From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/4799 Path: news.gmane.org!not-for-mail From: Colin McLarty Newsgroups: gmane.science.mathematics.categories Subject: Re: terminology in definitions of limits Date: Tue, 20 Jan 2009 12:15:54 -0500 Message-ID: Reply-To: Colin McLarty NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1241020180 14888 80.91.229.2 (29 Apr 2009 15:49:40 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:49:40 +0000 (UTC) To: categories@mta.ca Original-X-From: rrosebru@mta.ca Tue Jan 20 19:30:07 2009 -0400 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Tue, 20 Jan 2009 19:30:07 -0400 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.61) (envelope-from ) id 1LPPzk-0003yw-PX for categories-list@mta.ca; Tue, 20 Jan 2009 19:26:56 -0400 Content-Language: en Content-Disposition: inline Original-Sender: categories@mta.ca Precedence: bulk X-Keywords: X-UID: 20 Original-Lines: 33 Xref: news.gmane.org gmane.science.mathematics.categories:4799 Archived-At: I often call them "test objects" in talking with students (by analogy with "test particles" in General Relativity). I don't think I have ever done it in print. But I did use "T" as the typical name of such an object in my book. I am curious to know what others think. best, Colin ----- Original Message ----- From: categories@mta.ca Date: Tuesday, January 20, 2009 11:01 am Subject: categories: terminology in definitions of limits To: categories@mta.ca > Folk, > > Each definition of a limit which I've > seen contains something I would describe > as a "probe object" or "test object". The > definition of map object in L&S page 313 > for example, has X with a criterion asserted > for every object X in the category. > > Is there any sense in my terminology? > > Thanks, ... Peter E. > > > >