Flock stability in the vicsek model

Abstract

The Standard Vicsek Model and a popular variant—using topological neighbour interactions—are widely used models for studying flocking phenomena in the natural world. It is capable of demonstrating the ordered and disordered states of real world flocks by tuning a temperature variable η, where high η corresponds to the disordered state. Here we show that the ordered state attained at low η is not stable over indefinite time periods raising implications for simulations and settling times. Additionally, we show that the loss of coherency in the metric case is reversible, while it is permanent in topological case.