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arXiv · 1409.1593

Kerr-Newman scalar clouds

Carolina L. Benone·Luis C. B. Crispino·Carlos Herdeiro·Eugen Radu
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Abstract

Massive complex scalar fields can form bound states around Kerr black holes. These bound states -- dubbed scalar clouds -- are generically non-zero and finite on and outside the horizon; they decay exponentially at spatial infinity, have a real frequency and are specified by a set of integer "quantum" numbers (n,l,m). For a specific set of these numbers, the clouds are only possible along a 1-dimensional subset of the 2-dimensional parameter space of Kerr black holes, called an existence line. In this paper we make a thorough investigation of the scalar clouds due to neutral (charged) scalar fields around Kerr(-Newman) black holes. We present the location of the existence lines for a variety of quantum numbers, their spatial representation and compare analytic approximation formulas in the literature with our exact numerical results, exhibiting a sometimes remarkable agreement.

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Carolina L. Benone, Luis C. B. Crispino, Carlos Herdeiro, Eugen Radu. 2014-09-12. Kerr-Newman scalar clouds. https://doi.org/10.1103/physrevd.90.104024

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