Revisiting the flocking transition using active spins.

@article{Solon2013RevisitingTF,
  title={Revisiting the flocking transition using active spins.},
  author={Alexandre Solon and Julien Tailleur},
  journal={Physical review letters},
  year={2013},
  volume={111 7},
  pages={
          078101
        }
}
We consider an active Ising model in which spins both diffuse and align on lattice in one and two dimensions. The diffusion is biased so that plus or minus spins hop preferably to the left or to the right, which generates a flocking transition at low temperature and high density. We construct a coarse-grained description of the model that predicts this transition to be a first-order liquid-gas transition in the temperature-density ensemble, with a critical density sent to infinity. In this… 

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