RESEARCH ON SUPERFLUIDITY AND SUPERCONDUCTIVITY ON THE BASIS OF THE FERMI-LIQUID CONCEPT

This review develops the Fermi liquid approach to the theory of superf luidity (superconductivity) based on the extension of combinatorial ex pression for the entropy for the case when the state of the Fermi liqu id is described not only by a normal distribution function but by an a bnormal distribution function and the state of the Bose liquid is desc ribed by these and by overcondensate amplitude as well. The energy of superfluid Fermi and Bose liquids is specified in the form of a functi onal of these functions. The Fermi liquid approach is equivalent to BC S theory in the weak interaction approximation. The interaction of Fer mi liquid with electromagnetic field is included in a gauge-invariant way. The theory of triplet pairing is developed as well as the theory of singlet pairing. On the base of unified variation principle leading to the theory of superfluidity (superconductivity) Londons' equations and Ginsburg-Landau's equation are obtained. Applications of the theo ry connected with construction of ideal two-component hydrodynamics eq uations are considered.