Relativity Seminar

High energy particle collisions near black holes and naked singularities: general explanation and classification of scenarios

If two particles collide near a rotating black hole, their energy in the center of mass frame E_c.m. can become unbounded under certain conditions. This is the Banados-Silk-West (BSW) effect. We give a brief review and general physical explanation from the geometric and kinematic viewpoints. In doing so, the Killing energy E of debris at infinity remains, in general, restricted. If E is also unbounded, this is called the super-Penrose process. We elucidate when such a process is possible and give full classification of corresponding relativistic objects for rotating space-times. In particular, we show that it is possible for rotating wormholes. The key role in consideration is played by the Wald inequalities. We also discuss briefly the case of a pure electric super-Penrose process near black holes and singularities. It is valid even in the flat space-time.