Does a domain wall emit gravitational waves? -- General-relativistic perturbative treatment

TL;DR

This paper investigates whether a planar domain wall in a general relativistic setting emits gravitational waves, concluding it does not spontaneously emit but can scatter incident waves, using a gauge-invariant perturbative approach.

Contribution

It provides a first-order gauge-invariant analysis showing domain walls do not spontaneously emit gravitational waves in a Minkowskian background.

Findings

Domain walls do not emit gravitational waves spontaneously.

They can scatter incident gravitational waves.

The analysis uses a gauge-invariant perturbative framework.

Abstract

The behavior of gravitational wave perturbations on a locally Minkowskian spacetime background containing a planar domain wall is investigated in the gauge-invariant general relativistic framework. It is shown that for this particular background the domain wall does not emit gravitational waves spontaneously by its free oscillation in the first order, although it scatters incidental gravitational waves.