2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/171746We extend our sum over topologies formula to fermions. We show that fermionic fields display an instability with respect to topology fluctuations. We present some phenomenological arguments for a modification of the action in the case of fermions and discuss possible applications.High Energy Physics - TheoryInstability of fermions with respect to topology fluctuationstext