One motivation of the study of active matter by physicist is the rich phenomenology associated to this field. Collective motion and swarming are among the most studied phenomena. Within the huge number of models that have been developed to catch such behavior from a microscopic description, the most famous is the so-called Vicsek model introduced by Tamás Vicsek et al. in 1995. (From Wikipedia)

Simulation data
    - Number of particles: 32768
    - Number of cells: 1000000
    - Distance r: 0.01
    - Cell size (x,y,z): (0.01, 0.01, 0.01)
    - Domain: [0,1]x[0,1]x[0,1]
    - Periodic boundary conditions (PBCs)
    - Noise: normal distribution with  mean value 0 and standard deviation 0.1
    - time step: 0.0005

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