Application of the 5-Dimensional Spin to the Theory of Superfluid 3He

Abstract

By noting that the pair operators characterizing the Bose condensed state of spin-triplet pairs are the generators of the 5-dimensional rotation group, a systematic theory of superfluid 'He is developed. It is applied to the calculation of the spin susceptibility with higher order Fermi liquid corrections, and also to the derivation of the Leggett equation from the pairing hamiltonian. It is remarked that the order parameter undergoes a change in the first order of the applied magnetic field.