The CPN−1 model: A strong coupling lattice approach

We develop large N character-like expansion techniques for vector and vector-like models. These are used to compute the mass gaps and beta functions in the d = 2 CP^N?1 models. Surprisingly there is an intermediate region where neither strong coupling nor perturbation theory is applicable. This “unknown” region is a consequence of the non-commutativity of strong coupling and large N, an interesting mathematical effect not found in other models and due to an interesting physical phenomenon: superconfinement.