2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/16338In the wake of a new kind of phase generally occurring in mesoscopic transport phenomena, we discuss the validity of Friedel sum rule in the presence of this phase. We find that the general Friedel sum rule may be violated.Some crucial typos correctedMesoscale and Nanoscale Physicstext