From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/7197 Path: news.gmane.org!not-for-mail From: Ohad Kammar Newsgroups: gmane.science.mathematics.categories Subject: Pullbacks of a family of arrows Date: Wed, 8 Feb 2012 20:29:08 +0000 Message-ID: Reply-To: Ohad Kammar NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 X-Trace: dough.gmane.org 1328798919 20234 80.91.229.3 (9 Feb 2012 14:48:39 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Thu, 9 Feb 2012 14:48:39 +0000 (UTC) To: Categories List Original-X-From: majordomo@mlist.mta.ca Thu Feb 09 15:48:37 2012 Return-path: Envelope-to: gsmc-categories@m.gmane.org Original-Received: from smtpx.mta.ca ([138.73.1.4]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1RvVIZ-0004Yb-BF for gsmc-categories@m.gmane.org; Thu, 09 Feb 2012 15:48:35 +0100 Original-Received: from mlist.mta.ca ([138.73.1.63]:57518) by smtpx.mta.ca with esmtp (Exim 4.77) (envelope-from ) id 1RvVHh-0006tT-No; Thu, 09 Feb 2012 10:47:41 -0400 Original-Received: from majordomo by mlist.mta.ca with local (Exim 4.71) (envelope-from ) id 1RvVHg-0005jO-QT for categories-list@mlist.mta.ca; Thu, 09 Feb 2012 10:47:40 -0400 Content-Disposition: inline Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:7197 Archived-At: What is the standard name for the limit of the diagram consisting of a morphism f : A --> C and an I-indexed family of morphisms g_i : B_i --> C where I is a set? This is a slight generalisation of pullbacks. I am really interested in the terminology for the following notion: A class of morphisms M is stable under such generalised pullbacks if, for all such limiting cones a : P --> A b_i : P --> B_i if g_i are all in M, then so is the morphism a : P --> A (This is a slight generalisation of stability of M under pullbacks.) Thanks, Ohad. -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. [For admin and other information see: http://www.mta.ca/~cat-dist/ ]