Bose-Einstein Condensates in Charged Black-Hole Spacetimes

TL;DR

This paper investigates the properties of Bose-Einstein condensates modeled as scalar fields around various charged black-hole spacetimes, exploring their potential as dark matter clouds and their use in distinguishing black hole types.

Contribution

It introduces a model of scalar field Bose-Einstein condensates in charged black-hole spacetimes and analyzes their characteristics and observational signatures.

Findings

Existence of quasi-bound scalar field states around charged black holes.

Estimated size and energy of dark matter-like clouds near supermassive black holes.

Potential to differentiate black hole types based on condensate features.

Abstract

We analyze Bose-Einstein condensates on three types of spherically symmetric and static charged black-hole spacetimes: The Reissner-Nordstr\"om spacetime, Hoffmann's Born-Infeld black-hole spacetime, and the regular Ay\'on-Beato-Garc\'ia spacetime. The Bose-Einstein condensate is modeled in terms of a massive scalar field that satisfies a Klein-Gordon equation with a self-interaction term. The scalar field is assumed to be uncharged and not self-gravitating. If the mass parameter of the scalar field is chosen sufficiently small, there are quasi-bound states of the scalar field that may be interpreted as dark matter clouds. We estimate the size and the total energy of such clouds around charged supermassive black holes and we investigate if their observable features can be used for discriminating between the different types of charged black holes.