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arXiv · 1409.3606

Cross-Intersecting Erdős-Ko-Rado Sets in Finite Classical Polar Spaces

Ferdinand Ihringer
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Abstract

A cross-intersecting Erdős-Ko-Rado set of generators of a finite classical polar space is a pair $(Y, Z)$ of sets of generators such that all $y \in Y$ and $z \in Z$ intersect in at least a point. We provide upper bounds on $|Y| \cdot |Z|$ and classify the cross-intersecting Erdős-Ko-Rado sets of maximum size with respect to $|Y| \cdot |Z|$ for all polar spaces except Hermitian polar spaces in odd projective dimension.

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Ferdinand Ihringer. 2014-09-11. Cross-Intersecting Erdős-Ko-Rado Sets in Finite Classical Polar Spaces. https://arxiv.org/abs/1409.3606

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