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arXiv · 2108.06989

Stable and self consistent charged gravastar model within the framework of $f(R,\,T)$ gravity

Piyali Bhar·Pramit Rej
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Abstract

In this work, we discuss the configuration of a gravastar (gravitational vacuum stars) in the context of $f(R, \,T )$ gravity by employing the Mazur-Mottola conjecture [P. Mazur and E. Mottola, Report No. LA-UR-01-5067; P. Mazur and E. Mottola, Proc. Natl. Acad. Sci. USA $101$, $9545$ ($2004$)]. Gravastar is conceptually a substitute for a black hole theory as available in literature and it has three regions with different equation of states. By assuming that the gravastar geometry admits conformal killing vector, the Einstein-Maxwell field equations have been solved in different regions of gravastar by taking a specific equation of state as proposed by Mazur and Mottola. We match our interior spacetime to the exterior spherical region which is completely vacuum and described by Reissner-Nordstr\"{o}m geometry. For a particular choice of $f(R,\,T)$ as $f(R, \,T )=R+2\gamma T$, here we analyze various physical properties of the thin shell and also presented our results graphically for these properties. The stability analysis of our present model is also studied by introducing a new parameter $\eta$ and we explored the stability regions. Our proposed gravastar model in presence of charge might be treated as a successful stable alternative of the charged black hole in the context of this gravity.

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Piyali Bhar, Pramit Rej. 2021-08-16. Stable and self consistent charged gravastar model within the framework of $f(R,\,T)$ gravity. https://doi.org/10.1140/epjc%2Fs10052-021-09548-0

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