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arXiv · 2003.04893

Stability of Gravastars with Exterior Regular Black Holes

M. Sharif·Faisal Javed
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Abstract

This paper examines the stability of thin-shell gravastars in the context of regular spacetimes (Bardeen and Bardeen-de Sitter black holes). We apply cut and paste approach to construct gravastars through the matching of interior non-singular de Sitter geometry with exterior regular black hole. This model contains three regions, i.e., interior, thin-shell and exterior. The interior and exterior regions are connected at thin-shell. We investigate physical viability of the developed model by the energy conditions and explore its stability by using radial perturbation about the equilibrium shell radius. It is found that thin-shell gravastars show large stable regions for the Bardeen-de Sitter black hole as compared to the Bardeen black hole. It is concluded that stable regions exist near the formation of expected event horizon.

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M. Sharif, Faisal Javed. 2020-03-10. Stability of Gravastars with Exterior Regular Black Holes. https://doi.org/10.1016/j.aop.2020.168124

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