Instabilities of massive scalar perturbations of a rotating black hole

✍ Scribed by Theodoros J.M Zouros; Douglas M Eardley

• Publisher: Elsevier Science
• Year: 1979
• Tongue: English
• Weight: 876 KB
• Volume: 118
• Category: Article
• ISSN: 0003-4916
• DOI: 10.1016/0003-4916(79)90237-9

✦ Synopsis

We study the stability of a massive scalar field in the exterior metric of a rotating Kerr black hole. An argument based on energy conservation shows, under some strong technical assumptions, that unstable normal modes exist. These unstable modes can be interpreted as wave packets in bound, superradiant orbits. A JWKB estimate of the fastest growth rate gives lO-'M-l exp(--1.84Mp) in the case Mp 3 1, where M is the mass of the hole and ~1 is the mass of the field. The existence of unstable normal modes has significant implications for quantum particle creation by rotating black holes, which we attempt to assess.