Phase Diagram of the Two-Dimensional Vicsek Model

Yu Duan; Hugues Chaté; Benoît Mahault; Xia-qing Shi

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arXiv · 2610.26569

Phase Diagram of the Two-Dimensional Vicsek Model

Yu Duan·Hugues Chaté·Benoît Mahault·Xia-qing Shi

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Abstract

Motivated by gaps in our current knowledge of the Vicsek model, we present a major update of its phase diagram in two space dimensions, summarizing comprehensive numerical simulations at length- and timescales never explored before. Our main conclusions are that multiple phase separation scenarios are at play, not just the simple microphase separation put forward in [Phys. Rev. Lett. 114, 068101 (2015)], and that the coexistence phase is subdivided in two. We also map out the region of metastability of the homogeneous Toner-Tu liquid phase.

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Yu Duan, Hugues Chaté, Benoît Mahault, Xia-qing Shi. 2026-10-19. Phase Diagram of the Two-Dimensional Vicsek Model. https://arxiv.org/abs/2610.26569

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