  A number of scalar field models proposed as alternatives to the standard
inflationary scenario involve contracting phases which precede the universe's
present phase of expansion. An important question concerning such models is
whether there are effects which could potentially distinguish them from purely
expanding cosmologies. Vector perturbations have recently been considered in
this context. At first order such perturbations are not supported by a scalar
field. In this paper, therefore, we consider second order vector perturbations.
We show that such perturbations are generated by first order scalar mode-mode
couplings, and give an explicit expression for them. We compare the magnitude
of vector perturbations produced in collapsing models with the corresponding
amplitudes produced during inflation, using a number of suitable power-law
solutions to model the inflationary and collapsing scenarios. We conclude that
the ratios of the magnitudes of these perturbations depend on the details of
the collapsing scenario as well as on how the hot big bang is recovered, but
for certain cases could be large, growing with the duration of the collapse.
