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arXiv · 2306.03695

Dynamics of Ordered Active Columns: Flows, Twists, and Waves

S. J. Kole·Gareth P. Alexander·Ananyo Maitra·Sriram Ramaswamy
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Abstract

We formulate the hydrodynamics of active columnar phases, with two-dimensional translational order in the plane perpendicular to the columns and no elastic restoring force for relative sliding of the columns, using the general formalism of an active model H$^*$. Our predictions include: two-dimensional odd elasticity coming from three-dimensional plasmon-like oscillations of the columns in chiral polar phases with a frequency that is independent of wavenumber and non-analytic; a buckling instability coming from the generic force-dipole active stress analogous to the mechanical Helfrich-Hurault instability in passive materials; the selection of helical column undulations by apolar chiral activity.

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S. J. Kole, Gareth P. Alexander, Ananyo Maitra, Sriram Ramaswamy. 2023-06-06. Dynamics of Ordered Active Columns: Flows, Twists, and Waves. https://arxiv.org/abs/2306.03695

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