Dynamics of Domain Walls for Split and Runaway Potentials

TL;DR

This paper studies the evolution of domain walls in runaway potentials, showing they can persist long enough to impact cosmic structures without conflicting with CMB observations.

Contribution

It demonstrates that domain wall dynamics in runaway potentials are similar to those in double well potentials and identifies conditions that prolong their lifetime.

Findings

Domain walls can survive long enough to influence cosmic power spectra.

Compensation effects can stabilize domain walls against rapid decay.

Long-lived domain walls are compatible with CMB anisotropy constraints.

Abstract

We demonstrate that the evolution of wall-like inhomogeneities in run-away potentials, characteristic of dynamical supersymmetry breaking and moduli stabilisation, is very similar to the evolution of domain wall networks associated with double well potentials. Instabilities that would lead to a rapid decay of domain walls can be significantly ameliorated by compensation effects between a non-degeneracy of the vacua and a biased initial distribution, which can be naturally expected in a wide class or particle physics models that lead to out-of-equilibrium phase transitions. Within this framework, it is possible to obtain domain walls that live long enough to be relevant for the cosmic power spectrum and galaxy clustering, while being compatible with the observed cosmic microwave background anisotropies.