A new mechanism of aggregation in a lattice-gas cellular automaton model

A cellular automaton with moving and resting “particles” is introduced as a model of swarming and aggregation. No external (indirect) sources of information (e.g., chemoattractants) are needed. Instead, “particles” are capable of (directly) evaluating orientations as well as the rest particle density in their local vicinity. Simulations exhibit transitions from random movement to collective motion and, furthermore, to aggregation. Mean-field analysis of the “aggregation instability” provides an explanation of spatial pattern formation.