Talk:Bracket polynomial

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(24 sept 2006) I am having a hard time understanding what this sentence means: "from the undercrossing, the A is on the left hand side before the crossing, with the B on the other side; and the A is on the right hand side after coming out of the crossing, with the B on the left hand side". The use of "from", "left hand side" "other side" is very ambiguous. I think that a picture will help understand what is going on. Mathworld, on the other hand, is a bit technical on this. Can someone please add a picture in which A and B are placed and the new two knots of the recursive formula are drawn explicitely? Also, a couple of examples (trefoil...) would be nice to have. One last thing: on Wolfram I see a definition using A and A^(-1). Do I assume that we need to replace B here with A^(-1)? Thanks, Alberto — Preceding unsigned comment added by Albywind (talk • contribs) 09:01, 24 September 2006 (UTC)

I've fixed the article and added an image. I hope things are clearer now. Yes, in the usual defn of the bracket B should be replaced by A^{-1} in order that the bracket be single variable and have some nice properties. I believe the original version of the article was trying to explain the state sum formula. This formula can be obtained from the recursive definition in a simple way. If you like, you can figure it out and add it to the article :-) I don't have time for that right now, but I will be back eventually to add more stuff like that. --C S (Talk) 06:51, 22 January 2007 (UTC)