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Floating Orbits, Superradiant Scattering and the Black-hole Bomb


Penrose1 and Christodoulou2 have shown how, in principle, rotational energy can be extracted from a black hole by orbiting and fissioning particles. Recently, Misner3 has pointed out that waves can also extract rotational energy (“superradiant scattering” in which an impinging wave is amplified as it scatters off a rotating hole). As one application of super-radiant scattering, Misner has suggested the possible existence of “floating orbits”, that is, orbits in which a particle radiatively extracts energy from the hole at the same rate as it radiates energy to infinity; thereby it experiences zero net radiation reaction.

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    Penrose, R., Revista Del Nuovo Cimento, 1, 252 (1969).

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    Christodoulou, D., Phys. Rev. Lett., 25, 1596 (1970).

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    Misner, C. W., Phys. Rev. Lett., 28, 994 (1972).

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    Carter, B., Phys. Rev., 174, 1559 (1968).

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    Boyer, R. H., and Lindquist, R. W., J. Math. Phys., 8, 265 (1967).

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    Zel'dovich, Ya. B., JETP Lett., 14, 270 (1971).

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