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arXiv · 1602.02385

How close can we approach the event horizon of the Kerr black hole from the detection of the gravitational quasinormal modes?

Takashi Nakamura·Hiroyuki Nakano
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Abstract

Using the WKB method, we show that the peak location ($r_{\rm peak}$) of the potential, which determines the quasinormal mode frequency of the Kerr black hole, obeys an accurate empirical relation as a function of the specific angular momentum $a$ and the gravitational mass $M$. If the quasinormal mode with $a/M \sim 1$ is observed by gravitational wave detectors, we can confirm the black-hole space-time around the event horizon, $r_{\rm peak}=r_+ +O(\sqrt{1-q})$ where $r_+$ is the event horizon radius. While if the quasinormal mode is different from that of general relativity, we are forced to seek the true theory of gravity and/or face to the existence of the naked singularity.

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Takashi Nakamura, Hiroyuki Nakano. 2016-02-07. How close can we approach the event horizon of the Kerr black hole from the detection of the gravitational quasinormal modes?. https://doi.org/10.1093/ptep/ptw026

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