Field-dependent symmetries of a non-relativistic fluid model

As found by Bordemann and Hoppe and by Jevicki, a certain non-relativistic model of an irrotational and isentropic fluid, related to membranes and to partons, admits a Poincar\'e symmetry. Bazeia and Jackiw associate this dynamical symmetry to a novel type of ``field dependent'' action on space-time. The ``Kaluza-Klein type'' framework of Duval et al. is used to explain the origin of these symmetries and to derive the associated conserved quantities. In the non-interacting case, the symmetry extends to the entire conformal group.