  The infrared behaviour of the gauge-invariant dressed fermion propagator in
massless QED_3 is discussed for three choices of dressing. It is found that
only the propagator with the isotropic (in three Euclidean dimensions) choice
of dressing is acceptable as the physical fermion propagator. It is explained
that the negative anomalous dimension of this physical fermion does not
contradict any field-theoretical requirement.

High Energy Physics - Theory;Superconductivity;High Energy Physics - Phenomenology