Patterns of the $V_2$-polynomial of knots

Stavros Garoufalidis; Shana Yunsheng Li

doi:10.1080/10586458.2026.2651081

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arXiv · 2409.03557

Patterns of the $V_2$-polynomial of knots

Stavros Garoufalidis·Shana Yunsheng Li

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Abstract

Recently, Kashaev and the first author constructed an $R$-matrix from a Nichols algebra with an automorphism, that leads, via the Reshetikhin--Turaev functor, to a multivariable polynomial invariant of knots. Applying this to a rank 2 Nichols algebra, results in a sequence $V_n$ of 2-variable knot polynomials with integer coefficients, the first polynomial been identified with the Links--Gould polynomial. In this note we present the results of the computation of the $V_n$-polynomials for $n=1,2,3,4$. This leads to the discovery of emerging patterns, including the genus bound for $V_2$ being an equality for all 352.2 million knots with at most $19$ crossings, as well as unexpected Conway mutations that seem undetected by the $V_n$-polynomials as well as by Heegaard Floer Homology and Khovanov Homology.

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Stavros Garoufalidis, Shana Yunsheng Li. 2024-09-05. Patterns of the $V_2$-polynomial of knots. https://doi.org/10.1080/10586458.2026.2651081

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