Phases as Hidden Variables of Quantum Mechanics

Quantum mechanical wave functions have phases. These phases either initial or acquired during time evolution usually do not enter the final expressions for observable physical quantities. Nevertheless in many cases the observable physical quantities implicitly depend on the phases. Hence we may regard the phases as a sort of hidden variables of Quantum Mechanics. Neglecting the phase role makes inexplicable the peculiar quantum effects such as particle interference, Einstein-Podolsky-Rosen correlation and many others. To the contrary the adequate inclusion of phases into consideration reduces QM puzzles and mysteries to simple and obvious triviality.