Talk:Bialgebra

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Mathematics rating:	Start Class	Low Priority	Field: Algebra
Please update this rating as the article progresses, or if the rating is inaccurate. Click to show/hide comments. Please add to or update the comments to suggest improvements to the article. Please add useful comments here--Cronholm144 07:09, 24 May 2007 (UTC)

Contents 1 Diagram too small 2 Misplaced arrows 3 This article has no introduction! 4 Antipode?

[edit] Diagram too small

the picture is way too small --MarSch 13:15, 20 October 2005 (UTC)

way way too small, I can't read it. linas 01:11, 6 March 2006 (UTC)

Better now? Dave Rosoff 01:02, 1 April 2006 (UTC)

much much better! I added some random text so that the figures wouldn't all flow into one big lmp, but have some whitespace. linas 01:48, 1 April 2006 (UTC)

The diagram was much too small and the improvement is marked. However, in the "Multiplication and Unit" diagram, the map

Delta : B x B ---> B should be Delta: B x B <--- B with the arrow in the other direction. Micah, no username, 2 April

Fixed, good catch! Dave Rosoff 06:21, 26 April 2006 (UTC)

[edit] Misplaced arrows

In the "Comultiplication and unit" diagram, shouldn't eta and eta x eta trade places? I mean, eta x eta : K x K --> B x B should be on the left, and eta : K --> B should be on the right (without changing the direction of the arrows), so that the digram states Delta(eta(k)) = eta(k) x eta(k) for all k in K. Damiano, no username, 5 January 2007

Agreed...if also the top thing says K x K = K instead of K = K x K. SeaRisk 03:32, 21 August 2007 (UTC)

[edit] This article has no introduction!

Hey there, you crazy kids; this hasn't got any introduction! It's pretty important to have one because they're good at sliding into the topics. Uxorion 14:04, 14 August 2007 (UTC)

[edit] Antipode?

I'm puzzled by where it says "Unit and counit (antipode)" -- I've never heard "antipode" used in this way. Isn't the antipode a thing that a bialgebra might or might not have (and if it does, it's a Hopf algebra)? SeaRisk 02:17, 21 August 2007 (UTC)

According to http://en.wikipedia.org/wiki/Hopf_algebra , you're right. An antipode is something a bialgebra may or may not have, and if it does it's a Hopf algebra.