| Speaker: | Felix Thimm (Univ. of British Columbia) |
|---|---|
| Title: | Factorization of K-theoretic orbifold DT invariants |
| Date (JST): | Tue, Sep 30, 2025, 13:30 - 15:00 |
| Place: | Seminar Room A |
| Abstract: | Degree 0 Donaldson-Thomas invariants of orbifolds count 0-dimensional substacks and are related to counts of colored plane (or solid) partitions, where the boxes are colored in a way determined by the orbifold structure. This allows the computation of closed formulas for some orbifolds. The refinement of those formulas to K-theoretic DT theory involves an extension of Okounkov's factorization technique to the orbifold setting, which we will explain. We then show that an appropriate twist of the virtual structure sheaf is factorizable in DT theory of orbifolds of dimension 3 and 4, and how this twist naturally arises if we want factorizable invariants. |
