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arXiv · 0807.2051

Electrically charged gravastar configurations

Dubravko Horvat·Sasa Ilijic·Anja Marunovic
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Abstract

The notion of a compact object immune to the horizon problem and comprising an anisotropic inhomogeneous fluid with a specific radial pressure behavior, i.e. the gravastar, is extended by introducing an electrically charged component. Einstein-Maxwell field equations are solved in the asymptotically de Sitter interior where a source of the electric field is coupled to the fluid energy density. Two different solutions which satisfy the dominant energy condition are given: one is the delta-shell model for which the analysis is carried out within Israel's thin shell formalism, the other approach - the continuous profile model - is solved numerically and the interior solutions have been (smoothly) joined with the Reissner-Nordstrom exterior. The effect of electric charge is considered, and the equation of state, the speed of sound and the surface redshift are calculated for both models.

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Dubravko Horvat, Sasa Ilijic, Anja Marunovic. 2008-12-02. Electrically charged gravastar configurations. https://doi.org/10.1088/0264-9381%2F26%2F2%2F025003

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