Discussion of Homotopy Type Theory and Univalent Foundations
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From: Richard Williamson <rwilli...@gmail.com>
To: Steve Awodey <awo...@cmu.edu>
Cc: Thierry Coquand <Thierry...@cse.gu.se>,
	Homotopy Theory <homotopyt...@googlegroups.com>
Subject: Re: [HoTT] Quillen model structure
Date: Thu, 14 Jun 2018 23:07:56 +0200	[thread overview]
Message-ID: <20180614210756.GC2094@richard.richard> (raw)
In-Reply-To: <20180614201503.GA1968@richard.richard>

> Exactly. It has been a little while since I was really working on
> this stuff, so I could be forgetting something, but as far as I
> know the test model structure on cartesian cubical sets is
> exactly the one coming from the theorem of Cisinski that Thierry
> cites using the obvious cylinder, and with empty S. Now, Thierry
> also says, I believe, that this model structure is the same as
> the one of Christian Sattler. How can this be?!

I was mis-remembering. If one looks at 8.4.34 - 8.4.38 in Les
préfaisceaux ..., one sees that S is taken (of course, now that I
think properly about it!) to be the (non-empty!) set of horn
inclusions.

In summary, the difference, from the point of view of Cisinski's
theory, between the type-theoretic model structure and the test
model structure seems to be precisely the choice of S.

Thank you to all!

  parent reply	other threads:[~2018-06-14 21:07 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-10 13:31 Thierry Coquand
     [not found] ` <CABLJ2vLi2ePKwf+Zha9Gx1jFgqJo9j2W0PsTctBZvf7F-xThHA@mail.gmail.com>
2018-06-11  8:46   ` [HoTT] " Thierry Coquand
2018-06-13 20:33 ` Michael Shulman
2018-06-13 20:50   ` Steve Awodey
2018-06-13 22:00     ` Michael Shulman
2018-06-14  9:28       ` Steve Awodey
2018-06-14  9:48         ` Bas Spitters
2018-06-14  9:58         ` Christian Sattler
2018-06-14 10:27           ` Steve Awodey
2018-06-14 13:44             ` Steve Awodey
2018-06-14 14:52               ` Christian Sattler
2018-06-14 15:42                 ` Steve Awodey
2018-06-14 15:47               ` Michael Shulman
2018-06-14 16:01                 ` Steve Awodey
2018-06-14 18:39 ` Richard Williamson
2018-06-14 19:14   ` Steve Awodey
2018-06-14 20:15     ` Richard Williamson
2018-06-14 20:32       ` Ulrik Buchholtz
2018-06-14 21:07       ` Richard Williamson [this message]
2018-06-14 19:16   ` Thierry Coquand
2018-06-14 19:35   ` [HoTT] Quillen model structure, PS Thierry Coquand

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