摘要
The pressure of a fermion system is expressed as a mass integral over the full two-point spectral densities within the real time formalism by use of the Keldysh representation for the propagators.This simpliSes the calculation significantly and allows a Dyson resummation.The expression is used to demonstrate that potential infrared divergences are rendered harmless.We apply it to check the pressures of an ideal fermion gas and of a chemically non-equilibrated quantum chromodynamics plasma.
作者
侯德富
U.Heinz
李家荣
HOU De-fu;U.Heinz;LI Jia-rong(Institute of Particle Physics,Huazhong Normal University,Wuhan 430079;Institut fur Theoretische Physik,Universitat Regensburg,D-93040 Regensburg,Germany)
基金
Supported by the Deutsche Forschungsgemeinschaft(DFG)
the Bundesministerium fur Bildung und Forschung(BMBF)
the National Natural Science Foundation of China under Grant No.19775017
the Gesellschaft fur Schwerionenforschung(GSI).
