English

A minimality property for knots without Khovanov 2-torsion

Geometric Topology 2025-11-05 v1 Quantum Algebra

Abstract

A conjecture of Shumakovitch states that every nontrivial knot has 2-torsion in its Khovanov homology. We show that if a knot KK has no 2-torsion in its Khovanov homology, then the rank of its reduced Khovanov homology is minimal among all knots obtainable from KK by a proper rational tangle replacement. It follows, for example, that unknotting number 1 knots have 2-torsion in their Khovanov homology.

Keywords

Cite

@article{arxiv.2310.06163,
  title  = {A minimality property for knots without Khovanov 2-torsion},
  author = {Onkar Singh Gujral and Joshua Wang},
  journal= {arXiv preprint arXiv:2310.06163},
  year   = {2025}
}

Comments

3 pages