From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/1189 Path: news.gmane.org!not-for-mail From: Kirill Mackenzie Newsgroups: gmane.science.mathematics.categories Subject: Re: universal property of tangent bundle Date: Mon, 2 Aug 1999 11:22:56 +0100 (BST) Message-ID: <199908021022.LAA18758@acms1.shef.ac.uk> NNTP-Posting-Host: main.gmane.org X-Trace: ger.gmane.org 1241017625 29885 80.91.229.2 (29 Apr 2009 15:07:05 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:07:05 +0000 (UTC) To: categories@mta.ca Original-X-From: cat-dist Mon Aug 2 14:20:42 1999 Original-Received: (from Majordom@localhost) by mailserv.mta.ca (8.9.3/8.9.3) id NAA12011 for categories-list; Mon, 2 Aug 1999 13:05:07 -0300 (ADT) X-Authentication-Warning: mailserv.mta.ca: Majordom set sender to cat-dist@mta.ca using -f Original-Sender: cat-dist@mta.ca Precedence: bulk Original-Lines: 43 Xref: news.gmane.org gmane.science.mathematics.categories:1189 Archived-At: In addition to Madame Ehresmann's references, there is in Spivak's Comprehensive Introduction... an abstract characterization of the tangent bundle ( removed from the main text in the second edition `due to the pressure of public distaste') Kirill Mackenzie > > Given an object M in the ``normal'' category of finitely dimensional > smooth manifolds Man (not in SDG sense), what it the universal property > of the tangent bundle TM? > > So far, I found only the following: > > For every manifold M there is a functor F:I -> Man0, where Man0 is > category of open areas in R^n and smooth mapping, such that M=Colim F, > F corresponding to the atlas on M and M is represented as a result of > gluing instances of R^n in the atlas. This functor can be trivially > modified (by multiplying its values on objects on R^n and modifying > morphisms appropriately) to get functor TF:I -> Man0, such that > TM=Colim TF. > > But this doesn't seem satisfactory because: > > 1. Construction of TF follows one particular construction of TM as a > set of triples (x,(U,f),h) where x \in U, (U,f) is in atlas and h \in > R^n with appropriate points identified. > > 2. I hope there should be universal construction with \pi: TM -> M as > universal arrow. > > 3. As tangent bundle is so ubiquitous there should be nice universal > property for it. > > With regards, > N. Danilov. > > > >