Effects of Particle-Particle Interaction on the Moment of Inertia of Many-Fermion Systems

Abstract

It is shown that in the random-phase approximation the effect of particle-particle interaction on the moment of inertia of a many-fermion system moving under periodic boundary conditions vanishes when calculated on the "cranking" model of Inglis. This result is obtained by performing a unitary transformation on the equivalent Hamiltonian which reproduces the sequence of diagrams given by the random-phase approximation. The close resemblance of the general problem to the soluble model problem of a rotating dense electron gas is exploited in the calculation. This work extends that of Amado and Brueckner who have demonstrated only that interaction effects cancel in lowest order. The nature of their approximations and the connection to the problem of collective excitations are discussed.