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Gravastar Solutions with Continuous Pressures and Equation of State

A. DeBenedictis·D. Horvat·S. Ilijic·S. Kloster·K. S. Viswanathan
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Abstract

We study the gravitational vacuum star (gravastar) configuration as proposed by other authors in a model where the interior de Sitter spacetime segment is continuously extended to the exterior Schwarzschild spacetime. The multilayered structure in previous papers is replaced by a continuous stress-energy tensor at the price of introducing anisotropy in the (fluid) model of the gravastar. Either with an ansatz for the equation of state connecting the radial $p_r$ and tangential $p_t$ pressure or with a calculated equation of state with non-homogeneous energy/fluid density, solutions are obtained which in all aspects satisfy the conditions expected for an anisotropic gravastar. Certain energy conditions have been shown to be obeyed and a polytropic equation of state has been derived. Stability of the solution with respect to possible axial perturbation is shown to hold.

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A. DeBenedictis, D. Horvat, S. Ilijic, S. Kloster, K. S. Viswanathan. 2007-06-19. Gravastar Solutions with Continuous Pressures and Equation of State. https://doi.org/10.1088/0264-9381%2F23%2F7%2F007

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