On white holes as particle accelerators

TL;DR

This paper explores how white holes could theoretically serve as particle accelerators, enabling ultrahigh energy collisions near black hole horizons, with implications for understanding extreme astrophysical phenomena.

Contribution

It introduces a novel scenario involving white holes in black hole metrics to achieve unbounded collision energies, expanding the theoretical framework of high-energy astrophysical processes.

Findings

Unbounded collision energy requires particle 2 to pass near the bifurcation point.

White holes can potentially act as natural particle accelerators.

Analogy with horizon collisions provides new insights into extreme energy events.

Abstract

We analyze scenarios of particle collisions in the metric of a nonextremal black hole that can potentially lead to ultrahigh energy $E_{c.m.}$ in their centre of mass frame. Particle 1 comes from infinity to the black hole horizon while particle 2 emerges from a white hole region. It is shown that unbounded $E_{c.m.}$ $\ $require that particle 2 pass close to the bifurcation point. The analogy with collisions inside the horizon is discussed.