Is is necessary to abandon the ψ function in quantum gravitation?

Hawking's conclusion that a pure state of an elementary particle converts into a mixed state as a result of a coupling with real and virtual black holes and that it is necessary to abandon the description of elementary particles by means of a ψ function in quantum gravitation is subjected to a critical analysis. An examination of a specific example - the motion of particles of nonzero mass and of photons in the field of a charged black hole - does not support Hawking's conclusion. Ellis's estimates of a lower (energy) limit on the applicability of quantum mechanics has been improved by 40 orders of magnitude