2 problems

Let $M$ be a realizable oriented matroid of rank $n$, and let $\mathcal G(r,M)$ denote the combinatorial Grassmannian formed from the rank-$r$ strong images of $M$. Let…

Grassmannian conjecture. For generic $N$, ${\cal C}_N$ is isomorphic to a combinatorial Grassmannian of type $G_2(N+1)$.