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On classical super-radiance in Kerr-Newman-anti-de Sitter black holes

Elizabeth Winstanley
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Abstract

We study in detail the modes of a classical scalar field on a Kerr-Newman-anti-de Sitter (KN-AdS) black hole. We construct sets of basis modes appropriate to the two possible boundary conditions (``reflective'' and ``transparent'') at time-like infinity, and consider whether super-radiance is possible. If we employ ``reflective'' boundary conditions, all modes are non-super-radiant. On the other hand, for ``transparent'' boundary conditions, the presence of super-radiance depends on our definition of positive frequency. For those KN-AdS black holes having a globally time-like Killing vector, the natural choice of positive frequency leads to no super-radiance. For other KN-AdS black holes, there is a choice of positive frequency which gives no super-radiance, but for other choices there will, in general, be super-radiance.

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Elizabeth Winstanley. 2001-06-20. On classical super-radiance in Kerr-Newman-anti-de Sitter black holes. https://doi.org/10.1103/physrevd.64.104010

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