Energy extraction from extremal charged black holes due to the BSW effect

TL;DR

This paper investigates the BSW effect near extremal charged black holes, demonstrating scenarios where particles can gain unbounded energy and mass, making high-energy products potentially observable at infinity.

Contribution

It extends the BSW effect analysis to charged static black holes, showing that unlike the rotating case, there are scenarios with no upper bounds on energy and mass.

Findings

Unbounded energy and mass can be achieved near charged black holes.

High-energy products of collisions can be detected at infinity.

No upper bounds on E and m in certain scenarios.

Abstract

Two particles can collide in the vicinity of a rotating black hole producing the divergent energy in the centre of mass frame (the BSW effect). However, it was shown recently that an observer at infinity can register quite modest energies E and masses m which obey some upper bounds. In the present work the counterpart of the original BSW effect is considered that may occur even for radial motion of colliding particles near charged static black holes. It is shown that in some scenarios there are no upper bound on E and m . Thus the high-energetic and superheavy products of the BSW effect in this situation are, in principle, detectable at infinity.