Electrodynamic Effects of Inflationary Gravitons
  We calculate the one-loop corrections from inflationary gravitons to the
electromagnetic fields of a point charge and a point magnetic dipole on a
locally de Sitter space background. Results are obtained both for an observer
at rest in co-moving coordinates, whose physical distance from the sources
increases with the expanding universe, and for an observer at rest in static
coordinates, whose physical distance from the sources is constant. The fields
of both sources show the de Sitter analogs of the fractional $G/r^2$
corrections which occur in flat space, but there are also some fractional $G
H^2$ corrections due to the scattering of virtual photons from the vast
ensemble of infrared gravitons produced by inflation. The co-moving observer
perceives the magnitude of the point charge to increase linearly with co-moving
time and logarithmically with the co-moving position, however, the magnetic
dipole shows only a negative logarithmic spatial variation. The static observer
perceives no secular change of the point charge but he does report a secular
enhancement of the magnetic dipole moment.
