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arXiv · 2508.11793

Collective ballistic motion explains fast aggregation in adhesive active matter

Emanuel F. Teixeira·Pablo de Castro·Carine P. Beatrici·Heitor C. M. Fernandes·Leonardo G. Brunnet
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Abstract

Inspired by motile cells in tissue formation, we find that active systems of self-aligning adhesive particles undergo ballistic aggregation through a flocking transition. This kinetic regime emerges when the cluster persistence length grows faster with cluster mass than the intercluster distance does. We also identify and explain distinct non-collective kinetic regimes, including biologically relevant long-lived transients. Our analytical and numerical results offer a unified framework explaining the broad range of experimentally observed aggregation exponents in cellular systems and reveal physical principles potentially critical for timely tissue organization.

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Emanuel F. Teixeira, Pablo de Castro, Carine P. Beatrici, Heitor C. M. Fernandes, Leonardo G. Brunnet. 2025-08-15. Collective ballistic motion explains fast aggregation in adhesive active matter. https://arxiv.org/abs/2508.11793

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