High energy particle collisions near the bifurcation surface

TL;DR

This paper demonstrates that in generic nonextremal stationary black holes, particle collision energy can become unbounded near bifurcation surfaces and horizons, including cosmological horizons, revealing a universal property of such spacetime regions.

Contribution

It establishes the generic nature of unbounded collision energies near bifurcation surfaces in nonextremal stationary black holes, extending previous specific analyses.

Findings

Unbounded collision energy near bifurcation surfaces.

Applicability to cosmological horizons.

Includes analysis of de Sitter spacetime.

Abstract

We consider generic nonextremal stationary dirty black holes. It is shown that in the vicinity of any bifurcation surface the energy of collision of two particles in the centre of mass frame can grow unbound. This is a generic property that, in particular, includes collisions near the inner black hole horizon analyzed earlier by different methods. The similar results are also valid for cosmological horizons. The case of the de Sitter metric is discussed.