Defect-antidefect pair production via field oscillations

We show that the mechanism of vortex-antivortex pair production via field oscillations, earlier proposed by two of us for systems with first order transitions in the presence of explicit symmetry breaking, is in fact generally applicable. We further argue that this mechanism applies to all sorts of topological defects (e.g., strings, monopoles, textures) and for second order transitions as well (involving quench from high temperature). We also show this explicitly by numerically simulating the production of vortex-antivortex pairs by the decay of bubble walls for a U(1) global theory in the absence of any explicit symmetry breaking.