Nambu-Jona-Lasinio-type effective Lagrangian: anomalies and nonlinear Lagrangian of low-energy, large-N QCD

We present a qualitative derivation of the chiral model from QCD. This is based on using a Nambu-Jona-Lasinio-type effective Lagrangian as an intermediate step. A detailed derivation of the anomalous low-energy Wess-Zumino term is presented. This includes vector, axial-vector, and pseudoscalar particles. The low-energy scale is set by H¯ ~ < Ψ¯Ψ >. We also present the low-energy nonlinear chiral model which generalizes the Skyrme model. The possibility of soliton solutions is indicated. There is a possible application of these ideas to electroweak theory