  The meaning of local observables is poorly understood in gauge theories, not
to speak of quantum gravity. As a step towards a better understanding we study
asymptotic (infrared) transformation in local quantum physics. Our observables
are smeared by test functions, at first vanishing at infinity. In this context
we show that the equations of motion can be seen as constraints, which generate
a group, the group of space and time dependent gauge transformations.This is
one of the main points of the paper. Infrared nontrivial effects are captured
allowing test functions which do not vanish at infinity. These extended
operators generate a larger group. The quotient of the two groups generate
superselection sectors, which differentiate different infrared sectors. The BMS
group changes the superselection sector, a result long known for its Lorentz
subgroup. It is hence spontaneously broken. Ward identities implied by the
gauge invariance of the S-matrix generalize the standard results and lead to
charge conservation and low energy theorems. Their validity does not require
Lorentz invariance.
