2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/90538By defining information entropy in terms of probabilities densities $|Ψ|^2$ ($Ψ$ is a wave function in the coordinate representation) it is explicitly shown how a loss of quantum information occurs in a transition from a quantum to a quasi-classical regime.Some residual typos are correctedQuantum Physicstext