Supercurrents as Eulerian Fluids

Macroscopic equations of hydrodynamics can be associated with rigid superconductors through a time-dependent Schroedinger-Ginzburg-Landau equation,as suggested by Froelich. Here, this issue is re-proposed in a slightly revised different approach and derived from a Lagrangian, through a variational procedure. Interesting novel aspects of the hydrodynamic equations for supercurrents are shown in evidence. Also, Lagrangian variables are inroduced and the equations of interest are written in these variables in view of an extension to deformable bodies.