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arXiv · 1607.00493

Tracer Particles in Two-Dimensional Elastic Networks Diffuse Logarithmically Slow

Ludvig Lizana·Tobias Ambjörnsson·Michael A. Lomholt
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Abstract

Several experiments on tagged molecules or particles in living systems suggest that they move anomalously slow - their mean squared displacement (MSD) increase slower than linearly with time. Leading models aimed at understanding these experiments predict that the MSD grows as a power law with a growth exponent that is smaller than unity. However, in some experiments the exponent is so small $(\sim 0.1-0.2)$ that they hint towards other mechanisms at play. In this paper, we theoretically demonstrate how in-plane collective modes excited by thermal fluctuations in a two dimensional membrane lead to logarithmic time dependence for the mean square displacement of a tracer particle.

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Ludvig Lizana, Tobias Ambjörnsson, Michael A. Lomholt. 2016-07-02. Tracer Particles in Two-Dimensional Elastic Networks Diffuse Logarithmically Slow. https://doi.org/10.1088/1751-8121%2F50%2F3%2F034001

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