  The claim some years ago, contrary to all textbooks, that the angular
momentum of a photon (and gluon) can be split in a gauge-invariant way into an
orbital and spin term, sparked a major controversy in the Particle Physics
community. A further cause of upset was the realization that the gluon
polarization in a nucleon, a supposedly physically meaningful quantity,
corresponds only to the gauge-variant gluon spin derived from Noether's
theorem, evaluated in a particular gauge. On the contrary, Laser Physicists
have, for decades, been happily measuring physical quantities which correspond
to orbital and spin angular momentum evaluated in a particular gauge. This
paper reconciles the two points of view.
