Photon-photon interaction in a photon gas
Theory Division, CERN - CH-1211 Geneva, Switzerland
and Institut für Theoretische Physik, Universität Giessen - 35392
Accepted: 4 October 2000
Using the effective Lagrangian for the low-energy photon-photon interaction, the lowest-order photon self-energy at finite temperature and in non-equilibrium is calculated within the real-time formalism. The Debye mass, the dispersion relation, the dielectric tensor, and the velocity of light following from the photon self-energy are discussed. As an application, we consider the interaction of photons with the cosmic microwave background radiation.
PACS: 11.10.Wx – Finite-temperature field theory / 14.70.Bh – Photons / 98.70.Vc – Background radiations
© EDP Sciences, 2000