Helly-type problems
Imre Bárány, Gil Kalai · Bulletin of the American Mathematical Society · 2021
In this paper we present a variety of problems in the interface between combinatorics and geometry around the theorems of Helly, Radon, Carathéodory, and Tverberg. Through these problems we describe the fascinating area of Helly-type theorems and explain some of their main themes and goals.