Anisotropy and Cluster Growth by Diffusion-Limited Aggregation

Abstract

We describe a simple theory of diffusion-limited-aggregation cluster growth which relates the large-scale shape of the cluster to its fractal dimension. We present results of computer simulation for DLA clusters grown with anisotropic sticking rules which provide strong confirmation of our model in two dimensions. New universal exponents are predicted and found. We are also able to obtain good estimates for the fractal dimension of ordinary DLA.