From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/3108 Path: news.gmane.org!not-for-mail From: "Marta Bunge" Newsgroups: gmane.science.mathematics.categories Subject: Re: cracks and pots Date: Wed, 15 Mar 2006 07:23:28 -0500 Message-ID: References: <200603141956.k2EJu9625544@math-cl-n03.ucr.edu> Reply-To: marta.bunge@mcgill.ca NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; format=flowed X-Trace: ger.gmane.org 1241019099 7285 80.91.229.2 (29 Apr 2009 15:31:39 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:31:39 +0000 (UTC) To: categories@mta.ca Original-X-From: rrosebru@mta.ca Wed Mar 15 19:18:49 2006 -0400 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Wed, 15 Mar 2006 19:18:49 -0400 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.52) id 1FJfCK-0003LO-EL for categories-list@mta.ca; Wed, 15 Mar 2006 19:14:32 -0400 In-Reply-To: <200603141956.k2EJu9625544@math-cl-n03.ucr.edu> Original-Sender: cat-dist@mta.ca Precedence: bulk X-Keywords: X-UID: 54 Original-Lines: 146 Xref: news.gmane.org gmane.science.mathematics.categories:3108 Archived-At: Hi, I am relieved to learn (from the postings by David Yetter and John Baez) that Motl's blog on the issue of categories and string theory is based on 1) (Yetter) Motl's reluctance, as is the case with many string theorists, to refuse to learn category theory, and 2) (Baez) Motl's personal dislike of John Baez and of many other people, so that since Motl's personality is well-known, any damage will be minimal. I have also been reminded that 1) (Yetter) categorical ideas are central to several competitors of string theory, and that there is nothing cracked or crackpotish about them, and 2) (Baez) there is some serious work in the borderline of category theory and string theory as exemplified by several speakers at the StreetFest. I thank David and John for taking the trouble to respond in detail to what may have seem as a "provocation" on my part (well, perhaps it was...). But these informative responses do not address my main concern, which is one that others (publicly, as Eduardo Dubuc, but several others privately) have expressed to me following my posting. I was aiming at the fact that there is a certain trend within category theory (when did it start?) to consistely give center stage to anything that claims to have connections with physics (in particular string theory). Is this because (it is believed that) the state of category theory is now so poor (as "evidenced" by the lack of grants) that they (the organizers of meetings) want to repair this image at any cost? Also, by so doing, are we not becomeing vulnerable? Are we not pushing students to work on a certain area on the grounds that it is fashionable and likely to be funded, even if those students may lack the motivation and sound background knowledge? I feel that this is dangerous for category theory (and mathematics in general), as it may lead (is leading?) to narrow developments of any subject that is approached with these objectives in mind. I did point these concerns of mine already, in response to the posting by Robert MacDawson, whom I also thank for giving me the opportunity to make clearer what my real concerns are. On the subject of what constitutes good mathematics, Ronnie Brown has pointed out to me a beautiful expose (with Tim Porter) which you can find in www.bangor.ac.uk/r.brown/publar.html I urge you to read it. I end with a quote from the end of David Yetter's posting in reply to mine. "If (I suspect when) the string theory emperor turns out to have no clothes, category theory will suddenly become de rigeur in physics". I share his optimism. Most cordially, Marta Bunge ************************************************ Marta Bunge Professor Emerita Dept of Mathematics and Statistics McGill University 805 Sherbrooke St. West Montreal, QC, Canada H3A 2K6 Office: (514) 398-3810 Home: (514) 935-3618 marta.bunge@mcgill.ca http://www.math.mcgill.ca/bunge/ ************************************************ >From: "John Baez" >To: categories@mta.ca >Subject: categories: Re: cracks and pots >Date: Tue, 14 Mar 2006 11:56:09 -0800 (PST) > >Hi - > > > I just came across the following pages > > > > http://motls.blogspot.com/2004/11/category-theory-and-physics.html > > http://motls.blogspot.com/2004/11/this-week-208-analysis.html > > > > written by Lubos Motl, a physicist (string theorist). Some of you may >find > > these articles interesting and probably revealing. > > > > Are we category theorists as a whole going to quietly accept getting > > discredited by a minority of us presumably applying category theory to > > string theory? > >I can't tell if you're kidding. I'll assume you're not. > >There's nothing wrong with applying category theory to string theory. >The papers by Michael Douglas and Paul Aspinwall cited above by Motl >are some nice examples of using derived categories to study D-branes. > >Further examples: the Moore-Seiberg relations turn out to be little >more than the definition of a balanced monoidal category, and the >Segal-Moore axioms for open-closed topological strings are nicely >captured using category theory here: > >http://arxiv.org/abs/math.AT/0510664 > >There were a lot of nice talks on the borderline between category >theory and string theory at the Streetfest. > >Perhaps more to the point, Lubos Motl is famous for his heated >rhetoric. He doesn't like me, or anyone else who criticizes >string theory. The articles you mention above are mainly reactions >to my This Week's Finds. > >He's actually being very gentle - for him. He even says "the >role of category theory can therefore be described as a `progressive >direction' within string theory". > >I'm sure you'll all be pleased to know that. :-) > > > It is surely not too late to react and point out that this is > > not what (all of) category theory is about. > >I would urge everyone not to react - at least, not until they are >well aware of what a discussion with him is like. See his blog >and his comments on Peter Woit's blog if you don't understand what >I mean. For example: > >http://pitofbabel.org/blog/?p=51 > > > Please give a thought about what > > we, as a community, can urgently do to repair this damaging impression. > >Since Motl's personality is well known, any damage will be minimal. >I think we should relax and take it easy. > >Best, >jb > > > > > > > >