Strict Erdős-Ko-Rado theorems for simplicial complexes

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Bulavka, Denys, Woodroofe, Russ
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911031166500864
author Bulavka, Denys
Woodroofe, Russ
author_facet Bulavka, Denys
Woodroofe, Russ
contents We show that if a simplicial complex is a near-cone of sufficiently high depth, then the only maximum families of small pairwise intersecting faces are those with a common intersection. Thus, near-cones of sufficiently high depth satisfy the strict Erdős-Ko-Rado property conjectured by Holroyd and Talbot and by Borg. One consequence is a strict Erdős-Ko-Rado theorem for independence complexes of chordal graphs with an isolated vertex. Under stronger shiftedness conditions, we prove a sharper stability theorem of Hilton-Milner type, as well as two cross-intersecting theorems.
format Preprint
id arxiv_https___arxiv_org_abs_2503_15608
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Strict Erdős-Ko-Rado theorems for simplicial complexes
Bulavka, Denys
Woodroofe, Russ
Combinatorics
05D05, 05E45
We show that if a simplicial complex is a near-cone of sufficiently high depth, then the only maximum families of small pairwise intersecting faces are those with a common intersection. Thus, near-cones of sufficiently high depth satisfy the strict Erdős-Ko-Rado property conjectured by Holroyd and Talbot and by Borg. One consequence is a strict Erdős-Ko-Rado theorem for independence complexes of chordal graphs with an isolated vertex. Under stronger shiftedness conditions, we prove a sharper stability theorem of Hilton-Milner type, as well as two cross-intersecting theorems.
title Strict Erdős-Ko-Rado theorems for simplicial complexes
topic Combinatorics
05D05, 05E45
url https://arxiv.org/abs/2503.15608