A user's guide to basic knot and link theory

A. Skopenkov

doi:10.1090/conm/772

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arXiv · 2001.01472

A user's guide to basic knot and link theory

A. Skopenkov

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Abstract

This paper is expository and is accessible to students. We define simple invariants of knots or links (linking number, Arf-Casson invariants and Alexander-Conway polynomials) motivated by interesting results whose statements are accessible to a non-specialist or a student. The simplest invariants naturally appear in an attempt to unknot a knot or unlink a link. Then we present certain `skein' recursive relations for the simplest invariants, which allow to introduce stronger invariants. We state the Vassiliev-Kontsevich theorem in a way convenient for calculating the invariants themselves, not only the dimension of the space of the invariants. No prerequisites are required; we give rigorous definitions of the main notions in a way not obstructing intuitive understanding.

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BibTeX RIS

A. Skopenkov. 2020-01-06. A user's guide to basic knot and link theory. https://doi.org/10.1090/conm%2F772

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