From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/7674 Path: news.gmane.org!not-for-mail From: "Eduardo J. Dubuc" Newsgroups: gmane.science.mathematics.categories Subject: correction Date: Fri, 26 Apr 2013 12:40:53 -0300 Message-ID: Reply-To: "Eduardo J. Dubuc" NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1367067532 11226 80.91.229.3 (27 Apr 2013 12:58:52 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 27 Apr 2013 12:58:52 +0000 (UTC) Cc: David Yetter , Categories list To: aleks0@gmail.com Original-X-From: majordomo@mlist.mta.ca Sat Apr 27 14:58:56 2013 Return-path: Envelope-to: gsmc-categories@m.gmane.org Original-Received: from smtp3.mta.ca ([138.73.1.186]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1UW4iN-0000qo-6m for gsmc-categories@m.gmane.org; Sat, 27 Apr 2013 14:58:55 +0200 Original-Received: from mlist.mta.ca ([138.73.1.63]:38566) by smtp3.mta.ca with esmtp (Exim 4.80) (envelope-from ) id 1UW4hC-0001V6-1V; Sat, 27 Apr 2013 09:57:42 -0300 Original-Received: from majordomo by mlist.mta.ca with local (Exim 4.71) (envelope-from ) id 1UW4hB-00084f-HZ for categories-list@mlist.mta.ca; Sat, 27 Apr 2013 09:57:41 -0300 Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:7674 Archived-At: Oops, forgot to say that furthermore, it should hold (for such a category) that when the non vertices of the cospan are equal, the "projections' in the commutative square can be taken to be equal. e.d. On 25/04/13 11:19, Aleks Kissinger wrote: > Oops, forgot to send to list. > > I think its actually a stronger property, but: perhaps cofiltered category? > > On 25 April 2013 04:14, David Yetter wrote: >> Is there an existing name in the literature for a category in which every cospan admits a completion to a commutative square? (Just that, no uniqueness, no universal >> properties required, just every cospan sits inside at least one commutative square). If so, what have such things been called? If not, does anyone have a poetic idea for a good name for >> such categories? >> >> Best Thoughts, >> David Yetter >> yes !, a cofiltered category is just a connected such category, Verdier's formulation, see Mac Lane's book if you don't like the SGA4. e.d. [For admin and other information see: http://www.mta.ca/~cat-dist/ ]