Emergent Defect Dynamics in Two-Dimensional Cellular Automata
Martin Delacourt and Marcus Pivato
A cellular automaton (CA) exhibits ‘emergent defect dynamics’ (EDD) if generic initial conditions rapidly coalesce into large, homogeneous ‘domains’ (exhibiting some spatial pattern) separated by moving ‘defects’. There are many known examples of EDD in one-dimensional CA, but not in higher dimensions. We describe the results of an automated search for two-dimensional CA exhibiting EDD. We found a plethora of examples of EDD, but we also found that the proportion of CA with EDD declines rapidly with increasing neighbourhood size.