On the phase transitions in a Fermi-liquid. I. The transition, connected with the rotary symmetry breaking in momentum space

The phase transition in a Fermi-liquid caused by the rotary symmetry violation of the momentum space is considered. It is shown, that this phase transition is associated with a failure of one of the Pomeranchuk condition (normal state stability conditions). A structure of the flow densities of the additive motion integrals id found out near them phase transition point and a physical interpretation of the phase under consideration is given