  While inflaton loops in the Euclidean vacuum generally have a negligible
contribution to the power spectrum, loop effects can be substantially larger
when the inflaton is in a non-thermal vacuum state. As an example, we show that
in a truncated alpha-vacuum these loop effects are enhanced by the ratio of the
Planck scale to the Hubble scale during inflation. The details of the
inflationary models determine whether the coupling constants suppress the loop
corrections relative to the tree level result.
