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arXiv · 1404.4807

Tailoring the interactions between self-propelled bodies

Jean-Baptiste Caussin·Denis Bartolo
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Abstract

We classify the interactions between self-propelled particles moving at a constant speed from symmetry considerations. We establish a systematic expansion for the two-body forces in the spirit of a multipolar expansion. This formulation makes it possible to rationalize most of the models introduced so far within a common framework. We distinguish between three classes of physical interactions: (i) potential forces, (ii) inelastic collisions and (iii) non-reciprocal interactions involving polar or nematic alignment with an induced field. This framework provides simple design rules for the modeling and the fabrication of self-propelled bodies interacting via physical interactions. A class of possible interactions that should yield new phases of active matter is highlighted.

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Jean-Baptiste Caussin, Denis Bartolo. 2014-04-23. Tailoring the interactions between self-propelled bodies. https://arxiv.org/abs/1404.4807

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