English

Apollonian structure in the Abelian sandpile

Analysis of PDEs 2014-05-23 v2 Statistical Mechanics Combinatorics Number Theory

Abstract

The Abelian sandpile process evolves configurations of chips on the integer lattice by toppling any vertex with at least 4 chips, distributing one of its chips to each of its 4 neighbors. When begun from a large stack of chips, the terminal state of the sandpile has a curious fractal structure which has remained unexplained. Using a characterization of the quadratic growths attainable by integer-superharmonic functions, we prove that the sandpile PDE recently shown to characterize the scaling limit of the sandpile admits certain fractal solutions, giving a precise mathematical perspective on the fractal nature of the sandpile.

Cite

@article{arxiv.1208.4839,
  title  = {Apollonian structure in the Abelian sandpile},
  author = {Lionel Levine and Wesley Pegden and Charles K. Smart},
  journal= {arXiv preprint arXiv:1208.4839},
  year   = {2014}
}

Comments

27 Pages, 7 Figures

R2 v1 2026-06-21T21:54:37.494Z