The sutured Floer polytope and taut depth one foliations

TL;DR

This paper extends the relationship between Floer homology and the Thurston norm from closed 3-manifolds to sutured manifolds, establishing a bijection between Floer polytope vertices and taut depth one foliations, with duality involving a new geometric norm.

Contribution

It introduces a bijection and duality between the sutured Floer polytope and taut depth one foliations for sutured manifolds, generalizing known results from closed 3-manifolds.

Findings

Establishes a bijection between vertices of the sutured Floer polytope and taut depth one foliations.

Shows the geometric sutured function is an asymmetric norm analogous to the Thurston norm.

Proves a sutured manifold admits a fibration or taut depth one foliation iff it admits a specific surface decomposition.

Abstract

For closed 3-manifolds, Heegaard Floer homology is related to the Thurston norm through results due to Ozsv\'ath and Szab\'o, Ni, and Hedden. For example, given a closed 3-manifold Y, there is a bijection between vertices of the HF^+(Y) polytope carrying the group Z and the faces of the Thurston norm unit ball that correspond to fibrations of Y over the unit circle. Moreover, the Thurston norm unit ball of Y is dual to the polytope of \underline{\hfhat}(Y). We prove a similar bijection and duality result for a class of 3-manifolds with boundary called sutured manifolds. A sutured manifold is essentially a cobordism between two surfaces R_+ and R_- that have nonempty boundary. We show that there is a bijection between vertices of the sutured Floer polytope carrying the group Z and equivalence classes of taut depth one foliations that form the foliation cones of Cantwell and Conlon. Moreover, we show that a function defined by Juh\'asz, which we call the geometric sutured function,is analogous to the Thurston norm in this context. In some cases, this function is an asymmetric norm and our duality result is that appropriate faces of this norm's unit ball subtend the foliation cones. An important step in our work is the following fact: a sutured manifold admits a fibration or a taut depth one foliation whose sole compact leaves are exactly the connected components of R_+ and R_-, if and only if, there is a surface decomposition of the sutured manifold resulting in a connected product manifold.