  Single-slit and two-slit interferometer measurements of electrons are
analyzed within the realistic model of particle propagation. In a step by step
procedure we show that all current models of interference are essentially
non-local and demonstrate that the treatment of the quantum theory of motion is
the simplest model for the scalar problem. In particular we give a novel
interpretation of the quantum potential Q, which should be regarded as a
non-classical and essentially statistical term describing the changes of the
quantum ensemble due to a change of the physical environment.
