VOA[M4]
Boris Feigin, Sergei Gukov
TL;DR
This work proposes a dictionary between smooth 4-manifolds and vertex operator algebras, where gluing of manifolds corresponds to VOA extensions and BRST reductions. By identifying VOA$[M_4]$ as the left-moving chiral algebra of the 2d theory $T[M_4]$ arising from compactification of the 6d $(0,2)$ theory, the authors connect 4-manifold invariants like Vafa–Witten partition functions to VOA characters and lattice VOAs, while modular tensor categories $MTC[M_3]$ encode boundary data for gluing along 3-manifolds. They develop gluing via both extensions (e.g., toric patches) and BRST reduction (e.g., product ruled surfaces, trisections), and they illustrate this with explicit constructions for blow-ups, orientation reversals, Kirby moves, and trialities, as well as with trisection-based building blocks. The framework yields new pathways to 4-manifold invariants and dualities, enriched by the interplay of 2d/3d/6d theories, and motivates further study of associated varieties, wall-crossing phenomena, and higher-rank generalizations. Overall, the paper advances a cohesive algebraic-topological program to extract and compare invariants across manifold decompositions via VOA and MTC data, with concrete examples and several promising conjectures for broader applicability.
Abstract
We take a peek at a general program that associates vertex (or, chiral) algebras to smooth 4-manifolds in such a way that operations on algebras mirror gluing operations on 4-manifolds and, furthermore, equivalent constructions of 4-manifolds give rise to equivalences (dualities) of the corresponding algebras.
