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Dynamics of scalar fields in the background of rotating black holes II: A note on superradiance

Nils Andersson·Pablo Laguna·Philippos Papadopoulos
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Abstract

We analyze the amplification due to so-called superradiance from the scattering of pulses off rotating black holes as a numerical time evolution problem. We consider the "worst possible case" of scalar field pulses for which superradiance effects yield amplifications $< 1%$. We show that this small effect can be isolated by numerically evolving quasi-monochromatic, modulated pulses with a recently developed Teukolsky code. The results show that it is possible to study superradiance in the time domain, but only if the initial data is carefully tuned. This illustrates the intrinsic difficulties of detecting superradiance in more general evolution scenarios.

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Nils Andersson, Pablo Laguna, Philippos Papadopoulos. 1998-02-23. Dynamics of scalar fields in the background of rotating black holes II: A note on superradiance. https://doi.org/10.1103/physrevd.58.087503

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