Talk:Knot invariant
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Moved from article:
- More needed. Suggestions:
- n-colourabilty
- This is a special case of quandles. Perhaps the quandles entry should be updated to make this connection clearer. --Chan-Ho Suh 09:07, Nov 10, 2004 (UTC)
- Yes, but n-colourability is easier to understand. --Dylan Thurston 22:05, 8 May 2005 (UTC)
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- the twist (I think that's the wrong term - I mean the one where you add together the crossings including signs - writhe, maybe)
- It sounds like you mean "writhe". --Chan-Ho Suh 09:07, Nov 10, 2004 (UTC)
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- for genus, we obviously need Seifert sufaces, which could really do with some pictures.
- braid index - probably needs an article on braids
- unknotting number
- linking number? Really a link invariant
- relationships between invariants
- Alexander polynomial
- Jones polynomial and generalisations
- homology of knots?
--Chan-Ho Suh 09:01, Nov 10, 2004 (UTC)
Some more invariants:
- Vassiliev or finite-type invariants
- knot energies: ropelength, etc.
--Dylan Thurston 22:05, 8 May 2005 (UTC)
[edit] Fary-Milnor theorem
This page says that the Fary-Milnor theorem is if and only if. However, the page for that theorem implies that only one direction holds. I don't know enough about the theorem to be comfortable touching either page, though.