Duality and Regge trajectories in the 2D Potts model on square lattice.
Marco Astorino, Fabrizio Canfora
Abstract
A unified approach to the ferromagnetic two dimensional Potts model on square lattice is proposed. The compatibility with the still to be found solutions of the three (and higher) dimensional Ising model allows one to write down an explicit analytic ansatz for the free energy in terms of few q-dependent Regge trajectories. The duality symmetry of the 2D Potts model together with the known results on its critical exponent α allow to fix a priori in an analytic way all but one Regge trajectory. The agreement of proposed analytic ansatz with Monte Carlo data and observations in the q = 3 case is remarkable in all the range of temperatures. It is shown that the q> 4 cases naturally fit into the same scheme and that one should also expect a good agreement with Monte Carlo data and observations. The limiting q = 4 case is shortly discussed.