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From: Ronnie Brown <ronnie.profbrown@btinternet.com>
To: "Jonathan CHICHE 齊正航" <chichejonathan@gmail.com>
Cc: Categories list <categories@mta.ca>,
	Marco Grandis <grandis@dima.unige.it>
Subject: Re: Simplicial versus (cubical with connections)
Date: Wed, 14 Sep 2011 11:04:39 +0100	[thread overview]
Message-ID: <E1R3vIH-0003YG-M3@mlist.mta.ca> (raw)
In-Reply-To: <33D5C4F9-416F-47E2-9CB3-C0109F977475@gmail.com>

The result of Maltsiniotis referred to by Jonathan is very welcome.  But 
I wonder if there is still a problem with cubical sets with connection:

the geometric realisation of a simplicial group is, in a convenient 
category, a topological group, because of the homeomorphism

f: |K \times Y| \to |K| \times |Y| .

However in the case of cubical sets with connections this map f is a 
homotopy equivalence but it seems is not a homeomorphism (?).  As 
Grothendieck wrote: `homotopically speaking' that is not a problem!

For homotopies and higher homotopies cubes are nice and easy because of 
the basic formula

I^m \times I^n = I^{m+n}.

This leads to monoidal closed structures on strict cubical higher 
categories and groupoids.

For a basic discussion of other issues such as algebraic inverses to 
subdivision and commutative cubes  I refer to my 2009  Liverpool seminar 
on`What is and what should be `Higher dimensional group theory'?'

http://pages.bangor.ac.uk/~mas010/pdffiles/liverpool-beamer-handout.pdf

Ronnie




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       reply	other threads:[~2011-09-14 10:04 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <33D5C4F9-416F-47E2-9CB3-C0109F977475@gmail.com>
2011-09-14 10:04 ` Ronnie Brown [this message]
     [not found] ` <E1R4GgT-0007ej-Hq@mlist.mta.ca>
2011-09-15 19:06   ` Urs Schreiber
2011-09-16 13:24     ` Fernando Muro
2011-10-18 13:27       ` Urs Schreiber
2011-10-19  8:35         ` Marco Grandis
2011-10-19 17:09           ` Vaughan Pratt
2011-10-20 10:39             ` Ronnie Brown
2011-10-29  1:08 Simplicial versus (cubical) " F William Lawvere
  -- strict thread matches above, loose matches on Subject: below --
2011-10-22 13:07 Simplicial versus (cubical " Todd Trimble
2011-10-26 21:27 ` F. William Lawvere
     [not found] <E1RGrPh-0003WW-KS@mlist.mta.ca>
2011-10-20 22:08 ` Ross Street
2011-09-12  0:30 Simplicial groups are Kan Michael Barr
2011-09-12  9:35 ` Ronnie Brown
2011-09-13 15:12   ` Simplicial versus (cubical with connections) Marco Grandis
     [not found]   ` <BDF51495-03DB-4725-8372-094AD1608A11@dima.unige.it>
2011-09-13 16:58     ` Ronnie Brown
2011-09-14  7:08       ` Jonathan CHICHE 齊正航

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