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Involutions of knots that fix unknotting tunnels

David Futer
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Abstract

Let K be a knot that has an unknotting tunnel tau. We prove that K admits a strong involution that fixes tau pointwise if and only if K is a two-bridge knot and tau its upper or lower tunnel.

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David Futer. 2004-01-29. Involutions of knots that fix unknotting tunnels. https://doi.org/10.1142/s0218216507005506

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