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Laplacians and the Cheeger Inequality for Directed Graphs
Fan Chung
University of California, San Diego, La Jolla, CA 92093-0112, USA
Annals of Combinatorics 9 (1) p.1-19 March, 2005
AMS Subject Classification: 05C20, 05C50, 15A42, 60J05
We consider Laplacians for directed graphs and examine their eigenvalues. We introduce a notion of a circulation in a directed graph and its connection with the Rayleigh quotient. We then define a Cheeger constant and establish the Cheeger inequality for directed graphs. These relations can be used to deal with various problems that often arise in the study of non-reversible Markov chains including bounding the rate of convergence and deriving comparison theorems.
Keywords: eigenvalues, Laplacian, circulation, the Cheeger inequality, random walks, Markov chains, comparison theorems


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