Can Kerr Black Holes be Detected Through Gravitational Lensing Experiments?

chronnox
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Hello, i was studying kerr black holes and i think i can understand most of the theory behind it but i was wondering how can you detect black holes that are actually rotating?. I thought like sending two light rays from the same point (like gravitational lensing) but since the black hole is rotating there has to be something different than gravitational lensing. Do you guys know some experiments to detect kerr black holes?
 
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chronnox said:
Hello, i was studying kerr black holes and i think i can understand most of the theory behind it but i was wondering how can you detect black holes that are actually rotating?. I thought like sending two light rays from the same point (like gravitational lensing) but since the black hole is rotating there has to be something different than gravitational lensing. Do you guys know some experiments to detect kerr black holes?
Lense-Thirring effect, for example.
http://scienceworld.wolfram.com/physics/Lense-ThirringEffect.html
 
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You can also get some idea of spin by looking at the inner edge of the accretion disk (or the marginally stable orbit) which ranges from 6M for static black holes (a/M=0) up to M for maximal Kerr black holes (a/M=1).
 
thanks for the examples.
 
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