## Algebraic & Geometric Topology

### The length of unknotting tunnels

#### Abstract

We show there exist tunnel number one hyperbolic $3$–manifolds with arbitrarily long unknotting tunnel. This provides a negative answer to an old question of Colin Adams.

#### Article information

Source
Algebr. Geom. Topol., Volume 10, Number 2 (2010), 637-661.

Dates
Accepted: 13 January 2010
First available in Project Euclid: 19 December 2017

https://projecteuclid.org/euclid.agt/1513715109

Digital Object Identifier
doi:10.2140/agt.2010.10.637

Mathematical Reviews number (MathSciNet)
MR2606795

Zentralblatt MATH identifier
1194.57021

Subjects
Primary: 57M50: Geometric structures on low-dimensional manifolds

#### Citation

Cooper, Daryl; Lackenby, Marc; Purcell, Jessica S. The length of unknotting tunnels. Algebr. Geom. Topol. 10 (2010), no. 2, 637--661. doi:10.2140/agt.2010.10.637. https://projecteuclid.org/euclid.agt/1513715109

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