The Bar-Natan homology and unknotting number
Geometric Topology
2019-09-18 v1
Abstract
We show that the order of torsion homology classes in Bar-Natan deformation of Khovanov homology is a lower bound for the unknotting number. We give examples of knots that this is a better lower bound than |s(K)/2|, where s(K) is the Rasmussen s invariant defined by the Bar-Natan spectral sequence.
Keywords
Cite
@article{arxiv.1710.07874,
title = {The Bar-Natan homology and unknotting number},
author = {Akram Alishahi},
journal= {arXiv preprint arXiv:1710.07874},
year = {2019}
}
Comments
13 pages