The problem of phase transitions in superfluid and normal liquids

A new interpretation of the well-known spectrum obtained by Bogoliubov for boson gas and of the role of the angular velocity as a thermodynamic variable determining a phase transition of the second kind is presented. A new averaging method over clusters that results in a new spectral series and a different phase transition is suggested. This method is generalized to the classical equations, which permits conjecturing a phase transition with respect to velocity from a laminar flow to a turbulent one.