Domain Wall Spacetimes: Instability of Cosmological Event and Cauchy Horizons

TL;DR

This paper investigates the stability of cosmological event and Cauchy horizons in plane symmetric domain wall spacetimes, demonstrating that perturbations lead to curvature singularities, rendering the horizons unstable.

Contribution

It provides a detailed analysis showing that both horizons become unstable and turn into singularities under perturbations, highlighting their inherent instability.

Findings

Horizons become curvature singularities under perturbations

Singularities are light-like and strong, with unbounded tidal forces

Both horizons are unstable against null fluid and scalar field perturbations

Abstract

The stability of cosmological event and Cauchy horizons of spacetimes associated with plane symmetric domain walls are studied. It is found that both horizons are not stable against perturbations of null fluids and massless scalar fields; they are turned into curvature singularities. These singularities are light-like and strong in the sense that both the tidal forces and distortions acting on test particles become unbounded when theses singularities are approached.