Microscopic Expression of Anomalous Dissipation in Passive Scalar Transport

We study anomalous dissipation from a microscopic viewpoint. In the work by Drivas et al. (Arch Ration Mech Anal 243(3):1151–1180, 2022), the property of anomalous dissipation provides the existence of non-unique weak solutions for a transport equation with a singular velocity field. In this paper, we reconsider this solution in terms of kinetic theory and clarify its microscopic property. Consequently, energy loss can be expressed by non-vanishing microscopic obstruction.