2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/18982We present the effective theory for low energy dynamics of a two-dimensional interacting electrons in the presence of a weak short-range disorder and a weak perpendicular magnetic field, the filling factor $ν\gg 1$. We investigate the exchange enhancement of the $g$-factor, the effective mass and the decay rate of the simplest spin wave excitations at $ν= 2 N + 1$. We obtain the enhancement of the field-induced gap in the tunneling density of states and dependence of the tunneling conductivity on the applied bias.17 pages, no figuresMesoscale and Nanoscale Physicstext