Finite temperature field theory - hard thermal loops and the quark-gluon plasma

This dissertation is concerned with the study of finite temperature field theory in particular its application to a quark-gluon plasma, a heat bath consists entirely of quarks and gluons. Due to the problem of gauge dependence of the gluon damping rate in such a plasma, Braaten and Pisarski were led to the conclusion that this was due to the break down of perturbation theory. In order to restore the validity of perturbation calculation, resummation must be done. Central to their resummation programme are the quantities called hard thermal loops. These are part of the one loop Feynman diagrams and have various properties including gauge independence. We study these hard thermal loops. In particular, methods for extracting them are presented and their properties are shown and discussed. (Author)