The Graviton Tail almost Completely Wags the Dog
  One graviton loop corrections to the vacuum polarization on de Sitter show
two interesting infrared effects: a secular enhancement of the photon electric
field strength and a long range running of the Coulomb potential. We show that
the first effect derives solely from the "tail" term of the graviton
propagator, but that the second effect does not. Our result agrees with the
earlier observation that the secular enhancement of massless fermion mode
functions derives from solely from the tail term. We discuss the implications
this has for the important project of generalizing to quantum gravity the
Starobinsky technique for summing the series of leading infrared effects from
inflationary quantum field theory.
