Higher categories of push-pull spans, II: Matrix factorizations
Lorenzo Riva
TL;DR
The paper develops a bridge between matrix factorizations and the derived symplectic 2-category CRW by constructing a symmetric monoidal 2-functor $rak e$ from the 2-category $ extbf{MF}$ of matrix factorizations to the homotopy 2-category $ extbf{h}_2 extbf{CRW}$. It shows that the image lands in affine cotangent stacks $ ext{T}^ullet b K^n$ and proves that all objects in the target are 2-dualizable, enabling explicit computations of 2d topological field theories associated to affine symplectic derived stacks, including a canonical Serre-trivialization. The work reveals that while a full 3-dualizability lift is obstructed for affine cases like $ ext{T}^ullet b K^n$, the constructed TFTs recover Hochschild-type invariants such as $ ext{Spec HC}(A)$ on $S^1$ and intricate genus-$g$ expressions, thus connecting matrix-factorization data to categorical field theory in a precise algebraic framework. An open algebraic question about reconstructing matrix factorizations from endomorphism dg-modules over $A_V$ is posed for future study, signaling deeper insights into the derived Morita aspects of the correspondence.
Abstract
This is the second part of a project aimed at formalizing Rozansky-Witten models in the functorial field theory framework. In the first part we constructed a symmetric monoidal $(\infty, 3)$-category $\mathscr{CRW}$ of commutative Rozansky-Witten models with the goal of approximating the $3$-category of Kapustin and Rozansky. In this paper we extend work of Brunner, Carqueville, Fragkos, and Roggenkamp on the affine Rozansky-Witten models: we exhibit a functor connecting their $2$-category of matrix factorizations with the homotopy $2$-category of $\mathscr{CRW}$, and calculate the associated TFTs.
