2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/18324We introduce phase space concepts to describe quantum states in a disordered system. The merits of an inverse participation ratio defined on the basis of the Husimi function are demonstrated by a numerical study of the Anderson model in one, two, and three dimensions. Contrary to the inverse participation ratios in real and momentum space, the corresponding phase space quantity allows for a distinction between the ballistic, diffusive, and localized regimes on a unique footing and provides valuable insight into the structure of the eigenstates.4 pages, 3 figures, RevTeX4Disordered Systems and Neural Networkstext