Abstract

We discuss diffeomorphism and gauge invariant theories in three dimensions, motivated by the fact that some models of interest do not have a suitable action description yet. The construction is based on a canonical representation of symmetry generators and on building of the corresponding canonical action. We obtain a class of theories whose number of local degrees of freedom depends on the dimension of the gauge group and the number of the independent constraints. By choosing the latter, we focus on three special cases, starting with a theory with the maximal local number of degrees of freedom and finishing with a theory with zero degrees of freedom (Chern-Simons).