From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/5570 Path: news.gmane.org!not-for-mail From: William Boshuck Newsgroups: gmane.science.mathematics.categories Subject: Re: Logical consequences of descent theory Date: Fri, 12 Feb 2010 10:01:26 -0500 Message-ID: References: Reply-To: William Boshuck NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1266072629 8101 80.91.229.12 (13 Feb 2010 14:50:29 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 13 Feb 2010 14:50:29 +0000 (UTC) To: categories@mta.ca Original-X-From: categories@mta.ca Sat Feb 13 15:50:27 2010 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 4.69) (envelope-from ) id 1NgJKE-0000Er-JE for gsmc-categories@m.gmane.org; Sat, 13 Feb 2010 15:50:26 +0100 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.61) (envelope-from ) id 1NgIq4-0006ik-1i for categories-list@mta.ca; Sat, 13 Feb 2010 10:19:16 -0400 Content-Disposition: inline In-Reply-To: Original-Sender: categories@mta.ca Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:5570 Archived-At: In connnection with the descent theorem of Marek for pretoposes, the papers by Moerdijk and Vermeulen should be mentioned: Proper maps of toposes, Memoirs of the AMS, Vol 705 (2000). Proof of a conjecture of Pitts, Volume 143, Number 1 (1999), pp. 329-338 Descent theory has been a kind of definability theory from the beginning, I think. See, e.g., Andre Weil, The Field of Definition of a Variety, American Journal of Mathematics, Vol. 78, No. 3 (Jul., 1956), pp. 509-524. -wb [For admin and other information see: http://www.mta.ca/~cat-dist/ ]