Black holes and magnetic fields
Abstract
Stationary axisymmetric magnetic fields are expelled from outer horizons of black holes as they become extremal. Extreme black holes exhibit Meissner effect also within exact Einstein--Maxwell theory and in string theories in higher dimensions. Since maximally rotating black holes are expected to be astrophysically most important, the expulsion of the magnetic flux from their horizons represents a potential threat to an electromagnetic mechanism launching the jets at the account of black-hole rotation.
Cite
@article{arxiv.astro-ph/0610841,
title = {Black holes and magnetic fields},
author = {J. Bicak and V. Karas and T. Ledvinka},
journal= {arXiv preprint arXiv:astro-ph/0610841},
year = {2007}
}
Comments
One figure and a reference added to match the final version after proof. To appear in Proceedings of "Black Holes: from Stars to Galaxies", IAU Symposium No. 238 (21-25 August 2006, Prague), eds. V. Karas & G. Matt, Cambridge University Press, p. 139