Anomalous physical transport in complex networks

The emergence of scaling in transport through interconnected systems is a consequence of the topological structure of the network and the physical mechanisms underlying the transport dynamics. We study transport by advection and diffusion in scale-free and Erd\ifmmode \mbox{\H{o}}\else \H{o}\fi{}s-R\'enyi networks. Velocity distributions derived from a flow potential exhibit power-law scaling with exponent $\ensuremath{\nu}\ensuremath{\approx}\ensuremath{\gamma}+1$, where $\ensuremath{\gamma}$ is the exponent of network connectivity. Using stochastic particle simulations, we find anomalous (nonlinear) scaling of the mean-square displacement with time. We show the connection with existing descriptions of anomalous transport in disordered systems, and explain the mean transport behavior from the coupled nature of particle jump lengths and transition times.