Stratifications of GIT quotients

Thursday, March 19, 2020 - 2:00pm
Math 312
Chi-Yu Cheng
Univ. of Washington

 Mumford's GIT quotient is one way to construct moduli spaces that parametrizes classes of algebro-geometric objects. It turns out there is an interesting structure on the set of unstable points discarded in the GIT quotient construction. In this talk I would aim to describe:

1. the stratification of the unstable points and its variation caused by different choice of linearizations;

2. wall and chamber decomposition analogous to Variation of Geometric Invariant Theory Quotient;

3.examples and results in the case of projective toric varieties.