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arXiv · 2208.01400

Impact of Charge on Gravastars in $f(\mathfrak{R},\mathcal{T}^{2})$ Gravity

M. Sharif·Saba Naz
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Abstract

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 structure involves three distinct regions, i.e., interior, exterior and thin-shell. We analyze these domains of a gravastar for a particular model of this modified theory. In the inner region of a gravastar, the considered equation of state defines that energy density is equal to negative pressure which is the cause of repulsive force on the spherical shell. In the intermediate shell, pressure and energy density are equal and contain ultra-relativistic fluid. The inward-directed gravitational pull of thin-shell counterbalance the force exerted by the inner region of a gravastar allowing the formation of a singularity-free object. The Reissner-Nordstrom metric presents the outer vacuum spherical domain. Moreover, we discuss the impact of the charge on physical attributes of a gravastar such as the equation of state parameter, entropy, proper length and energy. We conclude that singularity-free solutions of charged gravastar are physically consistent in this modified theory.

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M. Sharif, Saba Naz. 2022-08-01. Impact of Charge on Gravastars in $f(\mathfrak{R},\mathcal{T}^{2})$ Gravity. https://doi.org/10.1142/s0217732322500651

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