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arXiv · 1412.8304

Quasi-stationary solutions of self-gravitating scalar fields around black holes

Nicolas Sanchis-Gual·Juan Carlos Degollado·Pedro J. Montero·José A. Font
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Abstract

Recent perturbative studies have shown the existence of long-lived, quasi-stationary configurations of scalar fields around black holes. In particular, such configurations have been found to survive for cosmological timescales, which is a requirement for viable dark matter halo models in galaxies based on such type of structures. In this paper we perform a series of numerical relativity simulations of dynamical non-rotating black holes surrounded by self-gravitating scalar fields. We solve numerically the coupled system of equations formed by the Einstein and the Klein-Gordon equations under the assumption of spherical symmetry using spherical coordinates. Our results confirm the existence of oscillating, long-lived, self-gravitating scalar fields configurations around non-rotating black holes in highly dynamical spacetimes with a rich scalar field environment. Our numerical simulations are long-term stable and allow for the extraction of the resonant frequencies to make a direct comparison with results obtained in the linearized regime. A byproduct of our simulations is the existence of a degeneracy in plausible long-lived solutions of Einstein equations that would induce the same motion of test particles, either with or without the existence of quasi-bound states.

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Nicolas Sanchis-Gual, Juan Carlos Degollado, Pedro J. Montero, José A. Font. 2014-12-29. Quasi-stationary solutions of self-gravitating scalar fields around black holes. https://arxiv.org/abs/1412.8304

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