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

2014/09/11 by Ferdinand Ihringer, Ihringer, Ferdinand
Computer Science · Mathematics · #05B25 #51E20 #Advanced Topics in Algebra #Coding theory and cryptography #Combinatorics (math.CO) #FOS: Mathematics #Finite Group Theory Research

paper · pdf · doi:10.48550/arxiv.1409.3606

openalex publication_date 2014/09/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

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 ∈ Y and z ∈ Z intersect in at least a point. We provide upper bounds on |Y| ⋅ |Z| and classify the cross-intersecting Erdős-Ko-Rado sets of maximum size with respect to |Y| ⋅ |Z| for all polar spaces except Hermitian polar spaces in odd projective dimension.

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