Time: 15h15, Friday, 17/12/20211

Join Zoom Meeting
https://us02web.zoom.us/j/89603210669?pwd=dDJyYnJHd3A5WlR1cFFkRUlYa3loUT09

Meeting ID: 896 0321 0669

Passcode: 340252

Abstract: For a large class of GIT quotients, the moduli of epsilon-stable quasimaps is a proper Delinge-Mumford stack with a perfect obstruction theory. Thus K-theoretic epsilon-stable quasimap invariants are defined. As epsilon tends to infinity, it recovers the K-theoretic invariants; and as epsilon decreases, fewer and fewer rational tails are allowed in the domain curves. There is a wall and chamber structure on the space of stability conditions. In this talk, we will decribe a master space construction involoving the moduli spaces on the two sides of a wall, leading to the proof of a wall-crossing formula. A key ingredient is keeping track of the S_n-equivariant structure on the K-theoretic invariants.