Cosmic Censorship, Black Holes and Integer-spin Test Fields

Abstract

It has been argued that, starting with a slightly sub-extremal Kerr black hole instead of an extremal one, it is possible to overspin a black hole past the extremal limit and turn it into a naked singularity by sending test bodies, if one neglects radiative and self-force effects. In this work we show that (i) an extremal Kerr black hole can not be overspun as a result of the interaction with massless integer spin test fields (scalar, electromagnetic, or gravitational), (ii) overspinning can be achieved if we start with a nearly extremal black hole instead, and (iii) for the scalar field, the argument applies to more general black holes, and also allows use of a more general field configuration. Our analysis also neglects radiative and self-force effects.

4 pages, no figures. In this version, Sections II and III are rewritten for a better derivation of the conclusion, which remains unchanged. Now approximately matches published version [has more detail in references]