From: John Baez <john.c.baez@gmail.com>
To: categories <categories@mta.ca>
Subject: Re: forms
Date: Thu, 14 Jan 2010 18:51:00 -0800 [thread overview]
Message-ID: <E1NVvAD-0002tQ-2T@mailserv.mta.ca> (raw)
Al Vilcius wrote:
> > For example, in vector spaces (k-mod)
>
> there are the usual bijective correspondences:
> >
> > X tensor Y ---> Z linear in k-mod
> > ____________________________________
> >
> > X cartesian Y ---> Z bilinear
> >
>
Andrej Bauer replied:
>
> I always understood the correspondence between the first and the second
> line as saying "don't talk about bilinear maps on
> products--talk about linear maps on tensor products instead".
>
Or, you can reverse your attitude and say "don't talk about linear maps out
of tensor products--talk about arrows in the *multicategory* of multilinear
maps'.
You may not like multicategories - but as Toby said, they're there when you
want them, waiting with the kind of patience that only mathematical objects
can muster:
http://ncatlab.org/nlab/show/multicategory
http://en.wikipedia.org/wiki/Multicategory
Best,
jb
[For admin and other information see: http://www.mta.ca/~cat-dist/ ]
next reply other threads:[~2010-01-15 2:51 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-15 2:51 John Baez [this message]
-- strict thread matches above, loose matches on Subject: below --
2010-01-19 19:27 forms Al Vilcius
2010-01-13 17:18 forms Al Vilcius
2010-01-14 15:19 ` forms Andrej Bauer
2010-01-14 17:15 ` forms Toby Bartels
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