Directed percolation transition to active turbulence driven by non-reciprocal forces

Abstract

We numerically study the collective dynamics of dense particle assemblies driven by non-reciprocal pairwise forces of amplitude $\hat{I}º$. At a critical value $\hat{I}{º}_{\mathrm{c}}$, the system undergoes a dynamical phase transition from an absorbing state ($\hat{I}º<\hat{I}{º}_{\mathrm{c}}$) to a chaotic steady state ($\hat{I}º>\hat{I}{º}_{\mathrm{c}}$). The chaotic phase is marked by nontrivial spatiotemporal velocity correlations and mixing, reminiscent of active turbulence in self-propelled systems. The sharp onset of chaos shows critical scaling consistent with the universality class of directed percolation. We argue that this transition is generic to a broad class of locally-driven, dense disordered materials.

7 pages, 4 figures