On the Feynman Rules of Massive Gauge Theory in Physical Gauges
by Dr. Junmou Chen (KIAS)
at CTPU Seminar Room
For massive gauge theory in physical gauges, both gauge fields and goldstone fields posses the same pole masses. Different from R_\xi gauge, this allows the interpretation of longitudinal polarization vectors as interpolated by both gauge fields and goldstone fields. I treat gauge fields and goldstone fields uniformly as 5-component fields and rederive the Feynman rules -- including both propagators and vertices, which prove to be largely simplified and share similarities to massless gauge theory. We illustrate the results in the Higgs-Kibble model, with SU(2) gauge group and unbroken custodial symmetry between the goldstone modes. This treatment can bring simplifications to the calculations of the Standard Model.