From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/5248 Path: news.gmane.org!not-for-mail From: Jacques Carette Newsgroups: gmane.science.mathematics.categories Subject: Differentiating folds? Date: Thu, 12 Nov 2009 10:54:34 -0500 Message-ID: Reply-To: Jacques Carette NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1258047361 21661 80.91.229.12 (12 Nov 2009 17:36:01 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 12 Nov 2009 17:36:01 +0000 (UTC) To: categories@mta.ca Original-X-From: categories@mta.ca Thu Nov 12 18:35:54 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 1N8daM-0005nQ-8P for gsmc-categories@m.gmane.org; Thu, 12 Nov 2009 18:35:54 +0100 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.61) (envelope-from ) id 1N8d7G-0001LA-9M for categories-list@mta.ca; Thu, 12 Nov 2009 13:05:50 -0400 Original-Sender: categories@mta.ca Precedence: bulk Xref: news.gmane.org gmane.science.mathematics.categories:5248 Archived-At: Has anyone ever worked out what it means (or should mean) for a homomorphism f:(A,a) -> (B,b) between F-algebras to be differentiable? Analogies to other settings in which derivatives can be defined makes me believe that the result should be a morphism f' between two F'-algebras. When F is a polynomial functor, napkin-level-mathematics indicates this isn't completely wrong... Jacques [For admin and other information see: http://www.mta.ca/~cat-dist/ ]