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An Explicit Computation of the Blanchfield Pairing for Arbitrary Links

Published online by Cambridge University Press:  20 November 2018

Anthony Conway*
Affiliation:
Université de Genève, Section de mathématiques, 2-4 rue du Lièvre, 1211 Genève, Switzerland, e-mail: [email protected]
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Abstract

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Given a link $L$, the Blanchfield pairing $\text{Bl(}L\text{)}$ is a pairing that is defined on the torsion submodule of the Alexander module of $L$. In some particular cases, namely if $L$ is a boundary link or if the Alexander module of $L$ is torsion, $\text{Bl(}L\text{)}$ can be computed explicitly; however no formula is known in general. In this article, we compute the Blanchfield pairing of any link, generalizing the aforementioned results. As a corollary, we obtain a new proof that the Blanchfield pairing is Hermitian. Finally, we also obtain short proofs of several properties of $\text{Bl(}L\text{)}$.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2018

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