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Direct Numerical Observation of Anomalous Diffusion in Random Media

Victor Pham·Michael W. Deem
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Abstract

We present computer simulations of anomalous diffusion, $< r^2(t) > \sim a t^{1-δ}$, in two dimensions. The Monte Carlo calculations are in excellent agreement with previous renormalization group calculations. Interestingly, use of a high quality pseudo-random number generator is necessary to observe the anomalous diffusion. A linear-feedback, shift-register method leads to incorrect, ballistic motion of the random walkers.

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Victor Pham, Michael W. Deem. 1998-08-03. Direct Numerical Observation of Anomalous Diffusion in Random Media. https://doi.org/10.1088/0305-4470%2F31%2F35%2F005

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