Speaker: Daniel McGinnis

Title: A family of convex sets in the plane satisfying the (4,3)-property can be pierced by 9 points

Abstract: We prove that every finite family of convex sets in the plane satisfying the (4,3)-property can be pierced by 9 points. This improves the bound of 13 proved by Gyarfas, Kleitman, and Toth in 2001.