Categorical matrix factorizations and monomorphism categories
Jonas Frank, Mathias Schulze
TL;DR
This work develops a purely categorical generalization of Eisenbud–Yoshino’s matrix factorization correspondence by replacing hypersurface rings with a general exact category $\mathcal{A}$ equipped with a twisted homothety $(\tau,\omega)$. It defines hypersurface categories $\mathcal{A}/\omega$ and studies factorizations over Frobenius subcategories, showing these form a Frobenius category and giving a triangle equivalence between their stable category and the stable category of chains of monomorphisms in $\mathcal{E}_{\omega}$. The core construction uses a generalized cokernel functor and a suite of adjunctions between factorization diagrams and monomorphism chains, and it interprets factorizations as comma/diagram categories to connect to derivations in $\mathcal{E}_{\omega}$. Under suitable Ext-vanishing conditions, the main result yields a triangle equivalence between $\ul{\mathrm{Fac}}^{\mathcal{E}}_{l+1}(\omega)$ and $\ul{\mathrm{Mor}}^{\mathrm{m}}_{l-1}(\mathcal{E}_{\omega})$, unifying previous module-based results and extending to multi-factor factorizations. This framework provides a powerful categorical lens for understanding matrix factorizations and their relations to representation theory via Frobenius and Morita-theoretic structures.
Abstract
This article generalizes the correspondence between matrix factorizations and maximal Cohen-Macaulay modules over hypersurface rings due to Eisenbud and Yoshino. We consider factorizations with several factors in a purely categorical context, extending results of Sun and Zhang for Gorenstein projective module factorizations. Our formulation relies on a notion of hypersurface category and replaces Gorenstein projectives by objects of general Frobenius exact subcategories. We show that factorizations over such categories form again a Frobenius category. Our main result is then a triangle equivalence between the stable category of factorizations and that of chains of monomorphisms.
