On the Morita invariance of Categorical Enumerative Invariants
Lino Amorim, Junwu Tu
TL;DR
This work develops CEI for Calabi–Yau $A_ infty$-categories with a nc-Hodge filtration splitting and proves their Morita invariance. It introduces unital cyclic CY models via a unital Darboux-type result, and builds a robust TCFT/DGLA framework to define genus-$g$ CEI $F^{\mathcal{C},s}_{g,n}$ that are independent of cyclic models and invariant under Morita equivalence. The results yield new invariants for smooth, proper CY3s and connect to classical enumerative theories (GW and BCOV), with concrete computations in matrix factorization settings and Frobenius algebras, and conjectural links to open–closed maps in the A-model. Overall, the paper provides a principled Morita-invariant mechanism to extract enumerative invariants from categories, with broad implications for homological mirror symmetry and topological string theory.
Abstract
Categorical Enumerative Invariants (CEI) are invariants associated with a unital, cyclic, smooth $A_\infty$-category and a splitting of its non-commutative Hodge filtration. In this paper, we extend the definition of CEI to Calabi-Yau $A_\infty$-categories with a splitting. Moreover, we formulate and prove the Morita invariance of CEI. As part of our proof, we develop tools to construct unital and cyclic models for Calabi-Yau categories. In particular, we prove a unital version of Kontsevich-Soibelman's Darboux theorem. As an application, we compute CEI in some new examples. Also, when applied to derived categories of coherent sheaves, our results yield new invariants of smooth, proper Calabi-Yau 3-folds.
