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From: Ondrej Rypacek <ondrej.rypacek@gmail.com>
To: Ronnie Brown <ronnie.profbrown@btinternet.com>
Cc: categories@mta.ca
Subject: Re: double 2-categories
Date: Tue, 7 Dec 2010 16:08:13 +0000	[thread overview]
Message-ID: <E1PQ9xo-0006h0-UC@mlist.mta.ca> (raw)
In-Reply-To: <4CFE4105.5020902@btinternet.com>

Thanks! I think a special case of a 4-fold category is precisely what
I'm after, I just didn't know what are they called beyond the double
case.

Ondrej




On 7 December 2010 14:13, Ronnie Brown <ronnie.profbrown@btinternet.com> wrote:
> 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
>

[For admin and other information see: http://www.mta.ca/~cat-dist/ ]


  parent reply	other threads:[~2010-12-07 16:08 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
2010-12-09  9:36   ` Ross Street
     [not found] ` <4CFE4105.5020902@btinternet.com>
2010-12-07 16:08   ` Ondrej Rypacek [this message]
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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