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A FAST ALGORITHM FOR CALCULATING S-INVARIANTS

Part of: Differential topology Low-dimensional topology

Published online by Cambridge University Press:  29 June 2020

DIRK SCHÜTZ
DIRK SCHÜTZ*
Affiliation:
Department of Mathematical Sciences, Durham University, Durham, UK, e-mail: dirk.schuetz@durham.ac.uk
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Abstract

We use the divide-and-conquer and scanning algorithms for calculating Khovanov cohomology directly on the Lee- or Bar-Natan deformations of the Khovanov complex to give an alternative way to compute Rasmussen s-invariants of knots. By disregarding generators away from homological degree 0, we can considerably improve the efficiency of the algorithm. With a slight modification, we can also apply it to a refinement of Lipshitz–Sarkar.

MSC classification

Primary: 57M25: Knots and links in $S^3$
Secondary: 57M27: Invariants of knots and 3-manifolds 57R56: Topological quantum field theories

Information

Type
Research Article
Information
Glasgow Mathematical Journal , Volume 63 , Issue 2 , May 2021 , pp. 378 - 399
Copyright
© The Author(s), 2020. Published by Cambridge University Press on behalf of Glasgow Mathematical Journal Trust

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