2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/56348I review recent results on conformal field theories in four dimensions and quantum field theories interpolating between conformal fixed points, supersymmetric and non-supersymmetric. The talk is structured in three parts: i) central charges, ii) anomalous dimensions and iii) quantum irreversibility.Talk given at the XIV International Workshop on High Energy Physics and Quantum Field Theory, Moscow, June, 1999. 9 pagesHigh Energy Physics - TheoryHigh Energy Physics - Phenomenologytext