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arXiv · 2105.07872

Anomalous diffusion and Lévy walks distinguish active from inertial turbulence

Siddhartha Mukherjee·Rahul K. Singh·Martin James·Samriddhi Sankar Ray
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Abstract

Bacterial swarms display intriguing dynamical states like active turbulence. Using a hydrodynamic model we now show that such dense active suspensions manifest super-diffusion, via Lévy walks, which masquerades as a crossover from ballistic to diffusive scaling in measurements of mean-squared-displacements, and is tied to the emergence of hitherto undetected oscillatory streaks in the flow. Thus, while laying the theoretical framework of an emergent advantageous strategy in the collective behaviour of microorganisms, our study underlines the essential differences between active and inertial turbulence.

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Siddhartha Mukherjee, Rahul K. Singh, Martin James, Samriddhi Sankar Ray. 2021-09-13. Anomalous diffusion and Lévy walks distinguish active from inertial turbulence. https://doi.org/10.1103/physrevlett.127.118001

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