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arXiv · 2312.06368

The Inertial Spin Model of flocking with position-dependent forces

Sebastián Carruitero·Alejo Costa Duran·Giulia Pisegna·Mauricio B. Sturla·Tomás S. Grigera
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Abstract

We propose an extension to the ISM of flocking and swarming. The model has been introduced to explain certain dynamic features of swarming (second sound, a lower than expected dynamic critical exponent) while preserving the mechanism for onset of order provided by the Vicsek model. The ISM has only been formulated with an imitation (``ferromagnetic'') interaction between velocities. Here we show how to add position-dependent forces in the model, which allows to consider effects such as cohesion, excluded volume, confinement and perturbation with external position-dependent field, and thus study this model without periodic boundary conditions. We study numerically a single particle with an harmonic confining field and compare it to a Brownian harmonic oscillator and to a harmonically confined active Browinian particle, finding qualitatively different behavior in the three cases.

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Sebastián Carruitero, Alejo Costa Duran, Giulia Pisegna, Mauricio B. Sturla, Tomás S. Grigera. 2023-12-11. The Inertial Spin Model of flocking with position-dependent forces. https://doi.org/10.1103/physreve.110.014408

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