GAUGE PROPERTIES OF CONSERVED-CURRENTS IN ABELIAN VERSUS NON-ABELIAN THEORIES

We clarify the physical origin of the difference between gauge propert ies of conserved currents in Abelian and non-Abelian theories. In the latter, but not in the former, such currents can always be written on- shell as gauge invariants module identically conserved, superpotential , terms. For the ''isotopic'' vector and the stress tenser currents of spins one and two respectively, we explain this difference by the fac t that the non-Abelian theories are just the self-coupled versions of the Abelian ones using these currents as sources. More precisely, we i ndicate how the self-coupling turns the noninvariantizable Abelian con served currents into (on-shell) superpotentials. The fate of other con served currents is also discussed.