Signature and crossing number of links

Kai Ishihara; Kei Okada; Koya Shimokawa

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arXiv · 2410.00445

Signature and crossing number of links

Kai Ishihara·Kei Okada·Koya Shimokawa

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Abstract

This paper investigates the relationship between the signature and the crossing number of knots and links. We refine existing theorems and provide a comprehensive classification of links with specific properties, particularly those with signatures that deviate by a fixed amount from their crossing numbers. The main results include the identification of all links for which the sum of the signature and crossing number equals 2, which are shown to be closures of positive 3-braids. Additionally, we explore the implications of these findings in the context of band surgeries and their applications to vortex knots and DNA topology.

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BibTeX RIS

Kai Ishihara, Kei Okada, Koya Shimokawa. 2024-10-01. Signature and crossing number of links. https://arxiv.org/abs/2410.00445

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