Date:
26. April 2024 - 11:45 to 13:00
Speaker:
Øyvind Christiansen (University of Oslo)
The study of domain walls and topological defects has a rich history in cosmology and they provide a wide range of novel phenomenology to experimentally test them. The motivations that they have been studied under include seeding the initial overdensities for structure formation, driving inflation, seeding a stochastic gravitational wave background like the one in NANOGrav, and providing the skeleton for the formation of larger structures than you would expect in LCDM. They have furthermore been linked to resolutions of some of the late-time cosmological tensions. I will in this talk present the (a)symmetron dark energy model, that exhibits late-time cosmological domain walls, and our implementation of it in the cosmological N-body code gevolution. I present some details on the domain walls' dynamics, their GW emission, their effect on clustering, and some observational signatures.