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arXiv · 2512.17035

The Vicsek-Kuramoto model in collective dynamics: macroscopic equations and pattern formation

Sara Merino-Aceituno·Carmela Moschella
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Abstract

In this work, we investigate an individual-based model (IBM) for self-propelled agents interacting locally on a plane. Agents are characterized by their position, the angle determining their direction of motion, and their angular velocity. The dynamics combine features of the well-known Vicsek and Kuramoto models, which describe collective dynamics and synchronization, respectively. The evolution of the directions of motion follows a Vicsek model, where agents align their orientations with the mean orientation of their neighbors, subject to some noise. Similarly, the angular velocities relax towards the average angular velocity of the neighboring agents, also subject to noise. From the IBM we derive the corresponding kinetic equation in the limit of a large number of agents and formally obtain the macroscopic equations through a macroscopic (hydrodynamic) limit. Numerical simulations of the IBM reveal a variety of patterns, including rotating clusters, traveling orientation waves, and globally synchronized rotational motion. A qualitative comparison with simulations of the macroscopic system show the ability of the macroscopic model to reproduce some emergent behavior of the IBM.

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Sara Merino-Aceituno, Carmela Moschella. 2025-12-18. The Vicsek-Kuramoto model in collective dynamics: macroscopic equations and pattern formation. https://arxiv.org/abs/2512.17035

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