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Rayleigh Matroids

Y. -B. Choe·D. G. Wagner
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Abstract

Motivated by a property of linear resistive electrical networks, we introduce the class of Rayleigh matroids. This is a subclass of the balanced matroids introduced by Feder and Mihail [FM] in 1992. We prove a variety of results relating Rayleigh matroids to other well-known classes -- in particular, we show that a binary matroid is Rayleigh if and only if it does not contain S_8 as a minor. This has the consequence that a binary matroid is balanced if and only if it is Rayleigh, and provides the first complete proof in print that S_8 is the only minor-minimal binary non-balanced matroid, as claimed in [FM]. We also give an example of a balanced matroid which is not Rayleigh.

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Y. -B. Choe, D. G. Wagner. 2003-09-05. Rayleigh Matroids. https://arxiv.org/abs/math/0307096

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