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  • Open Access

New Universality Class Describes Vicsek’s Flocking Phase in Physical Dimensions

Patrick Jentsch and Chiu Fan Lee*

  • *Contact author: c.lee@imperial.ac.uk
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Phys. Rev. Lett. 133, 128301 – Published 17 September, 2024

DOI: https://doi.org/10.1103/PhysRevLett.133.128301

Abstract

The Vicsek simulation model of flocking together with its theoretical treatment by Toner and Tu in 1995 were two foundational cornerstones of active matter physics. However, despite the field’s tremendous progress, the actual universality class (UC) governing the scaling behavior of Viscek’s “flocking” phase remains elusive. Here, we use nonperturbative, functional renormalization group methods to analyze, numerically and analytically, a simplified version of the Toner-Tu model, and uncover a novel UC with scaling exponents that agree remarkably well with the values obtained in a recent simulation study by Mahault et al. [Phys. Rev. Lett. 123, 218001 (2019)], in both two and three spatial dimensions. We therefore believe that there is strong evidence that the UC uncovered here describes Vicsek’s flocking phase.

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References (51)

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Phys. Rev. Lett. 133, 128301– Published 17 September, 2024
  • Received 4 March 2024
  • Accepted 5 August 2024
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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