Ana-Maria Castravet
Hypergraphs and moduli of curves
We give many examples of extremal divisors, rigid curves, and
birational
morphisms with unexpected properties for the Grothendieck--Knudsen
moduli
space $\bar M_{0,n}$ of stable rational curves. The basic tool is an
isomorphism between $M_{0,n}$ and the Brill--Noether locus of a very
special reducible curve corresponding to a hypergraph. This is joint
work
with Jenia Tevelev.