Super-Penrose Process for Nonextremal Black Holes

Abstract

We consider particle collisions in the background of nonextremal spherically symmetric static black holes. It is shown that debris of collision can have indefinitely large energy at infinity; i.e., the super-Penrose process can occur. This property is sharply contrasted with that of rotating black holes for which it is already established that the super-Penrose process is forbidden. The Reissner–Nordström black hole serves as an example. If an external central force exerts on particles, even the Schwarzschild background is suitable for the super-Penrose process.