Convex geometries representable with colors, by ellipses on the plane, and impossible by circles

Kira Adaricheva, Evan Daisy, Ayush Garg +5

A convex geometry is a closure system satisfying the anti-exchange property. This paper, following the work of K. Adaricheva and M. Bolat (2016) and the Polymath REU 2020 team, con…