From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/6326 Path: news.gmane.org!not-for-mail From: "Prof. Peter Johnstone" Newsgroups: gmane.science.mathematics.categories Subject: terminology for simplicial sets Date: Tue, 19 Oct 2010 11:54:54 +0100 (BST) Message-ID: Reply-To: "Prof. Peter Johnstone" NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: TEXT/PLAIN; format=flowed; charset=US-ASCII X-Trace: dough.gmane.org 1287493583 16531 80.91.229.12 (19 Oct 2010 13:06:23 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Tue, 19 Oct 2010 13:06:23 +0000 (UTC) To: Categories mailing list Original-X-From: majordomo@mlist.mta.ca Tue Oct 19 15:06:21 2010 Return-path: Envelope-to: gsmc-categories@m.gmane.org Original-Received: from smtpx.mta.ca ([138.73.1.114]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1P8BtU-0007Di-0E for gsmc-categories@m.gmane.org; Tue, 19 Oct 2010 15:06:20 +0200 Original-Received: from mlist.mta.ca ([138.73.1.63]:58879) by smtpx.mta.ca with esmtp (Exim 4.71) (envelope-from ) id 1P8BsI-0007VR-Mq; Tue, 19 Oct 2010 10:05:06 -0300 Original-Received: from majordomo by mlist.mta.ca with local (Exim 4.71) (envelope-from ) id 1P8BsE-0001Uh-S7 for categories-list@mlist.mta.ca; Tue, 19 Oct 2010 10:05:02 -0300 Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:6326 Archived-At: In something I've been thinking about recently, the condition on a simplicial set that all faces of non-degenerate simplices are non-degenerate seems to play a significant role. Does anyone know whether this condition has been considered previously, and if so whether it has a standard name? The condition is of course satisfied by those simplicial sets which are derived from simplicial complexes in the standard way, but it's more general: it allows the possibility that two (formally) different faces of a non-degenerate simplex might coincide, as long as they're not degenerate. Peter Johnstone [For admin and other information see: http://www.mta.ca/~cat-dist/ ]