Quantitative Assessment of the Toner and Tu Theory of Polar Flocks.

We present a quantitative assessment of the Toner and Tu theory describing the universal scaling of fluctuations in polar phases of dry active matter. Using large-scale simulations of the Vicsek model in two and three dimensions, we find the overall phenomenology and generic algebraic scaling predicted by Toner and Tu, but our data on density correlations reveal some qualitative discrepancies. The values of the associated scaling exponents we estimate differ significantly from those conjectured in 1995. In particular, we identify a large crossover scale beyond which flocks are only weakly anisotropic. We discuss the meaning and consequences of these results.

• Publication year

  2019

• Venue

  Physical Review Letters

• Publication date

  2019-08-10

• Fields of study

  Medicine, Physics

• Identifiers
  DOI 10.1103/PhysRevLett.123.218001arXiv 1908.03794PMID 31809144
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar, PubMed

• No claims are published for this paper.

• No concepts are published for this paper.

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