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arXiv · 2003.10842

Study of gravastars under $f(\mathbb{T})$ gravity

Amit Das·Shounak Ghosh·Debabrata Deb·Farook Rahaman·Saibal Ray
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Abstract

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 gravastar}, a viable alternative to the black hole. This gravastar has three different regions, viz., (A) Interior core region, (B) Intermediate thin shell, and (C) Exterior spherical region. It is assumed that in the interior region the fluid pressure is equal to a negative matter-energy density providing a constant repulsive force over the spherical thin shell. This shell at the intermediate region is assumed to be formed by a fluid of ultrarelativistic plasma and the pressure, which is directly proportional to the matter-energy density according to Zeldovich's conjecture of stiff fluid~[Zeldovich, Mon. Not. R. Astron. Soc. 160 (1972) 1], does nullify the repulsive force exerted by the interior core region for a stable configuration. On the other hand, the exterior spherical region can be described by the exterior Schwarzschild-de Sitter solution. With all these specifications we have found out a set of exact and singularity-free solutions of the gravastar which presents several physically interesting as well as valid features within the framework of alternative gravity.

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Amit Das, Shounak Ghosh, Debabrata Deb, Farook Rahaman, Saibal Ray. 2020-03-20. Study of gravastars under $f(\mathbb{T})$ gravity. https://doi.org/10.1016/j.nuclphysb.2020.114986

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