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arXiv · 2112.00667

Lagrangian Manifestation of Anomalies in Active Turbulence

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

We show that Lagrangian measurements in active turbulence bear imprints of turbulent and anomalous streaky hydrodynamics leading to a self-selection of persistent trajectories - Levy walks - over diffusive ones. This emergent dynamical heterogeneity results in a super-diffusive first passage distribution which could lead to biologically advantageous motility. We then go beyond single-particle statistics to show that for the pair-dispersion problem as well, active flows are at odds with inertial turbulence. Our study, we believe, will readily inform experiments in establishing the extent of universality of anomalous behaviour across a variety of active flows.

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Rahul K. Singh, Siddhartha Mukherjee, Samriddhi Sankar Ray. 2022-08-25. Lagrangian Manifestation of Anomalies in Active Turbulence. https://doi.org/10.1103/physrevfluids.7.033101

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