We consider the ferromagnetic q-state Potts model with zero external field in
a finite volume evolving according to Glauber-type dynamics described by the
Metropolis algorithm in the low temperature asymptotic limit. Our analysis
concerns the multi-spin system that has q stable equilibria. Focusing on grid
graphs with periodic boundary conditions, we study the tunneling between two
stable states and from one stable state to the set of all other stable states.
In both cases we identify the set of gates for the transition and prove that
this set has to be crossed with high probability during the transition.
Moreover, we identify the tube of typical paths and prove that the probability
to deviate from it during the transition is exponentially small.Comment: 44 pages, 15 figures. All comments are welcome