  The prospect of a time-dependent Higgs vacuum expectation value is examined
within the standard model of electroweak interactions. It is shown that the
classical equation of motion for the Higgs field admits a solution that is a
doubly-periodic function of time. The corresponding Dirac equation for the
electron field is equivalent to a second order differential equation with
doubly-periodic coefficients. In the limit of very large primitive period of
the Higgs background this equation can be solved in WKBJ approximation, showing
plane-wave solutions with a time-dependent distortion factor which can be made
arbitrarily small.
