Effects of Biases in Domain Wall Network Evolution

TL;DR

This paper investigates how biases affect the evolution and decay of domain wall networks in the early universe through extensive simulations, testing existing decay laws and providing new insights.

Contribution

It offers the first large-scale numerical simulations explicitly measuring velocities and tests decay laws for biased networks, clarifying their applicability.

Findings

Decay law matches simulations with biased potentials.

Decay law does not fit biased initial condition networks.

Larger simulations improve understanding of domain wall dynamics.

Abstract

We study the evolution of various types of biased domain wall networks in the early universe. We carry out larger numerical simulations than currently available in the literature and provide a more detailed study of the decay of these networks, in particular by explicitly measuring velocities in the simulations. We also use the larger dynamic range of our simulations to test previously suggested decay laws for these networks, including an ad-hoc phenomenological fit to earlier simulations and a decay law obtained by Hindmarsh through analytic arguments. We find the latter to be in good agreement with simulations in the case of a biased potential, but not in the case of biased initial conditions.