Potts Models with Invisible States
Des Johnston (Heriot-Watt University)
Tuesday 3rd December, 2013 15:00-16:00 Maths 515
The order of a phase transition in statistical mechanical models is usually determined by the nature of the symmetry breaking at the phase transition point and the dimension of the model under consideration.
Motivated by several systems which didn't appear to possess the expected transition order, Tamura et al recently introduced Potts models with ‘invisible’ states which contribute to the entropy but not the internal energy. They noted that adding such invisible states could transmute continuous transitions into first order transitions.
We discuss the use of several mean-field techniques to investigate the phase diagram, and the mechanism for transmuting the phase transition, in such invisible state Potts models.