Domain walls are defects that form during certain phase transitions, and can, for example, be viewed in the ice sheet of a frozen lake. The study of domain walls and topological defects has a rich history in cosmology, and they provide a wide range of novel phenomenology to test experimentally. The motivations under which they have been studied include seeding the initial overdensities for structure formation, driving inflation, sourcing a stochastic gravitational wave background, and providing the skeleton for the formation of larger structures than expected in the standard model of cosmology. They may also be linked to resolving some of the late-time cosmological tensions. Their non-linear and dynamic nature motivates numerical studies that remain challenged by the need to resolve a wide range of scales. In this talk, I will present results from our implementation of domain walls in the massively parallelised N-body and lattice field code AsGRD, focusing on their dynamics and the generation of gravitational waves in the late and non-linear Universe.
