Spatial log-periodic oscillations of first-passage observables in fractals

Phys Rev E Stat Nonlin Soft Matter Phys. 2012 Dec;86(6 Pt 1):061125. doi: 10.1103/PhysRevE.86.061125. Epub 2012 Dec 18.

Abstract

For transport processes in geometrically restricted domains, the mean first-passage time (MFPT) admits a general scaling dependence on space parameters for diffusion, anomalous diffusion, and diffusion in disordered or fractal media. For transport in self-similar fractal structures, we obtain an expression for the source-target distance dependence of the MFPT that exhibits both the leading power-law behavior, depending on the Hausdorff and spectral dimension of the fractal, as well as small log-periodic oscillations that are a clear and definitive signal of the underlying fractal structure. We also present refined numerical results for the Sierpinski gasket that confirm this oscillatory behavior.