Onset of collective and cohesive motion

G Gregoire; H Chate

doi:10.1103/physrevlett.92.025702

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Onset of collective and cohesive motion

G Gregoire·H Chate

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Abstract

We study the onset of collective motion, with and without cohesion, of groups of noisy self-propelled particles interacting locally. We find that this phase transition, in two space dimensions, is always discontinuous, including for the minimal model of Vicsek et al. [Phys. Rev. Lett. {\bf 75},1226 (1995)] for which a non-trivial critical point was previously advocated. We also show that cohesion is always lost near onset, as a result of the interplay of density, velocity, and shape fluctuations.

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G Gregoire, H Chate. 2004-01-13. Onset of collective and cohesive motion. https://doi.org/10.1103/physrevlett.92.025702

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