From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/3647 Path: news.gmane.org!not-for-mail From: "V. Schmitt" Newsgroups: gmane.science.mathematics.categories Subject: Re: terminology: dagger and involution Date: Thu, 01 Mar 2007 09:21:55 +0000 Message-ID: NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1241019432 9620 80.91.229.2 (29 Apr 2009 15:37:12 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:37:12 +0000 (UTC) To: categories Original-X-From: rrosebru@mta.ca Thu Mar 1 23:18:44 2007 -0400 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Thu, 01 Mar 2007 23:18:44 -0400 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.61) (envelope-from ) id 1HMy8G-0003El-Ub for categories-list@mta.ca; Thu, 01 Mar 2007 23:08:32 -0400 Original-Sender: cat-dist@mta.ca Precedence: bulk X-Keywords: X-UID: 1 Original-Lines: 47 Xref: news.gmane.org gmane.science.mathematics.categories:3647 Archived-At: John Baez wrote: >Marco wrote: > > > >>what you are calling a "dagger-category", i.e. >> >> a category equipped with a contravariant involutive >> endofunctor, which is the identity on objects, >> >>has been called "a category with involution", at least from Burgin >>1969 to Lambek 2001. "Involutive category" has also been used, if >>less. >> >>I think it would be better to come back to the old term, which is >>meaningful, translatable, and old. >> >> > >There's also a body of work, mainly from mathematical physics, that >calls these categories "star-categories". > >But, by now there's enough literature using the term "dagger-categories" >that the genie is out of the bottle. > >Best, >jb > > > > > > Dear John, just my view: this is not a good argument. I do not know about these dagger categories though i read about the compact closed ones. So may be I miss the point but, if this is the case, why introducing a new terminology if the concepts are not? That just creates confusion. Best, Vincent