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arXiv · 2010.04521

Effective resistance is more than distance: Laplacians, Simplices and the Schur complement

Karel Devriendt
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Abstract

This article discusses a geometric perspective on the well-known fact in graph theory that the effective resistance is a metric on the nodes of a graph. The classical proofs of this fact make use of ideas from electrical circuits or random walks; here we describe an alternative approach which combines geometric (using simplices) and algebraic (using the Schur complement) ideas. These perspectives are unified in a matrix identity of Miroslav Fiedler, which beautifully summarizes a number of related ideas at the intersection of graphs, Laplacian matrices and simplices, with the metric property of the effective resistance as a prominent consequence.

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BibTeXRIS

Karel Devriendt. 2020-10-09. Effective resistance is more than distance: Laplacians, Simplices and the Schur complement. https://doi.org/10.1016/j.laa.2022.01.002

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