Exact Sum Rules at Finite Temperature and Chemical Potential and their Application to QCD

Abstract

Within the framework of the operator product expansion (OPE) and the renormalization group equation (RGE), we show that the temperature and chemical potential dependence of the zeroth moment of a spectral function (SF) in an asymptotically free theory is completely determined by the one-loop structure of the theory. This exact result constrains the qualitative shape of SF's, and implies striking phenomenological effects near phase transitions.

Comments: 5 pages using world_sci.sty, which is appended to the file. Full postscript version available via anonymous ftp from risc0.ca.infn.it:/pub/private/lissia/infnca-th-94-18.ps (192.84.132.4) To appear in the Proceedings of the ``Workshop on Quantum Infrared Physics'', Paris, France, 6-10 June 1994