  The viability of a given model for inflation is determined not only by the
form of the inflaton potential, but also by the initial inflaton field
configuration. In many models, field configurations which are otherwise
well-motivated nevertheless fail to induce inflation, or fail to produce an
inflationary epoch of duration sufficient to solve the horizon and flatness
problems. In this paper, we propose a mechanism which enables inflation to
occur even with such initial conditions. Our mechanism involves multiple scalar
fields which experience a time-dependent mixing. This in turn leads to a
"re-overdamping" phase as well as a parametric resonance which together
"slingshot" the inflaton field from regions of parameter space that do not
induce inflation to regions that do. Our mechanism is flexible, dynamical, and
capable of yielding an inflationary epoch of sufficiently long duration. This
slingshot mechanism can therefore be utilized in a variety of settings and
thereby enlarge the space of potentially viable inflation models.
