Black hole bomb

A black hole bomb is the name given to a physical effect utilizing how a bosonic field impinging on a rotating black hole can be amplified through superradiant scattering. An additional condition which must be met is that the field must have a rest mass different from zero. The scattered wave will then be reflected back and forth between the mass term and the black hole becoming amplified on each reflection. The growth of the field is asserted to be exponential and unstable. The mechanism by which the black hole bomb functions is called superradiant instability.

The first discussion of this effect was by Press and Teukolsky in 1972.