Excitation of Photons by Inflationary Gravitons
  We use a recent result for the graviton contribution to the one loop vacuum
polarization to solve the effective field equations for dynamical photons on de
Sitter background. Our results show that the electric field experiences a
secular enhancement proportional to the number of inflationary e-foldings. We
discuss the minimum this establishes for primordial inflation to seed cosmic
magnetic fields.
