Chip-Firing and Rotor-Routing on Directed Graphs
arXiv:0801.3306 · doi:10.1007/978-3-7643-8786-0_17
Abstract
We give a rigorous and self-contained survey of the abelian sandpile model and rotor-router model on finite directed graphs, highlighting the connections between them. We present several intriguing open problems.
34 pages, 11 figures. v2 has additional references, v3 corrects figure 9, v4 corrects several typos