Key points are not available for this paper at this time.
Donaldson–Thomas invariants D T α (τ) DT^ () are integers which ‘count’ τ -stable coherent sheaves with Chern character α on a Calabi–Yau 3-fold X X, where τ denotes Gieseker stability for some ample line bundle on X X. They are unchanged under deformations of X X. The conventional definition works only for classes α containing no strictly τ -semistable sheaves. Behrend showed that D T α (τ) DT^ () can be written as a weighted Euler characteristic χ (M s t α (τ), ν M <mml: mi mathvariant="
Joyce et al. (Mon,) studied this question.