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Self-reinforcing directionality generates Levy walks without the power-law assumption

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 نشر من قبل Daniel Han Mr.
 تاريخ النشر 2020
  مجال البحث فيزياء علم الأحياء
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We introduce a persistent random walk model with finite velocity and self-reinforcing directionality, which explains how exponentially distributed runs self-organize into truncated Levy walks observed in active intracellular transport by Chen et. al. [textit{Nat. mat.}, 2015]. We derive the non-homogeneous in space and time, hyperbolic PDE for the probability density function (PDF) of particle position. This PDF exhibits a bimodal density (aggregation phenomena) in the superdiffusive regime, which is not observed in classical linear hyperbolic and Levy walk models. We find the exact solutions for the first and second moments and criteria for the transition to superdiffusion.



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