Graphs and Matroids Seminar - Zach Walsh

Wednesday, June 26, 2019 3:30 pm - 3:30 pm EDT (GMT -04:00)

Title: Quadratically Dense Matroids

Speaker: Zach Walsh
Affiliation: University of Waterloo
Room: MC 5479


We discuss recent work proving that for any integer $t\ge 2$, any maximum-sized simple $\mathbb C$-representable matroid $M$ of large rank with no $U_{2,t+3}$-minor satisfies $|M|=t{r(M)\choose 2}+r(M)$. It was not our intention to prove this result, so we will first explain our original motivation. We assume only basic knowledge of matroid theory.

Joint work with Jim Geelen and Peter Nelson.