Andersson N, Glampedakis K
Department of Mathematics, University of Southampton, Southampton SO17 1BJ, United Kingdom.
Phys Rev Lett. 2000 May 15;84(20):4537-40. doi: 10.1103/PhysRevLett.84.4537.
We discuss the late-time behavior of a dynamically perturbed Kerr black hole. We present analytic results for near-extreme Kerr black holes that show that the large number of virtually undamped quasinormal modes that exist for nonzero values of the azimuthal eigenvalue m combine in such a way that the field oscillates with an amplitude that decays as 1/t at late times. This prediction is verified using numerical time evolutions of the Teukolsky equation. We argue that the observed behavior can be understood in terms of the presence of a "superradiance resonance cavity" immediately outside the black hole, and discuss whether it may be relevant for astrophysical black holes.
我们讨论了动态微扰克尔黑洞的晚期行为。我们给出了近极端克尔黑洞的解析结果，这些结果表明，对于方位角本征值(m)的非零值存在的大量几乎无阻尼的准正则模，它们以这样一种方式组合，使得场在晚期以(1/t)衰减的振幅振荡。利用特克尔方程的数值时间演化验证了这一预测。我们认为，观测到的行为可以通过黑洞外部紧邻的“超辐射共振腔”的存在来理解，并讨论了它是否可能与天体物理黑洞相关。
