Knots with unknotting number one and Heegaard Floer homology

Peter Ozsvath; Zoltan Szabo

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arXiv · math/0401426

Knots with unknotting number one and Heegaard Floer homology

Peter Ozsvath·Zoltan Szabo

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Abstract

We use Heegaard Floer homology to give obstructions to unknotting a knot with a single crossing change. These restrictions are particularly useful in the case where the knot in question is alternating. As an example, we use them to classify all knots with crossing number less than or equal to nine and unknotting number equal to one. We also classify alternating knots with ten crossings and unknotting number equal to one.

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BibTeX RIS

Peter Ozsvath, Zoltan Szabo. 2005-03-15. Knots with unknotting number one and Heegaard Floer homology. https://arxiv.org/abs/math/0401426

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