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From: Eduardo Julio Dubuc <edubuc@dm.uba.ar>
To: Thomas Streicher <streicher@mathematik.tu-darmstadt.de>
Cc: Categories list <categories@mta.ca>
Subject: Re: Giraud_Elementary_?
Date: Tue, 8 Nov 2016 12:13:39 -0500	[thread overview]
Message-ID: <E1c4Gqk-0004i1-Co@mlist.mta.ca> (raw)
In-Reply-To: <20161108100359.GB26241@mathematik.tu-darmstadt.de>

On 11/8/16 05:03, Thomas Streicher wrote:
> On Mon, Nov 07, 2016 at 04:03:18PM -0500, Eduardo Julio Dubuc wrote:
>> Hi, in this posting I will use the terminology used by most people in
>> the list.
>>
>> There are Grothendieck, Giraud and Elementary (Lawvere-Tierney) topos.
>>
>> Grothendieck are Giraud and Elementary, my question is:
>>
>> Are Elementary Giraud topos which are not Grothendieck ?
>
> But Grothendieck and Giraud toposes are the same. In the Elephant one
> can even find a relative Giraud Theorem.
>
> Thomas
>

By Giraud topos I mean all the assumptions in Giraud's theorem, exept a
small set of generators. What Grothendieck call "faux topos".

See SGA4 Exposse IV
Theoreme 1.2 (Giraud's theorem) and Example 2.8 (faux topos).

best  e.d.


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


       reply	other threads:[~2016-11-08 17:13 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20161108100359.GB26241@mathematik.tu-darmstadt.de>
2016-11-08 17:13 ` Eduardo Julio Dubuc [this message]
     [not found] <CACxkR4DXKO3sosJPB2YN+zGNGyKu7mnU-_Mfdi=GUXewek-w1Q@mail.gmail.com>
2016-11-08 17:20 ` Giraud_Elementary_? Eduardo Julio Dubuc
2016-11-09  9:13   ` Giraud_Elementary_? henry
2016-11-07 21:03 Giraud_Elementary_? Eduardo Julio Dubuc
2016-11-08 10:03 ` Giraud_Elementary_? Thomas Streicher

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