  The structure of transition amplitudes in field theory in a three-dimensional
space whose spatial coordinates are noncommutative and satisfy the SU(2) Lie
algebra commutation relations is examined. In particular, the basic notions for
constructing the observables of the theory as well as subtleties related to the
proper treatment of $\delta$ distributions (corresponding to conservation laws)
are introduced. Explicit examples are given for scalar field theory amplitudes
in the lowest order of perturbation.
