Clustering and anisotropic correlated percolation in polar flocks

Nikos Kyriakopoulos; Hugues Chaté; Francesco Ginelli

doi:10.1103/physreve.100.022606

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arXiv · 1905.12021

Clustering and anisotropic correlated percolation in polar flocks

Nikos Kyriakopoulos·Hugues Chaté·Francesco Ginelli

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Abstract

We study clustering and percolation phenomena in the Vicsek model, taken here in its capacity of prototypical model for dry aligning active matter. Our results show that the order-disorder transition is not related in any way to a percolation transition, contrary to some earlier claims. We study geometric percolation in each of the phases at play, but we mostly focus on the ordered Toner-Tu phase, where we find that the long-range correlations of density fluctuations give rise to a novel anisotropic percolation transition.

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Nikos Kyriakopoulos, Hugues Chaté, Francesco Ginelli. 2019-05-28. Clustering and anisotropic correlated percolation in polar flocks. https://doi.org/10.1103/physreve.100.022606

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