We construct a class of perturbations of the Cauchy-Riemann equation for maps from curves
to a Calabi-Yau threefold, allowing Maslov zero Lagrangian boundary conditions. Our …

Kim, Kresch and Oh defined unramified Gromov-Witten invariants. For a threefold,
Pandharipande conjectured that they are equal to Gopakumar-Vafa invariants (BPS …

Given F a coherent sheaf on a Noetherian integral algebraic stack P, we give two
constructions of stacks P'equipped with birational morphisms p from P'to P such that p* F is …