{ "id": "2009.04380", "version": "v1", "published": "2020-09-09T15:58:37.000Z", "updated": "2020-09-09T15:58:37.000Z", "title": "Turán-type results for intersection graphs of boxes", "authors": [ "István Tomon", "Dmitriy Zakharov" ], "comment": "4 pages", "categories": [ "math.CO" ], "abstract": "In this short note, we prove the following analog of the K\\H{o}v\\'ari-S\\'os-Tur\\'an theorem for intersection graphs of boxes. If $G$ is the intersection graph of $n$ axis-parallel boxes in $\\mathbb{R}^{d}$ such that $G$ contains no copy of $K_{t,t}$, then $G$ has at most $ctn(\\log n)^{2d+3}$ edges, where $c=c(d)>0$ only depends on $d$. Our proof is based on exploring connections between boxicity, separation dimension and poset dimension. Using this approach, we also show that a construction of Basit et al. of $K_{2,2}$-free incidence graphs of points and rectangles in the plane can be used to disprove a conjecture of Alon et al. We show that there exist graphs of separation dimension 4 having superlinear number of edges.", "revisions": [ { "version": "v1", "updated": "2020-09-09T15:58:37.000Z" } ], "analyses": { "keywords": [ "intersection graph", "turán-type results", "separation dimension", "free incidence graphs", "superlinear number" ], "note": { "typesetting": "TeX", "pages": 4, "language": "en", "license": "arXiv", "status": "editable" } } }