The High Temperature Phase of QCD and U(1)_A Symmetry

Inequalities for QCD functional integrals are used to establish that the high temperature chirally restored phase of QCD is effectively symmetric under $U(N_f) \times U(N_f)$ rather than $SU(N_f) \times SU(N_f)$. There are no effects due to anomalous breaking of $U(1)_A$ on correlation functions in this phase.