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arXiv · 1403.5875

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

Trung Van Pham
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Abstract

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 turns 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.

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Trung Van Pham. 2014-03-24. Orbits of rotor-router operation and stationary distribution of random walks on directed graphs. https://doi.org/10.1016/j.aam.2015.06.006

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