On Fukaya categories and prequantization bundles
Tatsuki Kuwagaki, Adrian Petr, Vivek Shende
TL;DR
This work develops a comprehensive bridge between Lagrangian Floer theory in nonexact, compact symplectic manifolds and exact data living on prequantization fillings. By organizing the algebraic and geometric information through pogs, orbit categories, and completion techniques, it expresses Fukaya categories of rational, nonexact Lagrangians in terms of Novikov-augmented data derived from exact fillings and Legendrian invariants. A central achievement is the Fukaya–sheaf correspondence, which relates Fukaya categories to microsheaves and to augmentation categories, and is compatible with wrapped/partially wrapped theories and with Legendrian isotopy of bounding cochains. The paper culminates with concrete computations, notably recovering the quantum cohomology of $\mathbb{C}P^1$ from purely sheaf-theoretic data, highlighting the potential of this framework to compute Floer-theoretic invariants via microlocal and algebraic methods.
Abstract
We show: the Floer homology over the Novikov ring of (nonexact!) rational Lagrangians in an (nonexact!) integral symplectic manifold can be computed in terms of exact Lagrangians in an exact filling of the prequantization bundle. As a consequence, we give a Fukaya-sheaf correspondence for rational (nonexact!) Lagrangians in Weinstein manifolds, as conjectured by Ike and the first-named author. We also show that bounding cochains for immersed rational Lagrangians transform naturally under Legendrian isotopy, as conjectured by Akaho and Joyce. As an illustration, we show that quantum cohomology of the complex projective line -- which requires the counting of one holomorphic sphere -- can be recovered from purely sheaf-theoretic calculations.
