  In this paper, we propose to draw attention to the stability criterion of the
superconductor current state. We use for this purpose the rough systems
mathematical apparatus allowing us to relate the desired criterion with the
dielectric permittivity of the matter and to identify the type of all possible
phonons trajectories in its superconducting state. The state of
superconductivity in the matter can be explained only by the phonons behavior
peculiarity. And on the basis of the above-mentioned assumption, the
corresponding mathematical model is constructed.
