A Hydrodynamic Approach to Superconductivity
  Recently Tsai et.al. (cond-mat/0406174) have used the renormalization group approach to study strong coupling superconductors without assuming a broken symmetry phase. We use the hydrodynamic formulation to study the same problem with the same intention.   We recast the electron-phonon + electron-electron problem in the hydrodynamic language and compute the one-particle electron Green function at finite temperature.   From this we extract the dynamical density of states at finite temperature and look for sign of a gap. 
Girish S. Setlur