Singular Legendrian unknot links and relative Ginzburg algebras
Johan Asplund
TL;DR
This work builds a bridge between quiver data with frozen subquivers and symplectic invariants of stopped Weinstein manifolds by constructing a subcritical piece $Z_0(Q)$ and a singular Legendrian attaching link $\boldsymbol\Lambda(Q,F)$, then proving a quasi-isomorphism $CE^*(\boldsymbol\Lambda(Q,F);Z_0(Q))\simeq \mathscr G^*_n(Q,F)$ to the $n$-dimensional relative Ginzburg algebra. It shows that a canonical subalgebra corresponds to $\mathscr G^*_{n-1}(F)$ and that a strong relative smooth Calabi–Yau structure exists for the inclusion and the associated Ginzburg map, enabling derived equivalences between Perf of the CE-algebra and the partially wrapped Fukaya category via the Orlov functor. The proof combines a 1D simplicial decomposition, local Chekanov–Eliashberg calculations for simple Legendrian pieces, and a gluing/colimit framework to realize the global algebra as a relative Ginzburg algebra; explicit chain maps and homotopies establish the quasi-isomorphism and Calabi–Yau structures. This relative perspective extends known non-relative and weak-relative Calabi–Yau phenomena to stopped settings and sets the stage for pre-Calabi–Yau structures and nontrivial potentials in future work. Overall, the paper provides a concrete geometric-realization of relative Ginzburg algebras as Chekanov–Eliashberg algebras of singular Legendrians in stopped Weinstein boundaries, with strong Calabi–Yau control on both the algebra and the associated Orlov functor.
Abstract
We associate to a quiver and a subquiver $(Q,F)$ a stopped Weinstein manifold $X$ whose Legendrian attaching link is a singular Legendrian unknot link $\varLambda$. We prove that the relative Ginzburg algebra of $(Q,F)$ is quasi-isomorphic to the Chekanov--Eliashberg dg-algebra of $\varLambda$. It follows that the Chekanov--Eliashberg dg-algebra of $\varLambda$ relative to its boundary dg-subalgebra, and the Orlov functor associated to the partially wrapped Fukaya category of $X$ both admit a strong relative smooth Calabi--Yau structure.
