Spacious knots

Autumn E. Kent; Jessica S. Purcell

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arXiv · 1610.07731

Spacious knots

Autumn E. Kent·Jessica S. Purcell

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Abstract

We show that there exist hyperbolic knots in the 3-sphere such that the set of points of large injectivity radius in the complement take up the bulk of the volume. More precisely, given a finite volume hyperbolic manifold, for any bound R>0 on injectivity radius, consider the set of points with injectivity radius at least R; we call this the R-thick part of the manifold. We show that for any $\epsilon>0$, there exists a knot K in the 3-sphere so that the ratio of the volume of the R-thick part of the knot complement to the volume of the knot complement is at least $1-\epsilon$. As R approaches infinity, and as $\epsilon$ approaches zero, this gives a sequence of knots that is said to Benjamini--Schramm converge to hyperbolic space. This answers a question of Brock and Dunfield.

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Autumn E. Kent, Jessica S. Purcell. 2016-10-25. Spacious knots. https://arxiv.org/abs/1610.07731

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