  Quantum operators of coordinates and momentum components of a particle in
Minkowski space-time belong to a noncommutative algebra and give rise to a
quantum phase space. Under some constraints, in particular, the Lorentz
invariance condition, the algebra of observables, including Lorentz group
generators, depends on additional fundamental physical constants with the
dimensions of mass, length and action. Generalized symmetries in a quantum
phase space and some consequences for fundamental interactions of particles are
considered.
