English

Characterising slopes for hyperbolic knots and Whitehead doubles

Geometric Topology 2026-03-04 v3

Abstract

A slope p/qQp/q \in \mathbb{Q} is characterising for a knot KS3K \subset \mathbb{S}^3 if the oriented homeomorphism type of the manifold SK3(p/q)\mathbb{S}^3_K(p/q) obtained by Dehn surgery of slope p/qp/q on KK uniquely determines the knot KK. We combine analysis of JSJ decompositions with techniques involving lengths of shortest geodesics to find explicit conditions for a slope to be characterising for KK in the case where KK is any hyperbolic knot or any satellite knot by a hyperbolic pattern. Assuming that the list of 2-cusped orientable hyperbolic 3-manifolds obtained using the computer programme SnapPy is complete up to a certain point, we use hyperbolic volume inequalities to generate a refinement for the special case of Whitehead doubles. We also construct pairs of multiclasped Whitehead doubles of double twist knots for which 1/q1/q is a non-characterising slope.

Keywords

Cite

@article{arxiv.2304.04349,
  title  = {Characterising slopes for hyperbolic knots and Whitehead doubles},
  author = {Laura Wakelin},
  journal= {arXiv preprint arXiv:2304.04349},
  year   = {2026}
}

Comments

28 pages, 8 figures, 5 tables. Revised title. Accepted for publication in Algebraic & Geometric Topology

R2 v1 2026-06-28T09:56:37.106Z