Donaldson-Witten invariants and pure 4D QCD with order and disorder ʹt Hooft-like operators

In this paper we study the first-order formalism of pure four-dimensional SU(2) Yang-Mills theory with theta-term. We describe the Green functions associated to the electric and magnetic flux operators à la ʹt Hooft, by means of gauge-invariant non-local operators. These Green functions are related to Wittenʹs invariants of four-manifolds.