Hydrodynamic Formulation of the Hubbard Model
  In this article, we show how to recast the Hubbard model in one dimension in a hydrodynamic language and use the path integral approach to compute the one-particle Green function.   We compare with the Bethe ansatz results of   Schulz and find exact agreement with the formulas for spin and charge velocities and anomalous exponent in weak coupling regime.   These methods may be naturally generalized to more than one dimension by simply promoting wavenumbers to wavevectors. 
Girish S. Setlur (HRI, Allahabad)