FERMIONIC COSET MODELS AS TOPOLOGICAL MODELS

By considering the fermionic realization of G/H coset models, we show that the partition function for the U(1)/U(1) model defines a topologi cal quantum field theory and coincides with that of a two-dimensional Abelian BF system. In the non-Abelian case, we prove the topological c haracter of G/G coset models by explicit computation, also finding a n atural extension of two-dimensional BF systems with non-Abelian symmet ry.