Strongly quasipositive links with braid index 3 have positive Conway polynomial

Marithania Silvero

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arXiv · 1503.00026

Strongly quasipositive links with braid index 3 have positive Conway polynomial

Marithania Silvero

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Abstract

Strongly quasipositive links are those links which can be seen as closures of positive braids in terms of band generators. In this paper we give a necessary condition for a link with braid index 3 to be strongly quasipositive, by proving that in that case it has positive Conway polynomial (that is, all its coefficients are non-negative). We also show that this result cannot be extended to a higher number of strands, as we provide a strongly quasipositive braid whose closure has non-positive Conway polynomial.

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Marithania Silvero. 2015-02-27. Strongly quasipositive links with braid index 3 have positive Conway polynomial. https://arxiv.org/abs/1503.00026

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