framework of energy-momentum squared gravity. A gravastar is an alternate model to a black hole that comprises of three distinct regions, namely the…
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…
Spherical energy shells in General Relativity tend to collapse due to gravitational effects and/or due to tension effects. Shell stabilization may be achieved by modifying the gravitational properties of the background spacetime. Thus,…
The thermodynamic equilibrium states of a static thin ring shell in a (2+1)-dimensional spacetime with a negative cosmological constant are analyzed. Inside the ring, the spacetime is pure anti-de Sitter (AdS), whereas outside it is a…
We study the dynamical and thermodynamical stability of thin shells in (2+1)-dimensional spacetimes composed of an inner anti-de Sitter (AdS) region and an outer region described by a charged Ba\~nados--Teitelboim--Zanelli (BTZ) spacetime,…
In this paper we consider a BTZ black hole with minimum length which has been introduced through the probability density of the ground state of the hydrogen atom. We analyzed the effect of the minimum length by calculating the thermodynamic…
In this paper, we are interested to explore stable configurations of $d$-dimensional gravastars constructed from the interior $d$-dimensional de Sitter and exterior $d$-dimensional Schwarzschild/Reissner-Nordstr\"om (de Sitter) black holes…
In this paper, we construct thin-shell wormholes in (2+1)-dimensions from noncommutative BTZ black hole by applying the cut-and-paste procedure implemented by Visser. We calculate the surface stresses localized at the wormhole throat by…
In case of spherical symmetry, the assumptions of finite-time formation of a trapped region and regularity of its boundary --- the apparent horizon --- are sufficient to identify the form of the metric and energy-momentum tensor in its…
We propose a class of models, in which stable gravastar with large surface redshift becomes a solution. In recent decades, gravastars have become a plausible substitute for black holes. Researchers have explored stable gravastar models in…
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…
In this paper, we investigate a new model of $(2+1)-$dimensional ($3D$) gravitational vacuum stars (gravastars) with an isotropic matter distribution anti-de Sitter (AdS) spacetime in the context of massive gravity. For this purpose, we…