Positivity and the Axial-Vector Current in Quantum Electrodynamics

In finite theories of quantum electrodynamics, positivity implies d> 3 for the dimension d of an axial-vector current J/sub 5 mu / with nonzero anomaly. This result is not contradicted in the Johnson-Baker-Willey and Adler models: Arguments for the neglect of intenal fermion creation and annihilation fail for J/ sub 5 mu / amplitudes because illegal skelet on expansions are involved.