Magnetic monopole - domain wall collisions

TL;DR

This paper investigates the interactions between magnetic monopoles and domain walls in a Grand Unified theory, revealing two distinct outcomes based on their internal orientation, which influence the evolution of topological defects after phase transitions.

Contribution

It provides a detailed analysis of monopole-wall interactions in a specific GUT model, identifying the conditions leading to either monopole passage or unwinding upon collision.

Findings

Monopoles can pass through domain walls without destruction.

Monopoles can unwind when hitting the wall, depending on orientation.

Only two interaction outcomes are possible in the studied model.

Abstract

Interactions of different types of topological defects can play an important role in the aftermath of a phase transition. We study interactions of fundamental magnetic monopoles and stable domain walls in a Grand Unified theory in which $SU(5) \times Z_2$ symmetry is spontaneously broken to $SU(3)\times SU(2)\times U(1)/Z_6$. We find that there are only two distinct outcomes depending on the relative orientation of the monopole and the wall in internal space. In one case, the monopole passes through the wall, while in the other it unwinds on hitting the wall.