From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/5301 Path: news.gmane.org!not-for-mail From: Ross Street Newsgroups: gmane.science.mathematics.categories Subject: Re: Question on adjoints Date: Sat, 28 Nov 2009 21:59:59 +1100 Message-ID: References: Reply-To: Ross Street NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 (Apple Message framework v936) Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1259451484 848 80.91.229.12 (28 Nov 2009 23:38:04 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 28 Nov 2009 23:38:04 +0000 (UTC) To: Categories list Original-X-From: categories@mta.ca Sun Nov 29 00:37:57 2009 Return-path: Envelope-to: gsmc-categories@m.gmane.org Original-Received: from mailserv.mta.ca ([138.73.1.1]) by lo.gmane.org with esmtp (Exim 4.50) id 1NEWrV-0002b0-CC for gsmc-categories@m.gmane.org; Sun, 29 Nov 2009 00:37:57 +0100 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.61) (envelope-from ) id 1NEWD0-0005MX-K6 for categories-list@mta.ca; Sat, 28 Nov 2009 18:56:06 -0400 Original-Sender: categories@mta.ca Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:5301 Archived-At: On 20/11/2009, at 10:25 AM, claudio pisani wrote: > this is a remark about the very first proposition in the "elephant", > followed by some questions. > Lemma 1.1.1 says: > > If F is left adjoint to G : D --> C and there is a natural > isomorphism FG --> 1_D (not necessarily the counit), then G is full > and faithful. For anyone interested, I have put a string proof of this at . ==Ross [For admin and other information see: http://www.mta.ca/~cat-dist/ ]