Sweeping Away the Monopole Problem

Abstract

We propose a new solution to the cosmological monopole problem in which domain walls sweep away the magnetic monopoles and subsequently decay. The solution does not require extensive fine-tuning or model building; it works for the prototype $\mathrm{SU}(5)$ grand unification model. More generally, it shows that defect interactions can lead to ``defect erasure'' in phase transitions and that this can be relevant to early universe physics.