Birational Calabi-Yau 3-folds and BPS state counting
Abstract
Description
This paper contains some applications of Bridgeland-Douglas stability conditions on triangulated categories, and Joyce's work on counting invariants of semistable objects, to the study of birational geometry. We introduce the notion of motivic Gopakumar-Vafa invariants as counting invariants of D2-branes, and show that they are invariant under birational transformations between Calabi-Yau 3-folds. The result is similar to the fact that birational Calabi-Yau 3-folds have the same betti numbers or Hodge numbers.
Some explanations and proofs are added. To appear in Communications in Number Theory and Physics
Some explanations and proofs are added. To appear in Communications in Number Theory and Physics