An Introduction to Quantum Sheaf Cohomology - Physics - Virginia ...

(cont’d)
Need to compute coboundary maps.
Recall def’n
0 −→ S i −→ Λ i Z ⊗ Sym 2d+2e+2−i W −→ S i−1 −→ 0
Can show the
Λ i Z
only have nonzero cohomology
in degrees 2d+2, 2e+2
Thus, the coboundary maps
δ : H i (S i ) −→ H i+1 (S i+1 )
are mostly isomorphisms; the rest have
computable kernels.
(cont’d)