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arXiv · 1410.2764

Critical Phenomenon of the Order-Disorder Transition in Incompressible Flocks

Leiming Chen·John Toner·Chiu Fan Lee
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Abstract

We study incompressible systems of motile particles with alignment interactions. Unlike their compressible counterparts, in which the order-disorder (i.e., moving to static) transition, tuned by either noise or number density, is discontinuous, in incompressible systems this transition can be continuous, and belongs to a new universality class. We calculate the critical exponents to $O(\epsilon)$in an $\epsilon=4-d$ expansion, and derive two exact scaling relations. This is the first analytic treatment of a phase transition in a new universality class in an active system.

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Leiming Chen, John Toner, Chiu Fan Lee. 2014-10-10. Critical Phenomenon of the Order-Disorder Transition in Incompressible Flocks. https://doi.org/10.1088/1367-2630/17/4/042002

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