Chern-Simons field theory and invariants of 3-manifolds

In the last decade the research field under the name of topological quantum field theory has undergone an impressive growth. We shall focus our attention on the topological quantum field theory introduced by Witten, namely the 3-dimensional Chern-Simons field theory. Differently from Witten's original approach, we shall adopt a fully 3-dimensional point of view; no result from 2-dimensional conformal field theory will be used.