2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/101770This paper is withdrawn. While almost all findings reported here remain valid, some of our comments on the fate of weak localization corrections to the conductance in the deep semiclassical limit are now obsolete. Contrarily to what was suggested here, we find an exponential suppression of weak localization at finite Ehrenfest time. For more details, see cond-mat/0512662 .Mesoscale and Nanoscale PhysicsChaotic Dynamicstext