2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/16032We consider the Ginzburg-Landau phase transition model with O(n) symmetry (i.e., the n-vector model) which includes a quenched randomness, i.e., a random temperature disorder. We have proven rigorously that within the diagrammatic perturbation theory the quenched randomness does not change the critical exponents at n tending to 0, which is in contrast to the conventional point of view based on the perturbative renormalization group theory.6 pages, no figuresStatistical Mechanicstext