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arXiv · 1207.2413

The unknotting number and classical invariants II

Abstract

In [BF12] the authors associated to a knot K an invariant n_R(K) which is defined using the Blanchfield form and which gives a lower bound on the unknotting number. In this paper we express n_R(K) in terms of Levine-Tristram signatures and nullities of K. In the proof we also show that the Blanchfield form with real coefficients is diagonalizable.

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Maciej Borodzik, Stefan Friedl. 2013-08-02. The unknotting number and classical invariants II. https://arxiv.org/abs/1207.2413

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