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From: "Joyal, André" <joyal.andre@uqam.ca>
To: "Andrej Bauer" <andrej.bauer@andrej.com>,
	       "categories list" <categories@mta.ca>
Subject: What else do simplicial sets classify?
Date: Sun, 1 Aug 2010 13:14:39 -0400	[thread overview]
Message-ID: <E1OfuAI-0006lW-BP@mlist.mta.ca> (raw)
In-Reply-To: <E1OfK1M-0001vZ-7t@mlist.mta.ca>

Dear Andrej,

I do not know what you mean by a bounded linear order.

But I know that the topos of simplicial sets
is classifying strict intervals.

(an interval [a,b] is strict if its endpoint a and b are different)

  bounded linear orders = strict intervals?

Best, 
André

-------- Message d'origine--------
De: Andrej Bauer [mailto:andrej.bauer@andrej.com]
Date: sam. 31/07/2010 03:55
À: categories list
Objet : categories: What else do simplicial sets classify?
 
The presheaf category of simplicial sets is the classifying topos for
the theory L of a bounded linear order.

In general, there could be other theories which are "Morita
equivalent" to L in the sense that their classifying toposes are
equivalent to simplicial sets. Are any such known, preferably
occurring in nature?

With kind regards,

Andrej

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


      parent reply	other threads:[~2010-08-01 17:14 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-07-31  7:55 Andrej Bauer
2010-08-01 14:16 ` Prof. Peter Johnstone
2010-08-08 12:11   ` "etirement morphique" soloviev
2011-10-02 21:10   ` diagrams in computer algebra Sergei SOLOVIEV
2011-10-03 18:02     ` Michael J Healy
2011-10-04 16:04       ` Eduardo J. Dubuc
     [not found]       ` <CA+0XtC_e0MsZ_a6WYPCWO=FPH15ULwa_9Lcv+zduJaK8HtKSPA@mail.gmail.com>
2011-10-12 21:47         ` Michael J Healy
     [not found]       ` <CA+0XtC_Soy9nyC=OLaSi88WHow_vKxQ+=aCadA2RyrAD+WNUyw@mail.gmail.com>
2011-10-12 21:53         ` Michael J Healy
2010-08-01 17:14 ` Joyal, André [this message]

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