QED Second Order Corrections on the Speed of Light at Low Temperature
arXiv:1308.4124
Abstract
We want to study thermal corrections on the speed of light at low temperature considering temperature dependence of photon vacuum polarization tensor at two-loop level in the standard QED. It is found that the heat bath behaves as a dispersive medium to the propagation of light and reduces its speed proprtional to the second order of temperature. Similiraties and differences with already known calculations which are based on Euler-Heisenberg Lagrangian and/or those using temperature dependent electromagnetic properties of the medium are discussed.
12 pages including an Appendix