Softness, anomalous dynamics, and fractal-like energy landscape in model cell tissues

Yan-Wei Li; Leon Loh Yeong Wei; Matteo Paoluzzi; Massimo Pica Ciamarra

doi:10.1103/physreve.103.022607

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arXiv · 2101.09120

Softness, anomalous dynamics, and fractal-like energy landscape in model cell tissues

Yan-Wei Li·Leon Loh Yeong Wei·Matteo Paoluzzi·Massimo Pica Ciamarra

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Abstract

Epithelial cell tissues have a slow relaxation dynamics resembling that of supercooled liquids. Yet, they also have distinguishing features. These include an extended short-time sub-diffusive transient, as observed in some experiments and recent studies of model systems, and a sub-Arrhenius dependence of the relaxation time on temperature, as reported in numerical studies. Here we demonstrate that the anomalous glassy dynamics of epithelial tissues originates from the emergence of a fractal-like energy landscape, particles becoming virtually free to diffuse in specific phase space directions up to a small distance. Furthermore, we clarify that the stiffness of the cells tunes this anomalous behaviour, tissues of stiff cells having conventional glassy relaxation dynamics.

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Yan-Wei Li, Leon Loh Yeong Wei, Matteo Paoluzzi, Massimo Pica Ciamarra. 2021-01-22. Softness, anomalous dynamics, and fractal-like energy landscape in model cell tissues. https://doi.org/10.1103/physreve.103.022607

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