Tests of Large Nc QCD from Hadronic τ Decay

We use the ALEPH Collaboration data on vector and axial-vector spectral functions to test simple duality properties of QCD in the large N_c limit, which emerge in the approximation of a minimal hadronic ansatz of a spectrum of narrow states. These duality properties relate the short- and long-distance behaviors of specific correlation functions, which are order parameters of spontaneous chiral symmetry breaking, in a way that we find well supported by the data.