Conjecture on quantum D-modules for primitive extremal transitions of Calabi–Yau threefolds

A primitive extremal transition is a transition between Calabi–Yau $3$-folds satisfying the hypotheses specified in the paper. The quantum D-module conjecture. The statement of Theorem A holds for any primitive extremal transition between two Calabi–Yau $3$-folds. This predicts that the relationship between the quantum D-modules established in Theorem A extends from the paper's setting to all primitive extremal transitions between Calabi–Yau threefolds. The conjecture is motivated by the fact that quantum D-modules remain well defined even when the corresponding $I$-functions cannot generally be written down.