The unavoidable arrangements of pseudocircles

Abstract

A fact closely related to the classical Erdos-Szekeres theorem is that cyclic arrangements are the only unavoidable simple arrangements of pseudolines: for each fixed m ≥ 1, every sufficiently large simple arrangement of pseudolines has a cyclic subarrangement of size m. In the same spirit, we show that there are three unavoidable arrangements of pseudocircles.