The distribution of first digits in numbers series obtained from very different origins shows a marked asymmetry in favor of small digits that goes under the name of Benford's law. We analyze in detail this property for different data sets and give a general explanation for the origin of the...

The problem of classical diffusion in a random medium is mapped into a quantum mechanical problem with a disordered potential, and the dependence of the localization properties of the ground state wave function on the space dimensionality is analyzed. An extended ground state is obtained for D ...