Hilbert Space Representation of an Algebra of Observables for q-Deformed   Relativistic Quantum Mechanics
  Using a representation of the q-deformed Lorentz algebra as differential operators on quantum Minkowski space, we define an algebra of observables for a q-deformed relativistic quantum mechanics with spin zero. We construct a Hilbert space representation of this algebra in which the square of the mass $ p^2 $ is diagonal. 
W. Zippold