Flocking at the edge of chaos

TL;DR

This paper introduces a topology-based self-propelled particle model that exhibits spontaneous fluctuations and scale-free correlations, suggesting that flocks may naturally organize at criticality through self-organized criticality.

Contribution

It presents a novel topology-driven model demonstrating spontaneous fluctuations and criticality in flocking behavior, advancing understanding of collective motion.

Findings

Force fluctuations occur spontaneously without noise.

Scale-free correlations emerge in the model.

Evidence suggests self-organized criticality as underlying mechanism.

Abstract

Recent investigations have provided important insights into the complex structure and dynamics of collectively moving flocks of living organisms. Two intriguing observations are, scale-free correlations in the velocity fluctuations, in the presence of a high degree of order, and topological distance mediated interactions. Understanding these features, especially, the origin of fluctuations, appears to be challenging in the current scheme of models. It has been argued that flocks are poised at criticality. We present a self-propelled particle model where neighbourhoods and forces are defined through topology based rules. The force fluctuations occur spontaneously, and gives rise to scale-free correlations in the absence of noise and in the presence of alignment of velocities. We characterize the behaviour of the model through power spectral densities and the Lyapunov spectrum. Our investigations suggest self-organized criticality as a probable route to the existence of criticality in flocks.