Oct 21 2008 - 4:30pm
Oct 21 2008 - 5:30pm
Matthew Simpson
University of Michigan
Cockins 240 (old MBI lecture room)
There has been a long standing unproven conjecture by Fulton
regarding the structure of the cone of curves of the moduli space of stable
pointed genus zero curves. This
conjecture implies a similar conjecture for Hassett's weighted moduli spaces. In this talk I will review what is known and then discuss a
proof of this conjecture in the special case of small weights. The main technique involves
constructing contractions of the moduli space to variations of a certain GIT
quotient, using the universal properties of the moduli spaces. Fulton's conjecture gives us an upper
bound for the cone of curves. By
creating enough contractions we get a lower bound, which will turn out to agree
with the upper bound.