Vortices and gauge fields in the pseudospin model of liquid 4He

We show that below the lambda point a microscopic (pseudospin) model of liquid 4He, that incorporates hard-core repulsion and nearest-neighbour attraction between atoms, is equivalent to a Gross-Pitaevskii (GP) model of weakly interacting (soft-core) bosons in the presence of a self-generated gauge field, by specializing to cylindrically symmetric vortex solutions. Requiring consistency in the behaviour of the condensate density in the two models, we are able to identify the gauge field in the GP model as that part of the total velocity that has a non-vanishing curl in the pseudospin model. It becomes evident that the gauge field is the depletion velocity. (author)