2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/184480We show that Green functions of second-order differential operators with singular or unbounded coefficients can have an anomalous behaviour in comparison to the well-known properties of Green functions of operators with bounded coefficients. We discuss some consequences of such an anomalous short or long distance behaviour for a diffusion and wave propagation in an inhomogeneous medium.High Energy Physics - Theorytext