SYMMETRY AND CORRELATION-FUNCTIONS IN THE HIGH-TEMPERATURE PHASE OF QCD

Simple group-theoretical arguments are used to demonstrate that in the high temperature (chirally restored) phase of QCD with N-f massless f lavours, all n-point correlation functions of quark bilinears are inva riant under U(1)(A) transformations provided n < N-f. In particular th is implies that the two-point correlation function in the eta' channel is identical to that in the pion channel for N-f > 2. Unlike previous work, this result does not depend on the topological properties of QC D and can be formulated without explicit reference to functional integ rals.