Anomalous diffusion and response in branched systems: a simple analysis

  title={Anomalous diffusion and response in branched systems: a simple analysis},
  author={Giuseppe Forte and Raffaella Burioni and Fabio Cecconi and Angelo Vulpiani},
  journal={Journal of Physics: Condensed Matter},
We revisit the diffusion properties and the mean drift induced by an external field of a random walk process in a class of branched structures, as the comb lattice and the linear chains of plaquettes. A simple treatment based on scaling arguments is able to predict the correct anomalous regime for different topologies. In addition, we show that even in the presence of anomalous diffusion, Einstein’s relation still holds, implying a proportionality between the mean square displacement of the… 

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