  An interlayer phase coherence develops spontaneously in the bilayer quantum
Hall system at the filling factor $\nu =1$. On the other hand, the spin and
pseudospin degrees of freedom are entangled coherently in the canted
antiferromagnetic phase of the bilayer quantum Hall system at the filling
factor $\nu =2$. There emerges a complex Nambu-Goldstone mode with a linear
dispersion in the zero tunneling-interaction limit for both cases. Then its
phase field provokes a Josephson supercurrent in each layer, which is
dissipationless as in a superconductor. We study what kind of phase coherence
the Nambu-Goldstone mode develops in association with the Josephson
supercurrent and its effect on the Hall resistance in the bilayer quantum Hall
system at $\nu=1,2$, by employing the Grassmannian formalism.
