Post-Inflationary Evolution via Gravitation
  We study a class of non-local, purely gravitational models which have the
correct structure to reproduce the leading infrared logarithms of quantum
gravitational back-reaction during the inflationary regime. These models end
inflation in a distinctive phase of oscillations with slight and short
violations of the weak energy condition and should, when coupled to matter,
lead to rapid reheating. By elaborating this class of models we exhibit one
that has the same behaviour during inflation, goes quiescent until the onset of
matter domination, and induces a small, positive cosmological constant of about
the right size thereafter.
