Collapsing domain walls beyond Z2

Discrete symmetries are widely imposed in particle theories. It is well known that the spontaneous breaking of discrete symmetries leads to domain walls. Current studies of domain walls have focused on those from the spontaneous breaking of a Z2 symmetry. Larger discrete symmetries have multiple degenerate vacua, leading to domain walls which are in principle different from the simplest Z2 domain wall. We take domain walls from ZN symmetry breaking as an illustrative study, and study in detail the Z3 case, in which semianalytical results for the tension and thickness of domain walls are derived. Explicit symmetry-breaking terms lead to the dynamics of domain walls collapsing in a more more complicated way than the Z2 case. Gravitational wave signals deviate from those from Z2 domain walls.