I will present a simple and (possibly) new method of organizing the (+/- cancellations in the) cluster expansions of polymer models, hard repulsion case. The method is suitable for models where polymers are "cycles" or closed paths in a lattice (Kramers-Wannier representation of the Ising model, perturbations of massless Gaussians) also in several cases where expansions are only nonabsolutely summable.
view more