From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/9669 Path: news.gmane.org!.POSTED!not-for-mail From: Andrew Pitts Newsgroups: gmane.science.mathematics.categories Subject: Sheaf terminology question Date: Fri, 13 Jul 2018 15:10:05 +0100 Message-ID: Reply-To: Andrew Pitts NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 (Mac OS X Mail 11.4 \(3445.8.2\)) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1531742909 2345 195.159.176.226 (16 Jul 2018 12:08:29 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 16 Jul 2018 12:08:29 +0000 (UTC) To: categories Original-X-From: majordomo@mlist.mta.ca Mon Jul 16 14:08:25 2018 Return-path: Envelope-to: gsmc-categories@m.gmane.org Original-Received: from smtp2.mta.ca ([198.164.44.40]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ff2Ii-0000VQ-HW for gsmc-categories@m.gmane.org; Mon, 16 Jul 2018 14:08:24 +0200 Original-Received: from mlist.mta.ca ([138.73.1.63]:33829) by smtp2.mta.ca with esmtp (Exim 4.80) (envelope-from ) id 1ff2KL-00066Y-6F; Mon, 16 Jul 2018 09:10:05 -0300 Original-Received: from majordomo by mlist.mta.ca with local (Exim 4.71) (envelope-from ) id 1ff2Jj-0001fZ-UA for categories-list@mlist.mta.ca; Mon, 16 Jul 2018 09:09:27 -0300 Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:9669 Archived-At: Given a coverage on a small category, the condition for a Set-valued = presheaf on the category to be a sheaf has an existence part and a = uniqueness part. If only the uniqueness part holds, one says that the = presheaf is separated. Is there a name out there for presheaves that = only satisfy the existence part of the sheaf condition? Andy Pitts [For admin and other information see: http://www.mta.ca/~cat-dist/ ]