
We use wall-crossing for Bridgeland stability conditions to systematically study the birational
geometry of a moduli space M of Gieseker-stable sheaves on a K3 surface. In particular, we show:
- Any K-equivalent birational model of M appears as a moduli of Bridgeland stable objects, such that
the birational transformation is induced by wall-crossing.
- We complete Markman's proof the Kawamata-Morrison cone conjecture on the moveable cone of M.
- We establish the Hassett-Tschinkel/Huybrechts/Sawon conjecture on the existence of birational
Lagrangian fibrations whenever there exists a divisor of square zero with respect to the Beauville-Bogomolov
form.
This is based on joint work with Emanuele Macrì. The two main ingredients are the construction
of a canonical determinant line bundle on moduli spaces of Bridgeland-stable objects, and a detailed
analysis of walls for which every object becomes strictly semistable.
Links:
[1] http://www.mpim-bonn.mpg.de/taxonomy/term/39
[2] http://www.mpim-bonn.mpg.de/node/3444
[3] http://www.mpim-bonn.mpg.de/node/2804