A new invariant of equivariant concordance and results on 2-bridge knots

Alessio Di Prisa; Giovanni Framba

doi:10.2140/agt.2025.25.1117

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arXiv · 2303.08794

A new invariant of equivariant concordance and results on 2-bridge knots

Alessio Di Prisa·Giovanni Framba

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Abstract

We study the equivariant concordance classes of two-bridge knots, providing an easy formula to compute their butterfly polynomial, and we give two different proofs that no two-bridge knot is equivariantly slice. Finally, we introduce a new invariant of equivariant concordance for strongly invertible knots. Using this invariant as an obstruction we strengthen the result on two-bridge knots, proving that their equivariant concordance order is always infinite.

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Alessio Di Prisa, Giovanni Framba. 2023-03-15. A new invariant of equivariant concordance and results on 2-bridge knots. https://doi.org/10.2140/agt.2025.25.1117

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