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arXiv · 1008.2323

Renewal-anomalous-heterogeneous files

Ophir Flomenbom
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Abstract

Renewal-anomalous-heterogeneous files are solved. A simple file is made of Brownian hard spheres that diffuse stochastically in an effective 1D channel. Generally, Brownian files are heterogeneous: the spheres' diffusion coefficients are distributed and the initial spheres' density is non-uniform. In renewal-anomalous files, the distribution of waiting times for individual jumps is exponential as in Brownian files, yet obeys: {\psi}_{\alpha} (t)~t^(-1-{\alpha}), 0<{\alpha}<1. The file is renewal as all the particles attempt to jump at the same time. It is shown that the mean square displacement (MSD) in a renewal-anomalous-heterogeneous file, , obeys, ~[ _{nrml}]^{\alpha}, where _{nrml} is the MSD in the corresponding Brownian file. This scaling is an outcome of an exact relation (derived here) connecting probability density functions of Brownian files and renewal-anomalous files. It is also shown that non-renewal-anomalous files are slower than the corresponding renewal ones.

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Ophir Flomenbom. 2010-08-13. Renewal-anomalous-heterogeneous files. https://doi.org/10.1016/j.physleta.2010.08.029

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