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Understanding Anomalous Transport in Intermittent Maps: From Continuous Time Random Walks to Fractals

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 نشر من قبل Korabel
 تاريخ النشر 2004
  مجال البحث فيزياء
والبحث باللغة English
 تأليف N. Korabel




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We show that the generalized diffusion coefficient of a subdiffusive intermittent map is a fractal function of control parameters. A modified continuous time random walk theory yields its coarse functional form and correctly describes a dynamical phase transition from normal to anomalous diffusion marked by strong suppression of diffusion. Similarly, the probability density of moving particles is governed by a time-fractional diffusion equation on coarse scales while exhibiting a specific fine structure. Approximations beyond stochastic theory are derived from a generalized Taylor-Green-Kubo formula.



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