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arXiv · 1411.2609

Rotating black holes can have short bristles

Shahar Hod
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Abstract

The elegant `no short hair' theorem states that, if a spherically-symmetric static black hole has hair, then this hair must extend beyond 3/2 the horizon radius. In the present paper we provide evidence for the failure of this theorem beyond the regime of spherically-symmetric static black holes. In particular, we show that rotating black holes can support extremely short-range stationary scalar configurations (linearized scalar `clouds') in their exterior regions. To that end, we solve analytically the Klein-Gordon-Kerr-Newman wave equation for a linearized massive scalar field in the regime of large scalar masses.

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Shahar Hod. 2014-11-10. Rotating black holes can have short bristles. https://doi.org/10.1016/j.physletb.2014.10.062

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