Alphabeta MathThe tau invariant and four-ball genus — Examples and Counterexamples
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2 · Logical flowchart
3 · Items
Example
Tau of the unknot and trefoils from filtered staircases
Counterexample
Vanishing tau does not imply smooth sliceness
Sources
- Jennifer Hom, A survey on Heegaard Floer homology and concordance
- Peter S. Ozsvath and Zoltan Szabo, Knot Floer homology and the four-ball genus
- Peter S. Ozsvath, Andras I. Stipsicz, and Zoltan Szabo, Grid Homology for Knots and Links
- Matthew Hedden and Philip Ording, The Ozsvath-Szabo and Rasmussen concordance invariants are not equal
- Jacob Rasmussen, Khovanov homology and the slice genus