Categorification of sheaf theory
Germán Stefanich
TL;DR
The paper develops a systematic framework to categorify presentable six-functor formalisms through higher-categorical correspondences, producing a sequence of categorified formalisms $n\\Sh$ that yield topological field theories valued in presentable higher categories. By enriching $n\\Corr(\\ccal)$ over $\\Corr(\\ccal)$ and constructing $n\\Sh^{\\sharp}$, it generalizes the factorization-homology viewpoint to general sheaf theories, addressing when $\\Sh(\\Maps(M,X))$ can be recovered as TFT data. Descent and affineness analyses provide practical tools to verify when these categorified theories behave like classical sheaf theories, with concrete results for $\\QCoh$, $\\IndCoh$, and Betti theories, and applications to structures such as Rozansky–Witten theory and geometric Langlands. The framework thus unifies six-functor formalisms, TFTs, and categorified sheaf theories, enabling new perspectives on microlocal and global aspects of sheaves of higher categories. Overall, it offers a formal pathway to extend factorization-homology computations to broad categorical settings and extract TFT-based invariants from generalized sheaf theories.
Abstract
We discuss a systematic procedure for categorifying presentable six-functor formalisms. Our main result produces, given the input of a representation of the $\infty$-category of correspondences of an $\infty$-category with finite limits $\mathcal{C}$, a compatible sequence of representations of the $(\infty,n)$-category of correspondences of $\mathcal{C}$ for every $n \geq 1$. As an application, we explain a general recipe for constructing topological field theories.
