From: Ronnie Brown <ronnie.profbrown@btinternet.com>
To: Ondrej Rypacek <ondrej.rypacek@gmail.com>
Cc: categories@mta.ca
Subject: Re: double 2-categories
Date: Tue, 07 Dec 2010 14:13:25 +0000 [thread overview]
Message-ID: <E1PQ9wp-0006f3-VO@mlist.mta.ca> (raw)
In-Reply-To: <E1PPxIg-0005a7-3R@mlist.mta.ca>
I am not sure why there is the restriction to having 2-categories as
edge arrows. They could be double categories, perhaps. Would this then
be any more general than a 4-fold category?
A definition of n-fold category is given in
34. (with P.J. HIGGINS), ``The equivalence of $\infty$-groupoids and
crossed complexes'', {\em Cah. Top. G\'eom. Diff.} 22 (1981)
371-386.
and this also contains a definition of what was later called a globular
set, giving a notion of what we now call a strict globular n-category,
though the emphasis in the paper is on the groupoid case.
Ronnie
On 07/12/2010 12:59, Ondrej Rypacek wrote:
> Dear all,
>
> Is there a standard reference for what could be called a double-2-category,
> by which I mean a double category where the categories of horizontal and
> vertical arrows are 2-categories ?
> It would be a special case of a "triple category", I guess, where
> there are objects, arrows in three directions, cells for each distinct
> pair of the directions, and cubes surrounded by cells.
>
>
> Many thanks,
> Ondrej
>
[For admin and other information see: http://www.mta.ca/~cat-dist/ ]
next prev parent reply other threads:[~2010-12-07 14:13 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-07 12:59 Ondrej Rypacek
2010-12-07 14:13 ` Ronnie Brown [this message]
2010-12-09 9:36 ` Ross Street
[not found] ` <4CFE4105.5020902@btinternet.com>
2010-12-07 16:08 ` Ondrej Rypacek
2010-12-07 18:35 ` Jeff Egger
[not found] ` <456981.42294.qm@web110605.mail.gq1.yahoo.com>
[not found] ` <16A709CA-BA0D-4E71-8994-F700356973D3@gmail.com>
2010-12-07 19:31 ` Ondrej Rypacek
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