An isoperimetric constant for signed graphs

Antoine Gournay

doi:10.1016/j.exmath.2015.10.002

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arXiv · 1410.5995

An isoperimetric constant for signed graphs

Antoine Gournay

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Abstract

A sign is introduced in the usual Laplacian on graphs and the corresponding analogue of the isoperimetric constant for this Laplacian is presented, i.e. a geometric quantity which enables to bound from above and below the first eigenvalue. The introduction of the sign in the Laplacian is motivated by the study of $2$-lifts of graphs and of the combinatorial Laplacian in higher degree.

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Antoine Gournay. 2014-10-22. An isoperimetric constant for signed graphs. https://doi.org/10.1016/j.exmath.2015.10.002

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