  We investigate the Hubbard model in the limit $U=\infty$, which is equivalent
to the statistical condition of exclusion of double occupancy. We solve this
problem using Dirac's method for constraints. The constraints are solved within
the Bosonization method. We find that the constraints modify the anomalous
commutator.
  We apply this theory to quantum wires at finite temperatures where the
Hubbard interaction is $U=\infty$. We find that the anomalous commutator
induced by the constraints gives rise to the 0.7 anomalous conductance.
