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arXiv · 2405.20891

On the largest independent sets in the Kneser graph on chambers of PG(4,q)

Philipp Heering
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Abstract

Let $Γ_4$ be the graph whose vertices are the chambers of the finite projective $4$-space PG(4,q), with two vertices being adjacent if the corresponding chambers are in general position. For $q\geq 749 $ we show that $α:=(q^2+q+1)(q^3+2q^2+q+1)(q+1)^2$ is the independence number of $Γ_4$ and the geometric structure of independent sets with $α$ vertices is described.

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Philipp Heering. 2024-05-31. On the largest independent sets in the Kneser graph on chambers of PG(4,q). https://arxiv.org/abs/2405.20891

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