No horizons in pp-waves

TL;DR

This paper demonstrates that pp-wave backgrounds cannot have event horizons, discusses potential generalizations that could admit horizons, and presents a black string solution asymptotic to a five-dimensional plane wave background.

Contribution

It establishes the non-existence of horizons in pp-wave backgrounds and introduces a black string solution in a related setting.

Findings

pp-wave backgrounds cannot admit event horizons

a black string solution asymptotes to a five-dimensional plane wave

possible generalizations of pp-waves with horizons

Abstract

We argue that pp-wave backgrounds can not admit event horizons. We also comment on pp-wave generalizations which would admit horizons and show that there exists a black string solution which asymptotes to a five dimensional plane wave background.