Cusp shape and tunnel number

Vinh Dang; Jessica S. Purcell

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arXiv · 1711.03693

Cusp shape and tunnel number

Vinh Dang·Jessica S. Purcell

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Abstract

We show that the set of cusp shapes of hyperbolic tunnel number one manifolds is dense in the Teichmuller space of the torus. A similar result holds for tunnel number n manifolds. As a consequence, for fixed n, there are infinitely many hyperbolic tunnel number n manifolds with at most one exceptional Dehn filling. This is in contrast to large volume Berge knots, which are tunnel number one manifolds, but with cusp shapes converging to a single point in Teichmuller space.

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Vinh Dang, Jessica S. Purcell. 2018-07-24. Cusp shape and tunnel number. https://arxiv.org/abs/1711.03693

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