The categorical DT/PT correspondence and quasi-BPS categories for local surfaces

Abstract We construct semiorthogonal decompositions of Donaldson–Thomas (DT) categories for reduced curve classes on local surfaces into products of quasi-BPS categories and Pandharipande–Thomas (PT) categories, giving a categorical analogue of the numerical DT/PT correspondence for Calabi–Yau 3-folds. The main ingredient is a categorical wall-crossing formula for DT/PT quivers (which appear as Ext quivers in the DT/PT wall-crossing) proved in our previous paper. We also study quasi-BPS categories of points on local surfaces and propose conjectural computations of their K-theory analogous to formulas already known for the three-dimensional affine space.