2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/217494We 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.5 pages including 6 postscript figures. Talk given at HEP01 in Budapest, Hungary, in July 2001High Energy Physics - Latticetext