From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/3676 Path: news.gmane.org!not-for-mail From: "Dr. Cyrus F Nourani" Newsgroups: gmane.science.mathematics.categories Subject: Re: pullback ... Date: Wed, 07 Mar 2007 15:18:56 -0500 (EST) Message-ID: NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 8bit X-Trace: ger.gmane.org 1241019449 9732 80.91.229.2 (29 Apr 2009 15:37:29 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:37:29 +0000 (UTC) To: Original-X-From: rrosebru@mta.ca Wed Mar 7 19:33:14 2007 -0400 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Wed, 07 Mar 2007 19:33:14 -0400 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.61) (envelope-from ) id 1HP5cP-0004lT-Ba for categories-list@mta.ca; Wed, 07 Mar 2007 19:32:25 -0400 Original-Sender: cat-dist@mta.ca Precedence: bulk X-Keywords: X-UID: 30 Original-Lines: 36 Xref: news.gmane.org gmane.science.mathematics.categories:3676 Archived-At: Hello, there might be references on a paper I had written with
late Prof. Joseph Goguen U California and Oxford on that subject,
UCLA 1978.
When was that invented?
Cyrus







---------[ Received Mail Content ]----------

Subject : categories: Re: pullback ...

Date : Tue, 06 Mar 2007 21:09:33 -0500

From : "Fred E.J. Linton" <fejlinton@usa.net>

To : <categories@mta.ca>



Greetings!



As regards Peter Johnstone's query,



> ... does anyone out there know who invented the

> terms "pullback" and "pushout"? ...,



while I can't speak directly to the question of who invented those

terms, I do recall that, in the late '50s already, fiber bundles

were being "pulled back" along maps to their base spaces. And I can

still hear the late Serge Lang, bless his soul, intoning "pooll-back"

and "poosh-out" in his characeristic French accent, in Columbia

courses and seminars from the late '50s and early '60s.



So the terms were pretty well established (and pull-back, anyway,

pretty well motivated), at least at Columbia, that early.



Cheers,



-- Fred