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arXiv · 2410.14358

Noise-induced transitions from contractile to extensile active stress in isotropic fluids

Mathieu Dedenon·Karsten Kruse
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Abstract

Tissues of living cells are a prime example of active fluids. There is experimental evidence that tissues generate extensile active stress even though their constituting cells are contractile. Fluctuating forces that could result from cell-substrate interactions have been proposed to be able to induce a transition from contractile to extensile active stress. Through analytic calculations and numerical computations, we show that in isotropic active fluids, nonlinearities and a coupling between fluctuating forces and fluid density are necessary for such a transition to occur. Here, both transitions from extensile to contractile and vice versa are possible.

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BibTeXRIS

Mathieu Dedenon, Karsten Kruse. 2024-10-18. Noise-induced transitions from contractile to extensile active stress in isotropic fluids. https://doi.org/10.1103/physreve.111.015426

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