Aganagic's invariant is Khovanov homology
Elise LePage, Vivek Shende
TL;DR
The paper proves that Aganagic's Coulomb-branch (monodromy) construction of knot invariants and Webster's diagrammatic braid action are canonically intertwined for the case of the Dynkin diagram vertex, thereby giving a rigorous symplectic realization of Khovanov homology over the integers. By embedding Webster's weighty combinatorial category into the Fukaya-Seidel category of the multiplicative Coulomb branch and establishing a natural intertwining between the braid actions, the authors show Kh(\overline{\beta}) is recovered as a Hom-space in Fukaya-Seidel theory, with the Jones-graded and quantum gradings matched via the J, u, and \hbar gradings. The core steps involve (i) a detailed calculation of the braid action on simple KLRW objects and their cones, (ii) an explicit geometric realization of these objects as Lagrangians in Fukaya-Seidel categories with a cylindrical model for disk counts, and (iii) a precise comparison of caps and cups across the two formalisms, culminating in an intertwining theorem for braiding and cup/cap operations. The results provide a rigorous, integral verification of Aganagic's proposal and connect diagrammatic categorifications with symplectic constructions in a concrete, computable setting. This sharpens the link between combinatorial categorifications and symplectic/topological field theory perspectives on knot homology, with potential to extend to broader Lie types and superalgebras via the same monodromy framework.
Abstract
On the Coulomb branch of a quiver gauge theory, there is a family of functions parameterized by choices of points in the punctured plane. Aganagic has predicted that Khovanov homology can be recovered from the braid group action on Fukaya-Seidel categories arising from monodromy in said space of potentials. These categories have since been rigorously studied, and shown to contain a certain (combinatorially defined) category on which Webster had previously constructed a (combinatorially defined) braid group action from which the Khovanov homology can be recovered. Here we show, by a direct calculation, that the aforementioned containment intertwines said combinatorially defined braid group action with the braid group action arising naturally from monodromy. This provides a mathematical verification that Aganagic's proposal gives a symplectic construction of Khovanov homology -- with both gradings, and over the integers.
