From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/8108 Path: news.gmane.org!not-for-mail From: Mike Stay Newsgroups: gmane.science.mathematics.categories Subject: Re: Isbell envelope Date: Mon, 12 May 2014 09:19:27 -0600 Message-ID: References: Reply-To: Mike Stay NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 X-Trace: ger.gmane.org 1399979789 7551 80.91.229.3 (13 May 2014 11:16:29 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 13 May 2014 11:16:29 +0000 (UTC) Cc: categories To: Richard Garner Original-X-From: majordomo@mlist.mta.ca Tue May 13 13:16:24 2014 Return-path: Envelope-to: gsmc-categories@m.gmane.org Original-Received: from smtp3.mta.ca ([138.73.1.186]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1WkAh5-0000NH-JI for gsmc-categories@m.gmane.org; Tue, 13 May 2014 13:16:23 +0200 Original-Received: from mlist.mta.ca ([138.73.1.63]:58089) by smtp3.mta.ca with esmtp (Exim 4.80) (envelope-from ) id 1WkAgR-00022I-4p; Tue, 13 May 2014 08:15:43 -0300 Original-Received: from majordomo by mlist.mta.ca with local (Exim 4.71) (envelope-from ) id 1WkAgP-0000x3-4Y for categories-list@mlist.mta.ca; Tue, 13 May 2014 08:15:41 -0300 In-Reply-To: Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:8108 Archived-At: Isbell called it the "double envelope". http://www.ams.org/journals/bull/1966-72-04/S0002-9904-1966-11541-0/S0002-9904-1966-11541-0.pdf On Sun, May 11, 2014 at 10:09 PM, Richard Garner wrote: > Dear categorists, > > One of the more folklorish constructions in category theory is that of > the Isbell envelope. The folklorishness, in this case, seems to be so > severe that I cannot find mention made of it in any published article at > all (though there are several to the related notion of Isbell > conjugacy). I am writing, therefore, in the hope that this is only due > to my own poor knowledge of the literature, and that some other reader > of this list may be able to put me to rights. > > Richard > [For admin and other information see: http://www.mta.ca/~cat-dist/ ]