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Renewal-anomalous-heterogeneous files

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 Added by Ophir Flomenbom
 Publication date 2010
  fields Physics Biology
and research's language is English




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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, <r^2>, obeys, <r^2>~[<r^2>_{nrml}]^{alpha}, where <r^2 >_{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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