Aspects of the density field in an active nematic

Shradha Mishra; Sanjay Puri; Sriram Ramaswamy

doi:10.1098/rsta.2013.0364

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arXiv · 1410.5589

Aspects of the density field in an active nematic

Shradha Mishra·Sanjay Puri·Sriram Ramaswamy

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Abstract

Active nematics are conceptually the simplest orientationally ordered phase of self-driven particles, but have proved to be a perennial source of surprises. We show here through numerical solution of coarse-grained equations for order parameter and density that the growth of the active nematic phase from the isotropic phase is necessarily accompanied by a clumping of the density. The growth kinetics of the density domains is shown to be faster than the 1/3-law expected for variables governed by a conservation law. Other results presented include the suppression of density fluctuations in the stationary ordered nematic by the imposition of an orienting field. We close by posing some open questions.

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Shradha Mishra, Sanjay Puri, Sriram Ramaswamy. 2014-10-21. Aspects of the density field in an active nematic. https://doi.org/10.1098/rsta.2013.0364

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