Intersection patterns of planar sets
Combinatorics
2019-12-17 v2
Abstract
Let be a family of sets in the plane. For , denote by the number of subsets of of cardinality that satisfy . Let be an integer. We prove that if each -wise and -wise intersection of sets from is empty, or a single point, or both open and path-connected, then implies for some positive constant depending only on . Similarly, let be integers. We prove that if each -wise or -wise intersection of sets from has at most path-connected components, which all are open, then implies for some positive constant depending only on and . These results also extend to two-dimensional compact surfaces.
Cite
@article{arxiv.1907.00885,
title = {Intersection patterns of planar sets},
author = {Gil Kalai and Zuzana Patáková},
journal= {arXiv preprint arXiv:1907.00885},
year = {2019}
}