  Moduli, modulini and the gravitino have gravitational-strength interactions,
and thermal collisions after reheating create all of them with roughly the same
abundance. With their mass of order $100\GeV$, corresponding to
gravity-mediated supersymmetry breaking, this leads to the well-known bound
$\gamma T\sub R\lsim 10^9\GeV$ on the reheat temperature, where $\gamma\leq 1$
is the entropy dilution factor. The vacuum fluctuation also creates these
particles, with abundance determined by the solution of the equation for the
mode function. Taking the equation in each case to be the one corresponding to
a free field, we consider carefully the behaviour of the effective mass during
the crucial era after inflation. It may have a rapid oscillation, which does
not however affect the particle abundance. Existing estimates are confirmed;
the abundance of modulini and (probably) of moduli created from the vacuum is
less than from thermal collisions, but the abundance of gravitinos may be much
bigger, leading to a tighter bound on $T\sub R$ if supersymmetry breaking is
gravity-mediated. It is noted that in the case of gauge-mediated supersymmetry
breaking, the abundance of the gravitino may be sufficient to make it a dark
matter candidate.
