  New aspects of parametrically resonant heating of a relativistic scalar
O(2)-symmetric self-interacting field are presented. This process is a
candidate for reheating at the end of the early-universe epoch of inflation.
Although a model with a fully O(2)-symmetric ground state is used, transient,
metastable spontaneous symmetry breaking can be observed. This manifests itself
in the form of persistent regimes of opposite and, inside these, uniform charge
overdensities separated by thin lines and walls similar to topological defects,
in two and three spatial dimensions, respectively. The configuration is found
to correspond to an attractive non-equilibrium fixed point of the underlying
dynamic equations which prevents thermalisation over an extended period of
time.
