Bosonic Monocluster Expansion
Résumé
We compute connected Green\'s functions of a Bosonic field theory with cutoffs by means of a ``minimal\'\' expansion which in a single move, interpolating a generalized propagator, performs the usual tasks of the cluster and Mayer expansion. In this way it allows a direct construction of the infinite volume or thermodynamic limit and it brings constructive Bosonic expansions closer to constructive Fermionic expansions and to perturbation theory.