## Algebraic & Geometric Topology

### On the tunnel number and the Morse–Novikov number of knots

Andrei Pajitnov

#### Abstract

Let $L$ be a link in $S3$; denote by $ℳN(L)$ the Morse–Novikov number of $L$ and by $t(L)$ the tunnel number of $L$. We prove that $ℳN(L)≤2t(L)$ and deduce several corollaries.

#### Article information

Source
Algebr. Geom. Topol., Volume 10, Number 2 (2010), 627-635.

Dates
Accepted: 5 January 2010
First available in Project Euclid: 19 December 2017

https://projecteuclid.org/euclid.agt/1513715108

Digital Object Identifier
doi:10.2140/agt.2010.10.627

Mathematical Reviews number (MathSciNet)
MR2606794

Zentralblatt MATH identifier
1196.57008

#### Citation

Pajitnov, Andrei. On the tunnel number and the Morse–Novikov number of knots. Algebr. Geom. Topol. 10 (2010), no. 2, 627--635. doi:10.2140/agt.2010.10.627. https://projecteuclid.org/euclid.agt/1513715108

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