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Minimal model for active nematics: quasi-long-range order and giant fluctuations

Hugues Chate·Francesco Ginelli·Raul Montagne
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Abstract

We propose a minimal microscopic model for active nematic particles similar in spirit to the Vicsek model for self-propelled polar particles. In two dimensions, we show that this model exhibits a Kosterlitz-Thouless-like transition to quasi-long-range orientational order and that in this non-equilibrium context, the ordered phase is characterized by giant density fluctuations, in agreement with the predictions of Ramaswamy {\it et al.} [Europhys. Lett. {\bf 62}, 196 (2003)].

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Hugues Chate, Francesco Ginelli, Raul Montagne. 2006-03-03. Minimal model for active nematics: quasi-long-range order and giant fluctuations. https://doi.org/10.1103/physrevlett.96.180602

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