  We construct, by a procedure involving a dimensional reduction from a
Chern-Simons theory with borders, an effective theory for a 1+1 dimensional
superconductor. 1That system can be either in an ordinary phase or in a
topological one, depending on the value of two phases, corresponding to complex
order parameters. Finally, we argue that the original theory and its
dimensionally reduced one can be related to the effective action for a quantum
Dirac field in a slab geometry, coupled to a gauge field.
