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arXiv · 1306.3137

Superradiance without event horizons in General Relativity

Maurício Richartz·Alberto Saa
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Abstract

Superradiant scattering processes are studied in general relativistic systems which, unlike rotating and/or charged black holes, do not exhibit an event horizon. Inspired by Zel'dovich's seminal works on the amplification of waves by a rotating cylinder, we analyse, in the context of General Relativity, the possibility of superradiance for electromagnetic waves reflecting off a rotating star and for charged scalar perturbations impinging on a charged sphere. The role of energy dissipation in these systems is analysed and compared with the role of the event horizon in black hole superradiance.

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Maurício Richartz, Alberto Saa. 2013-06-13. Superradiance without event horizons in General Relativity. https://doi.org/10.1103/physrevd.88.044008

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