Light interference and the absence of definite values of measured quantities a priori

The peculiarities of the behavior of photons in various experimental situations are considered. Variants of double-beam interference of a single photon and the possibility of forming a standing wave by this photon are analyzed; three-beam interference is also discussed. The effects observed in this case prove the absence of particular values of the measured quantities up to the moment of measurement; in the latter case, the number of photons in the field does not a priori have a certain value, in spite of the fact that the system is in the energy state. An experiment is also considered that proves the absence of a certain phase and the phase difference of photons in the Fock state, which makes it possible to treat different types of theories of hidden parameters, including nonlocal ones, more critically.