Augmentations are Sheaves
File(s)augmain.pdf (969.19 KB)
Accepted version
Author(s)
Ng, Lenhard
Rutherford, Dan
Shende, Vivek
Sivek, Steven
Zaslow, Eric
Type
Journal Article
Abstract
We show that the set of augmentations of the Chekanov-Eliashberg algebra of a
Legendrian link underlies the structure of a unital A-infinity category. This
differs from the non-unital category constructed in [BC], but is related to it
in the same way that cohomology is related to compactly supported cohomology.
The existence of such a category was predicted by [STZ], who moreover
conjectured its equivalence to a category of sheaves on the front plane with
singular support meeting infinity in the knot. After showing that the
augmentation category forms a sheaf over the x-line, we are able to prove this
conjecture by calculating both categories on thin slices of the front plane. In
particular, we conclude that every augmentation comes from geometry.
Legendrian link underlies the structure of a unital A-infinity category. This
differs from the non-unital category constructed in [BC], but is related to it
in the same way that cohomology is related to compactly supported cohomology.
The existence of such a category was predicted by [STZ], who moreover
conjectured its equivalence to a category of sheaves on the front plane with
singular support meeting infinity in the knot. After showing that the
augmentation category forms a sheaf over the x-line, we are able to prove this
conjecture by calculating both categories on thin slices of the front plane. In
particular, we conclude that every augmentation comes from geometry.
Date Issued
2020-12-29
Date Acceptance
2019-12-07
Citation
Geometry and Topology, 2020, 24 (5), pp.2149-2286
ISSN
1364-0380
Publisher
Mathematical Sciences Publishers
Start Page
2149
End Page
2286
Journal / Book Title
Geometry and Topology
Volume
24
Issue
5
Copyright Statement
© Copyright 2020 Mathematical Sciences Publishers. All rights reserved.
Identifier
http://arxiv.org/abs/1502.04939v2
Subjects
math.SG
math.SG
math.GT
Notes
102 pages; v2: added Legendrian mirror example in section 4.4.4, corrected typos and other minor changes
Publication Status
Published
Date Publish Online
2020-12-29