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arXiv · 1602.01833

Near-horizon Kerr Magnetosphere

Samuel E. Gralla·Alexandru Lupsasca·Andrew Strominger
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Abstract

We exploit the near-horizon conformal symmetry of rapidly spinning black holes to determine universal properties of their magnetospheres. Analytic expressions are derived for the limiting form of the magnetosphere in the near-horizon region. The symmetry is shown to imply that the black hole Meissner effect holds for free Maxwell fields but is generically violated for force-free fields. We further show that in the extremal limit, near-horizon plasma particles are infinitely boosted relative to accretion flow. Active galactic nuclei powered by rapidly spinning black holes are therefore natural sites for high-energy particle collisions.

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Samuel E. Gralla, Alexandru Lupsasca, Andrew Strominger. 2016-02-04. Near-horizon Kerr Magnetosphere. https://doi.org/10.1103/physrevd.93.104041

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