From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/7345 Path: news.gmane.org!not-for-mail From: "Paul Taylor" Newsgroups: gmane.science.mathematics.categories Subject: regular monos of groups Date: Fri, 22 Jun 2012 08:19:05 +0100 Message-ID: References: Reply-To: "Paul Taylor" NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain;charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable X-Trace: dough.gmane.org 1340360137 16217 80.91.229.3 (22 Jun 2012 10:15:37 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Fri, 22 Jun 2012 10:15:37 +0000 (UTC) To: categories@mta.ca Original-X-From: majordomo@mlist.mta.ca Fri Jun 22 12:15:36 2012 Return-path: Envelope-to: gsmc-categories@m.gmane.org Original-Received: from smtpx.mta.ca ([138.73.1.80]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Si0tr-0002YM-MU for gsmc-categories@m.gmane.org; Fri, 22 Jun 2012 12:15:35 +0200 Original-Received: from mlist.mta.ca ([138.73.1.63]:50214) by smtpx.mta.ca with esmtp (Exim 4.77) (envelope-from ) id 1Si0tR-0007ep-7g; Fri, 22 Jun 2012 07:15:09 -0300 Original-Received: from majordomo by mlist.mta.ca with local (Exim 4.71) (envelope-from ) id 1Si0tQ-0004Zw-Is for categories-list@mlist.mta.ca; Fri, 22 Jun 2012 07:15:08 -0300 In-Reply-To: Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:7345 Archived-At: Mike Barr said > Somewhere I have seen a proof that all monics in the category of groups > are regular. Somebody asked this question a while back on MathOverflow and I gave the following proof, which is both constructive and more explicit than the replies that have been given here. http://mathoverflow.net/questions/41208/are-all-group-monomorphisms-regular-constructively/46054#46054 Paul Taylor [For admin and other information see: http://www.mta.ca/~cat-dist/ ]