Pion transitions and models of chiral symmetry

We describe a set of pion-decay and scattering amplitudes which are described by only two low-energy parameters in the effective chiral Lagrangian of QCD. After a phenomenological analysis of the data, we demonstrate how the effective-Lagrangian framework correlates the many predictions of these reactions which have been made in the literature using a variety of models with chiral symmetry. A comparison with the data then also determines which model best represents QCD. Not surprisingly, the winner is a form of vector dominance