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arXiv · 1206.2901

Criticality and the Onset of Ordering in the Standard Vicsek Model

Gabriel Baglietto·Ezequiel V. Albano·Julián Candia
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Abstract

Experimental observations of animal collective behavior have shown stunning evidence for the emergence of large-scale cooperative phenomena resembling phase transitions in physical systems. Indeed, quantitative studies have found scale-free correlations and critical behavior consistent with the occurrence of continuous, second-order phase transitions. The Standard Vicsek Model (SVM), a minimal model of self-propelled particles in which their tendency to align with each other competes with perturbations controlled by a noise term, appears to capture the essential ingredients of critical flocking phenomena. In this paper, we review recent finite-size scaling and dynamical studies of the SVM, which present a full characterization of the continuous phase transition through dynamical and critical exponents. We also present a complex network analysis of SVM flocks and discuss the onset of ordering in connection with XY-like spin models.

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Gabriel Baglietto, Ezequiel V. Albano, Julián Candia. 2012-06-13. Criticality and the Onset of Ordering in the Standard Vicsek Model. https://doi.org/10.1098/rsfs.2012.0021

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