Title: Initial degenerations of Grassmannians
Speaker: Daniel Corey (Yale University)
Abstract: Let $Gr_0(d,n)$ denote the open subvariety of the Grassmannian $Gr(d,n)$ consisting of $d-1$ dimensional subspaces of $P^{n-1}$ meeting the toric boundary transversely. We prove that $Gr_0(d,n)$ is schoen in the sense that all of its initial degenerations are smooth. The main technique we will use is to express the initial degenerations of $Gr_0(3,7)$ as a inverse limit of thin Schubert cells. We use this to show that the Chow quotient of $Gr(d,n)$ by the maximal torus $H$ in $GL(n)$ is the log canonical compactification of the moduli space of 7 lines in $P^2$ in linear general position.
Seminar URL: https://people.math.osu.edu/anderson.2804/gcis/