From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/3650 Path: news.gmane.org!not-for-mail From: Dusko Pavlovic Newsgroups: gmane.science.mathematics.categories Subject: Re: dagger and involution Date: Fri, 02 Mar 2007 18:52:43 -0800 Message-ID: NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1241019434 9631 80.91.229.2 (29 Apr 2009 15:37:14 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:37:14 +0000 (UTC) To: categories Original-X-From: rrosebru@mta.ca Sat Mar 3 14:25:59 2007 -0400 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Sat, 03 Mar 2007 14:25:59 -0400 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.61) (envelope-from ) id 1HNYkb-0006Zb-SD for categories-list@mta.ca; Sat, 03 Mar 2007 14:14:33 -0400 Original-Sender: cat-dist@mta.ca Precedence: bulk X-Keywords: X-UID: 4 Original-Lines: 36 Xref: news.gmane.org gmane.science.mathematics.categories:3650 Archived-At: deciding whether the involution on a category should be written as a dagger or as a star sounds to me a bit like deciding whether a polynomial should be in x or in y. i worked with people who use the dagger, and didnt work with people who use the star, but it would be good if i could keep my options open. but anyway, denoting the math structures by the typographic symbols used in them sounds like an amusing idea. after a hundred years of progress in creating new structures, and metafonting new symbols for them, we'll probably be in possession of a fairly rich new language of hieroglyphs. -- dusko John Baez wrote: > [snip] > >I hope this is clear: "dagger-categories" are completely different >from "compact closed categories". We need *some* term for them; >we're just arguing about whether to call them "star-categories", >"dagger-categories", or "categories with involution". I like >"star-categories", because in analysis and quantum topology the >special case of "C*-categories" is very important. But, I doubt >we'll reach any sort of agreement! > >Best, >jb > > > > >