A general approach to Lehmann-Suwa-Khanedani index theorems: partial holomorphic connections and extensions of foliations

This thesis stresses the strong link between the existence of partial holomorphic connections on the normal bundle of a foliation seen as a quotient of the ambient tangent bundle and the extendability of a foliation to an infinitesimal neighborhood of a submanifold. We find some obstructions to extendability and thanks to the theory developed we obtain some new Khanedani-Lehmann-Suwa type index theorems, for foliations and holomorphic self maps.