Variational approach for the N-state spin and gauge Potts model

Abstract

A hamiltonian variational treatment is applied both to the spin Potts model and to its gauge version for any number of states N and spatial dimensions d>2. Regarding the former we reproduce the correct critical coupling and latent heat for not too low N and d. For the latter, our approach turns the gauge theory into an equivalent ¿-dimensional classical spin model, which evaluated for d + 1' = 4 gives results in agreement with 1 / N expansions.