On the New Model of Non-Fermi Liquid for High Temperature   Superconductivity
  The importance of introducing the SO(5) singlet into the new novel model of non-Fermi liquid proposed by LeClair and collaborators is pointed out. This SO(5) singlet order parameter leads to a phase transition between the normal metal and the pseudogap region in the phase diagram for the anti-ferromagnetic (AF) phase and the (d-wave) superconducting (SC) phase. A non-zero value for this order can increase substantially the critical temperature of the SC transition. 
S.-H. Henry Tye