2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/227222We study the perturbative behaviour of topological black holes. We calculate both analytically and numerically the quasi-normal modes of scalar perturbations. In the case of small black holes we find discontinuities of the quasi-normal modes spectrum at the critical temperature and we argue that this is evidence of a second-order phase transition.23 pages, 17 figures, published versionHigh Energy Physics - TheoryAstrophysicsGeneral Relativity and Quantum Cosmologytext