The diameter of the set of boundary slopes of a knot

Ben Klaff; Peter B Shalen

doi:10.2140/agt.2006.6.1095

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The diameter of the set of boundary slopes of a knot

Ben Klaff·Peter B Shalen

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Abstract

Let K be a tame knot with irreducible exterior M(K) in a closed, connected, orientable 3--manifold Sigma such that pi_1(Sigma) is cyclic. If infinity is not a strict boundary slope, then the diameter of the set of strict boundary slopes of K, denoted d_K, is a numerical invariant of K. We show that either (i) d_K >= 2 or (ii) K is a generalized iterated torus knot. The proof combines results from Culler and Shalen [Comment. Math. Helv. 74 (1999) 530-547] with a result about the effect of cabling on boundary slopes.

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BibTeX RIS

Ben Klaff, Peter B Shalen. 2009-04-21. The diameter of the set of boundary slopes of a knot. https://doi.org/10.2140/agt.2006.6.1095

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