  The axion particle may or may not exist, but the axion field can be used, as
shown here, in an explicitly local formulation of a chiral U(1) gauge theory
with both classical and quantum gauge invariance. Nonabelian analogues of axion
fields, which have recently been introduced, can be used, together with their
special symmetries, in a similar construction of nonabelian chiral gauge
theories. As in known cases, the gauge symmetry is broken and the gauge boson
acquires a mass by swallowing the axions which are therefore not physical in
this construction.
