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arXiv · 1502.02930

On the black hole limit of rotating discs of charged dust

Martin Breithaupt·Yu-Chun Liu·Reinhard Meinel·Stefan Palenta
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Abstract

Investigating the rigidly rotating disc of dust with constant specific charge, we find that it leads to an extreme Kerr-Newman black hole in the ultra-relativistic limit. A necessary and sufficient condition for a black hole limit is, that the electric potential in the co-rotating frame is constant on the disc. In that case certain other relations follow. These relations are reviewed with a highly accurate post-Newtonian expansion. Remarkably it is possible to survey the leading order behaviour close to the black hole limit with the post-Newtonian expansion. We find that the disc solution close to that limit can be approximated very well by a "hyper\-extreme" Kerr-Newman solution with the same gravitational mass, angular momentum and charge.

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Martin Breithaupt, Yu-Chun Liu, Reinhard Meinel, Stefan Palenta. 2015-02-10. On the black hole limit of rotating discs of charged dust. https://doi.org/10.1088/0264-9381%2F32%2F13%2F135022

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