(HoRSe seminar) Localized virtual cycles, and applications to GW and DT invariants I

(HoRSe seminar) Localized virtual cycles, and applications to GW and DT invariants I

Tue, 25/01/2011
14:00 		Jun Li (Stanford) Algebraic and Symplectic Geometry Seminar Add to calendar SR1
(HoRSe seminar) Localized virtual cycles, and applications to GW and DT invariants I
We first present the localized virtual cycles by cosections of obstruction sheaves constructed by Kiem and Li. This construction has two kinds of applications: one is define invariants for non-proper moduli spaces; the other is to reduce the obstruction classes. We will present two recent applications of this construction: one is the Gromov-Witten invariants of stable maps with fields (joint work with Chang); the other is studying Donaldson-Thomas invariants of Calabi-Yau threefolds (joint work with Kiem).