Short-range interactions versus long-range correlations in bird flocks.

@article{Cavagna2015ShortrangeIV,
  title={Short-range interactions versus long-range correlations in bird flocks.},
  author={Andrea Cavagna and Lorenzo Del Castello and Supravat Dey and Irene Giardina and Stefania Melillo and Leonardo Parisi and Massimiliano Viale},
  journal={Physical review. E, Statistical, nonlinear, and soft matter physics},
  year={2015},
  volume={92 1},
  pages={
          012705
        }
}
Bird flocks are a paradigmatic example of collective motion. One of the prominent traits of flocking is the presence of long range velocity correlations between individuals, which allow them to influence each other over the large scales, keeping a high level of group coordination. A crucial question is to understand what is the mutual interaction between birds generating such nontrivial correlations. Here we use the maximum entropy (ME) approach to infer from experimental data of natural flocks… 

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