2020/09/09 by István Tomon, Tomon, István, Dmitriy Zakharov +1 · 4 citations
Mathematics · Computer Science · #Advanced Combinatorial Mathematics #Advanced Graph Theory Research #Complexity and Algorithms in Graphs
paper · pdf · doi:10.48550/arxiv.2009.04380
In this short note, we prove the following analog of the Kővári-Sós-Turán theorem for intersection graphs of boxes. If G is the intersection graph of n axis-parallel boxes in ℝd such that G contains no copy of Kt,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 K2,2-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.