Classical transitions with the topological number changing in the early Universe

Understand

We consider classical dynamics of two real scalar fields within a model with the potential having a saddle point.

• The solitons of such model are field configurations that have the form of closed loops in the field space.
• We study the formation and evolution of these solitons, in particular, the conditions at which they could be formed even when the model potential has only one minimum.
• These non-trivial field configurations represent domain walls in the three-dimensional physical space.