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

Pajitnov, Andrei¹

¹Laboratoire Mathématiques Jean Leray UMR 6629, Université de Nantes, Faculté des Sciences, 2, rue de la Houssinière, 44072 Nantes Cedex, France

Algebraic and Geometric Topology, Tome 10 (2010) no. 2, pp. 627-635

Résumé

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.

Détail

DOI : 10.2140/agt.2010.10.627

Keywords: tunnel number, Morse–Novikov number, Alexander polynomial

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