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arXiv · 2605.01421

Effective attraction by repulsion

Rosalba Garcia-Millan·Luca Cocconi·Ziluo Zhang·Marius Bothe·Letian Chen·Zigan Zhen·Gunnar Pruessner
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Abstract

Repulsive self-propelled particles tend to cluster, leading to Motility-Induced Phase Separation (MIPS). By analogy with equilibrium phase separation, the onset of MIPS has been associated with a transition to effective attraction between particles. Using an exact microscopic theory, we quantify the emergence of effective attraction in a minimal model: two soft run-and-tumble particles in a periodic domain. We show that, as repulsion increases, the leading-order behaviour is that of effective repulsion, while effective attraction emerges as a higher-order contribution to the renormalisation of the pair potential.

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BibTeXRIS

Rosalba Garcia-Millan, Luca Cocconi, Ziluo Zhang, Marius Bothe, Letian Chen, Zigan Zhen, Gunnar Pruessner. 2026-05-02. Effective attraction by repulsion. https://arxiv.org/abs/2605.01421

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