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arXiv · 0708.4196

A universal constraint between charge and rotation rate for degenerate black holes surrounded by matter

Marcus Ansorg·Herbert Pfister
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Abstract

We consider stationary, axially and equatorially symmetric systems consisting of a central rotating and charged degenerate black hole and surrounding matter. We show that $a^2+Q^2=M^2$ always holds provided that a continuous sequence of spacetimes can be identified, leading from the Kerr-Newman solution in electrovacuum to the solution in question. The quantity $a=J/M$ is the black hole's intrinsic angular momentum per unit mass, $Q$ its electric charge and $M$ the well known black hole mass parameter introduced by Christodoulou and Ruffini.

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Marcus Ansorg, Herbert Pfister. 2008-01-24. A universal constraint between charge and rotation rate for degenerate black holes surrounded by matter. https://doi.org/10.1088/0264-9381%2F25%2F3%2F035009

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