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 10 crossings and unknotting number equal to one.
Original language | English (US) |
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Pages (from-to) | 705-745 |
Number of pages | 41 |
Journal | Topology |
Volume | 44 |
Issue number | 4 |
DOIs | |
State | Published - Jul 2005 |
All Science Journal Classification (ASJC) codes
- Geometry and Topology
Keywords
- Alternating knots
- Floer homology
- Goeritz matrix
- Unknotting number one