2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/28508We employ Wiegmann's solution of the Anderson impurity model in order to compute the compressibility of electron gas. We have found that there is a pair of neighbor levels separated by anomalously large energy $\propto L^{-1/3}$, where $L$ is the size of the system. The Fermi energy crosses this pseudogap and the compressibility decreases near the so-called ``symmetric'' limit.2 pages, twocolumnCondensed Mattertext