Photon propagation in slowly varying inhomogeneous electromagnetic fields

Starting from the Heisenberg-Euler effective Lagrangian, we determine the photon current and photon polarization tensor in inhomogeneous, slowly varying electromagnetic fields. To this end, we consider background field configurations varying in both space and time, paying special attention to the tensor structure. As a main result, we obtain compact analytical expressions for the photon polarization tensor in realistic Gaussian laser pulses, as generated in the focal spots of high-intensity lasers. These expressions are of utmost importance for the investigation of quantum vacuum nonlinearities in realistic high-intensity laser experiments.Comment: 15 pages, 1 figure; some clarifications added, matches journal versio

Neutrino interactions with a weak slowly varying electromagnetic field

We derive the effective action for processes involving two neutrinos and two photons at energies much below the electron mass. We discuss several applications in which one or both photons are replaced by external fields. In particular, Cherenkov radiation and neutrino pair production in weak external fields are investigated for massive Dirac neutrinos.Comment: 7 pages, no figure

Neutrino-photon Scattering in a Magnetic Field

Previous calculations of photon-neutrino scattering in a constant background magnetic field are extended and corrected.Comment: Corrections to the labeling of the entries in Table

Master formulas for photon amplitudes in a combined constant and plane-wave background field

The worldline formalism has previously been used for deriving compact master formulas for the QED $N$ - photon amplitudes in vacuum, in a constant field and in a plane-wave field. Here we carry this program one step further by deriving master formulas for the scalar and spinor QED $N$-photon amplitudes in the background of the "parallel" special case of a combined constant and plane-wave field.Comment: 20 pages, no figures, typo in eq. (58) correcte