Talk:Knot invariant

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Mathematics rating: Stub Class Mid Priority  Field: Topology

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. --C S 09:07, Nov 10, 2004 (UTC)
Yes, but n-colourability is easier to understand. --Dylan Thurston 22:05, 8 May 2005 (UTC)
    • 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". --C S 09:07, Nov 10, 2004 (UTC)
    • 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?


--C S 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.

The statement was corrected 2006 August 27. -- Chuck 13:24, 14 June 2007 (UTC)