  Langer theory of metastability provides a description of the lifetime and
properties of the metastable phase of the Ising model field-driven transition,
describing the magnetic field-driven transition in ferromagnets and the
chemical potential-driven transition of fluids. An immediate further step is to
apply it to the study of a transition driven by the temperature, as the one
underwent by the two-dimensional Potts model. For this model a study based on
the analytical continuation of the free energy (Meunier, Morel 2000) predicts
the anomalous vanishing of the metastable temperature range in the limit of
large system size, an issue that has been controversial since the eighties.
With a parallel-GPU algorithm we compare the Monte Carlo dynamics with the
theory, obtaining agreement and characterizing the anomalous system size
dependence. We discuss the microscopic origin of these metastable phenomena,
essentially different with respect to the Ising case.
