RealTime Thermal Green's Functions
Abstract
We study perturbative techniques for evaluating realtime Green's functions of relativistic fields in thermal equilibrium. Our primary conclusion is that a consistent perturbation theory for realtime thermal Green's functions must include contributions from all segments of the time integration contour C and three commonly used procedures for calculating realtime thermal Green's functions, which derive the same twocomponent finitetemperature Feynman rules, are incorrect. These three procedures are: the factorization prescription of Niemi and Semenoff; finite temperature canonical quantization combined with a limiting procedure; and thermo field dynamics. We examine each of the three procedures and exhibit its flaw and we show why the twocomponent finitetemperature formalism these procedures yield is incorrect. After presenting the correct realtime thermal Feynman rules, we calculate the finitetemperature effective potential and the finite temperature effective mass, both to oneloop order.
 Publication:

Ph.D. Thesis
 Pub Date:
 May 1987
 Bibcode:
 1987PhDT.........6I
 Keywords:

 FINITETEMPERATURE;
 Physics: Elementary Particles and High Energy