Transport theory is reinvestigated in a one-particle model including dissipation
mechanisms through a phenomenological time-dependent part. Using the
description of an aperiodic crystal in terms of noncommutative geometry, it is
then possible to rigorously derive Kubo formulas for the electric conductivity.
Within the framework of the relaxation time approximation, a fractal analysis
applied to the spectral measures entering in the Kubo formula allows us to
examine anomalous transport owing to quantum interferences. This leads to
anomalies in Drude's formula