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arXiv · 2205.05619

Force generation in confined active fluids: The role of microstructure

Shuvojit Paul·Ashreya Jayaram·N Narinder·Thomas Speck·Clemens Bechinger
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Abstract

We experimentally determine the force exerted by a bath of active particles onto a passive probe as a function of its distance to a wall and compare it to the measured averaged density distribution of active particles around the probe. Within the framework of an active stress, we demonstrate that both quantities are - up to a factor - directly related to each other. Our results are in excellent agreement with a minimal numerical model and confirm a general and system-independent relationship between the microstructure of active particles and transmitted forces.

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Shuvojit Paul, Ashreya Jayaram, N Narinder, Thomas Speck, Clemens Bechinger. 2022-05-11. Force generation in confined active fluids: The role of microstructure. https://doi.org/10.1103/physrevlett.129.058001

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