Emergent Active Clusters through Wave-Mediated Interactions

Abstract

Collective behaviour in active matter usually emerges from interactions between individually stable units. Here we demonstrate a different route to collective organization using droplets on a vibrated fluid bath. Large droplets that are unstable in isolation become persistent active clusters through a shared Faraday wavefield. The same wave-mediated interactions that stabilize these clusters also govern their collective dynamics, producing stationary, rotating, and translating states as droplet size is varied. Our results show how field-mediated interactions can transform individually unstable particles into coherent active entities with emergent structure and function.

9 pages, 6 figures