From: Steve Vickers <s.j.vickers@cs.bham.ac.uk>
To: peklund@cs.umu.se
Cc: categories@mta.ca
Subject: Re: How can we have a categorical definition of "theory"
Date: Fri, 10 Nov 2017 17:28:04 +0000 [thread overview]
Message-ID: <E1eDK2e-0000f2-SB@mlist.mta.ca> (raw)
In-Reply-To: <508ad670e2ff1525f0596b3c79485c04@cs.umu.se>
Dear Patrik,
It's absolutely vital to Grothendieck's idea of toposes as generalized
spaces. It's essentially categorical logic that allows you to think of
toposes as spaces and geometric morphisms as continuous maps.
For an introduction, see my TACL talks
http://www.cs.bham.ac.uk/~sjv/talks.php
particularly numbers 1-4 (the Olomouc tutorials).
Steve.
On 10/11/2017 16:49, peklund@cs.umu.se wrote:
> ...
>
> Categorical "logic" in a topos to me makes no practical sense at all.
>
> Patrik
>
>
[For admin and other information see: http://www.mta.ca/~cat-dist/ ]
next prev parent reply other threads:[~2017-11-10 17:28 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-07 1:13 Some questions about different notions " Mike Stay
2017-11-07 23:57 ` ptj
2017-11-09 7:13 ` How can we have a categorical definition " Patrik Eklund
2017-11-10 13:33 ` Steve Vickers
2017-11-09 11:26 ` Some questions about different notions " Andrée Ehresmann
2017-11-10 0:04 ` Michael Shulman
[not found] ` <Prayer.1.3.5.1711072357070.4648@carrot.maths.cam.ac.uk>
2017-11-09 16:03 ` Mike Stay
2017-11-10 0:00 ` ptj
[not found] ` <5A05AAB4.5020000@cs.bham.ac.uk>
2017-11-10 16:49 ` How can we have a categorical definition " Patrik Eklund
[not found] ` <508ad670e2ff1525f0596b3c79485c04@cs.umu.se>
2017-11-10 17:28 ` Steve Vickers [this message]
2017-11-10 4:56 Patrik Eklund
2017-11-11 1:25 David Yetter
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