Orbits of rotor-router operation and stationary distribution of random walks on directed graphs

Trung Van Pham
2015 Advances in Applied Mathematics  
The rotor-router model is a popular deterministic analogue of random walk. In this paper we prove that all orbits of the rotor-router operation have the same size on a strongly connected directed graph (digraph) and give a formula for the size. By using this formula we address the following open question about orbits of the rotor-router operation: Is there an infinite family of non-Eulerian strongly connected digraphs such that the rotor-router operation on each digraph has a single orbit? It
more » ... rns out that on a strongly connected digraph the stationary distribution of the simple random walk coincides with the frequency of vertices in a rotor walk. In this common aspect a rotor walk simulates a random walk. This gives one similarity between two models on (finite) digraphs.
doi:10.1016/j.aam.2015.06.006 fatcat:bcz5dfs745eyflt67ebegz7key