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arXiv · 2301.02914

Gravastar-like black hole solutions in $q$-theory

M. Selch·J. Miller·M. A. Zubkov
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Abstract

We present a stationary spherically symmetric solution of the Einstein equations, with a source generated by a scalar field of $q$-theory. In this theory Riemannian gravity, as described by the Einstein - Hilbert action, is coupled to a three - form field that describes the dynamical vacuum. Formally it behaves like a matter field with its own stress - energy tensor, equivalent to a scalar field minimally coupled to gravity. The asymptotically flat solutions obtained to the field equations represent black holes. For a sufficiently large horizon radius the energy density is localized within a thin spherical shell situated just outside of the horizon, analogous to a gravastar. The resulting solutions to the field equations, which admit this class of configurations, satisfy existence conditions that stem from the Black Hole no - hair theorem, thanks to the presence of a region in space in which the energy density is negative.

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M. Selch, J. Miller, M. A. Zubkov. 2023-01-07. Gravastar-like black hole solutions in $q$-theory. https://doi.org/10.1088/1361-6382%2Face14b

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