Signatures of links in rational homology spheres

Jae Choon Cha; Ki Hyoung Ko

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Signatures of links in rational homology spheres

Jae Choon Cha·Ki Hyoung Ko

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Abstract

A theory of signatures for odd-dimensional links in rational homology spheres is studied via their generalized Seifert surfaces. The jump functions of signatures are shown invariant under appropriately generalized concordance and a special care is given to accommodate 1-dimensional links with mutual linking. Furthermore our concordance theory of links in rational homology spheres remains highly nontrivial after factoring out the contribution from links in integral homology spheres.

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Jae Choon Cha, Ki Hyoung Ko. 2001-09-20. Signatures of links in rational homology spheres. https://arxiv.org/abs/math/0108197

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