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arXiv · 1307.5703

Fourier analysis on finite groups and the Lovász theta-number of Cayley graphs

Evan DeCorte·David de Laat·Frank Vallentin
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Abstract

We apply Fourier analysis on finite groups to obtain simplified formulations for the Lovász theta-number of a Cayley graph. We put these formulations to use by checking a few cases of a conjecture of Ellis, Friedgut, and Pilpel made in a recent article proving a version of the Erdős-Ko-Rado theorem for $k$-intersecting families of permutations. We also introduce a $q$-analog of the notion of $k$-intersecting families of permutations, and we verify a few cases of the corresponding Erdős-Ko-Rado assertion by computer.

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Evan DeCorte, David de Laat, Frank Vallentin. 2013-07-22. Fourier analysis on finite groups and the Lovász theta-number of Cayley graphs. https://doi.org/10.1080/10586458.2014.882170

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