A cellular-automata model of flow in ant-trails: non-monotonic variation of speed with density

Abstract

Generically, in models of driven interacting particles, the average speed of the particles decreases monotonically with increasing density. We propose a counterexample, motivated by the motion of ants in a trail, where the average speed of the particles varies non-monotonically with their density because of the coupling of their dynamics with another dynamical variable. These results, in principle, can be tested experimentally.