Explicit construction of anomalies

Abstract

We demonstrate explicitly the dimensional ladder which links the d + 2 dimensional chiral anomaly, the d + 1 dimensional parity anomaly and the d-dimensional gauge anomaly. We solve the two- and three-dimensional problems of massless fermions in a background instanton gauge potential, discuss the structure of the anomalous effective actions and show the equality of the topological invariants relevant to the different anomalies. © 1987.