Relating categorical dimensions in topology and symplectic geometry

TL;DR

This paper explores the relationships between various notions of dimension in categories from topology and symplectic geometry, establishing bounds and connecting them to geometric invariants.

Contribution

It introduces bounds on categorical dimensions and relates them to geometric quantities like Morse critical points and Hamiltonian action values.

Findings

Bound on Rouquier dimension of wrapped Fukaya categories

Relation between categorical dimensions and geometric invariants

Introduction of Lusternik-Schnirelmann category for dg-categories

Abstract

We study several notions of dimension for (pre-)triangulated categories naturally arising from topology and symplectic geometry. We prove new bounds on these dimensions and raise several questions for further investigation. For instance, we relate the Rouquier dimension of the wrapped Fukaya category of either the cotangent bundle of a smooth manifold $M$ or more generally a Weinstein domain $X$ to quantities of geometric interest. These quantities include the minimum number of critical values of a Morse function on $M$, the Lusternik-Schnirelmann category of $M$, the number of distinct action values of a Hamiltonian diffeomorphism of $X$, and the smallest $n$ such that $X$ admits a Weinstein embedding into $\mathbb{R}^{2n+1}$. Along the way, we introduce a notion of the Lusternik-Schnirelmann category for dg-categories and construct exact Lagrangian cobordisms for restriction to a Liouville subdomain.