Khovanov homology and the cinquefoil

John A. Baldwin; Ying Hu; Steven Sivek

doi:10.4171/jems/1415

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arXiv · 2105.12102

Khovanov homology and the cinquefoil

John A. Baldwin·Ying Hu·Steven Sivek

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Abstract

We prove that Khovanov homology with coefficients in $\mathbb{Z}/2\mathbb{Z}$ detects the $(2,5)$ torus knot. Our proof makes use of a wide range of deep tools in Floer homology, Khovanov homology, and Khovanov homotopy. We combine these tools with classical results on the dynamics of surface homeomorphisms to reduce the detection question to a problem about mutually braided unknots, which we then solve with computer assistance.

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John A. Baldwin, Ying Hu, Steven Sivek. 2021-05-25. Khovanov homology and the cinquefoil. https://doi.org/10.4171/jems%2F1415

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