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arXiv · 2002.06950

Motile dissenters disrupt the flocking of active granular matter

Pradip K. Bera·A. K. Sood
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Abstract

We report flocking in the dry active granular matter of millimeter-sized two-step-tapered rods without an intervening medium. The system undergoes the flocking phase transition at a threshold area fraction ~ 0.12 having high orientational correlations between the particles. However, the one-step-tapered rods do not flock and are used as the motile dissenters in the flock-forming granular matter. At the critical fraction of dissenters ~ 0.3, the flocking order of the system gets completely destroyed. The variance of the system's order parameter shows a maximum near the dissenter fraction f ~ 0.05, suggesting a finite-size crossover between the ordered and disordered phases.

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Pradip K. Bera, A. K. Sood. 2020-02-17. Motile dissenters disrupt the flocking of active granular matter. https://doi.org/10.1103/physreve.101.052615

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