On the kinkiness of closed braids

Christian Bohr

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arXiv · math/0105224

On the kinkiness of closed braids

Christian Bohr

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Abstract

In this note, we prove a lower bound for the positive kinkiness of a closed braid which we then use to derive an estimate for the positive kinkiness of a link in terms of its Seifert system. As an application, we show that certain pretzel knots cannot be unknotted using only positive crossing changes. We also describe a subgroup of infinite rank in the smooth knot concordance group of which no element has a strongly quasipositive representative.

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Christian Bohr. 2001-05-27. On the kinkiness of closed braids. https://arxiv.org/abs/math/0105224

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