Superfluid Flow and Analogy to Dirac's Monopole

Abstract

Taking the depletion effect into consideration in terms of the depletion velocity, superfluid flow in an annulus is discussed. It is shown that in annular regions superfluid flow is the gauge-invariant manifestation of a nonintegrable phase factor. The circulation is defined in terms of the depletion velocity which is essentially rotational. Arguments akin to Dirac's theory of magnetic monopole are used to obtain quantum mechanical vortex lines which have their ends in fluid.