Pattern formation in growing sandpiles

EPL (Europhysics Letters) (Impact Factor: 2.26). 08/2008; DOI: 10.1209/0295-5075/85/48002
Source: arXiv

ABSTRACT Adding grains at a single site on a flat substrate in the Abelian sandpile models produce beautiful complex patterns. We study in detail the pattern produced by adding grains on a two-dimensional square lattice with directed edges (each site has two arrows directed inward and two outward), starting with a periodic background with half the sites occupied. The size of the pattern formed scales with the number of grains added $N$ as $\sqrt{N}$. We give exact characterization of the asymptotic pattern, in terms of the position and shape of different features of the pattern. Comment: 5 pages, 4 figures, submitted to Phys. Rev. Lett

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