  A single-sided boundary is introduced in the three-dimensional Chern-Simons
model. It is shown that only one boundary condition for the gauge fields is
possible, which plays the twofold role of chirality condition and bosonization
rule for the two-dimensional Weyl fermion describing the degrees of freedom of
the edge states of the Fractional Quantum Hall Effect. It is derived the
symmetry on the boundary which determines the effective two dimensional action,
whose equation of motion coincides with the continuity equation of the
Tomonaga-Luttinger theory. The role of Lorentz symmetry and of discrete
symmetries on the boundary is also discussed.
