Computation of the knot symmetric quandle and its application to the plat index of surface-links

Jumpei Yasuda

doi:10.1142/s0218216524500056

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arXiv · 2308.14488

Computation of the knot symmetric quandle and its application to the plat index of surface-links

Jumpei Yasuda

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Abstract

A surface-link is a closed surface embedded in the 4-space, possibly disconnected or non-orientable. Every surface-link can be presented by the plat closure of a braided surface, which we call a plat form presentation. The knot symmetric quandle of a surface-link $F$ is a pair of a quandle and a good involution determined from $F$. In this paper, we compute the knot symmetric quandle for surface-links using a plat form presentation. As an application, we show that for any integers $g \geq 0$ and $m \geq 2$, there exists infinitely many distinct surface-knots of genus $g$ whose plat indices are $m$.

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Jumpei Yasuda. 2023-08-28. Computation of the knot symmetric quandle and its application to the plat index of surface-links. https://doi.org/10.1142/s0218216524500056

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