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arXiv · 2306.01156

Metastability of Discrete-Symmetry Flocks

Brieuc Benvegnen·Omer Granek·Sunghan Ro·Ran Yaacoby·Hugues Chaté·Yariv Kafri·David Mukamel·Alexandre Solon·Julien Tailleur
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Abstract

We study the stability of the ordered phase of flocking models with a scalar order parameter. Using both the active Ising model and a hydrodynamic description, we show that droplets of particles moving in the direction opposite to that of the ordered phase nucleate and grow. We characterize analytically this self-similar growth and demonstrate that droplets spread ballistically in all directions. Our results imply that, in the thermodynamic limit, discrete-symmetry flocks -- and, by extension, continuous-symmetry flocks with rotational anisotropy -- are metastable in all dimensions.

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Brieuc Benvegnen, Omer Granek, Sunghan Ro, Ran Yaacoby, Hugues Chaté, Yariv Kafri, David Mukamel, Alexandre Solon, Julien Tailleur. 2023-06-01. Metastability of Discrete-Symmetry Flocks. https://doi.org/10.1103/physrevlett.131.218301

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