Two-point function for the Maxwell field in flat Robertson-Walker spacetimes
arXiv:1310.7333 · doi:10.1103/PhysRevD.88.124018
Abstract
We obtain an explicit two-point function for the Maxwell field in flat Roberson-Walker spaces, thanks to a new gauge condition which takes the scale factor into account and assume a simple form. The two-point function is found to have the short distance Hadamard behavior.
4 pages, Revtex