Geodesic
A new invariant of equivariant concordance and results on 2-bridge knots
Di Prisa, Alessio1 ; Framba, Giovanni2
1Scuola Normale Superiore di Pisa, Pisa, Italy
2Università di Pisa, Pisa, Italy
Algebraic and Geometric Topology, Tome 25 (2025) no. 2, pp. 1117-1132
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We study the equivariant concordance classes of 2-bridge knots and we prove that no 2-bridge knot is equivariantly slice. Finally, we introduce a new equivariant concordance invariant for strongly invertible knots. Using this invariant as an obstruction we strengthen the result on 2-bridge knots, proving that every 2-bridge knot has infinite order in the equivariant concordance group.

DOI : 10.2140/agt.2025.25.1117
Keywords: strongly invertible knot, 2-bridge knot, concordance, eta-function

Di Prisa, Alessio  1   ; Framba, Giovanni  2

1 Scuola Normale Superiore di Pisa, Pisa, Italy
2 Università di Pisa, Pisa, Italy 
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Di Prisa, Alessio; Framba, Giovanni. A new invariant of equivariant concordance and results on 2-bridge knots. Algebraic and Geometric Topology, Tome 25 (2025) no. 2, pp. 1117-1132. doi: 10.2140/agt.2025.25.1117

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