We consider a two-dimensional σ-model with discrete
icosahedral/dodecahedral symmetry. Using the perturbative renormalization
group, we argue that this model has a different continuum limit with respect to
the O(3) σ model. Such an argument is confirmed by a high-precision
numerical simulation.Comment: 5 pages including 6 postscript figures. Talk given at HEP01 in
Budapest, Hungary, in July 200