From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/6190 Path: news.gmane.org!not-for-mail From: Thomas Streicher Newsgroups: gmane.science.mathematics.categories Subject: Re: are fibrations evil? Date: Sat, 18 Sep 2010 15:48:29 +0200 Message-ID: References: Reply-To: Thomas Streicher NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: dough.gmane.org 1284906220 27518 80.91.229.12 (19 Sep 2010 14:23:40 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Sun, 19 Sep 2010 14:23:40 +0000 (UTC) Cc: categories@mta.ca To: Michael Shulman Original-X-From: majordomo@mlist.mta.ca Sun Sep 19 16:23:39 2010 Return-path: Envelope-to: gsmc-categories@m.gmane.org Original-Received: from smtpx.mta.ca ([138.73.1.138]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1OxKnq-0003GF-9I for gsmc-categories@m.gmane.org; Sun, 19 Sep 2010 16:23:38 +0200 Original-Received: from mlist.mta.ca ([138.73.1.63]:57106) by smtpx.mta.ca with esmtp (Exim 4.71) (envelope-from ) id 1OxKn3-0003A8-VU; Sun, 19 Sep 2010 11:22:49 -0300 Original-Received: from majordomo by mlist.mta.ca with local (Exim 4.71) (envelope-from ) id 1OxKn1-0004uw-Nq for categories-list@mlist.mta.ca; Sun, 19 Sep 2010 11:22:47 -0300 Content-Disposition: inline Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:6190 Archived-At: We seem to agree that paying attention to the non-kosher concept is at least very convenient. But what I do not see is a correspondence between kosher and non-kosher versions. If you start with a collection CC of 1-cells in a 2-cat like Cat and close it under equivalences thus obtaining CC' I don't see any way of reconstructing CC from CC' in a canonical way. Thomas [For admin and other information see: http://www.mta.ca/~cat-dist/ ]