CHIRAL PHASE-TRANSITION IN QCD FOR FINITE TEMPERATURE AND DENSITY

The chiral phase diagram in the plane of chemical potential and temperature, as derived by studying the effective potential for the fermion sector of QCD with three flavours (in the chiral limit), shows the existence of a tricritical point. In the case of continuous transitions, the critical exponents both for the fermion condensate and for the pion decay constant are the classical ones.