From: David Roberts <droberts@maths.adelaide.edu.au>
To: "categories@mta.ca" <categories@mta.ca>
Subject: Re: are fibrations evil?
Date: Fri, 17 Sep 2010 11:47:06 +0930 [thread overview]
Message-ID: <E1OwmB5-0000wX-LK@mlist.mta.ca> (raw)
Mike wrote:
>If one defined the identity types and pullbacks using limits in Gpd in the
>kosher 2-categorical sense, then it seems to me that one should be
>able to define an equivalent model using arbitrary functors between
>groupoids to represent the dependent types, rather than merely the
>fibrations.
This seems (to me) to be analogous to extending one's notion of
covering space to allow for empty fibres - indeed, the
characterisation of covering spaces as representations of Pi_1 needs
this.
David
PS +1 for using 'kosher' :)
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next reply other threads:[~2010-09-17 2:17 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-17 2:17 David Roberts [this message]
-- strict thread matches above, loose matches on Subject: below --
2010-09-24 23:43 Fred E.J. Linton
2010-09-17 4:36 John Baez
2010-09-18 13:50 ` Joyal, André
2010-09-19 14:57 ` David Yetter
[not found] ` <F8DA87C6-CBED-44AE-B964-B766A95D8417@math.ksu.edu>
2010-09-19 18:21 ` Joyal, André
2010-09-20 17:04 ` Eduardo J. Dubuc
2010-09-20 16:59 ` Eduardo J. Dubuc
2010-09-22 2:52 ` Toby Bartels
[not found] ` <20100922025245.GA14958@ugcs.caltech.edu>
2010-09-22 18:56 ` Eduardo J. Dubuc
[not found] ` <4C9A5156.3010307@dm.uba.ar>
2010-09-22 21:06 ` Toby Bartels
2010-09-15 11:43 Thomas Streicher
2010-09-16 0:28 ` Michael Shulman
2010-09-16 1:14 ` Peter LeFanu Lumsdaine
[not found] ` <AANLkTinosTZ2NQW9biPxiwpX9zPi5m=kwvA16nHjK=Xu@mail.gmail.com>
2010-09-16 9:47 ` Thomas Streicher
2010-09-16 10:00 ` Prof. Peter Johnstone
[not found] ` <alpine.LRH.2.00.1009161023190.12162@siskin.dpmms.cam.ac.uk>
2010-09-16 10:46 ` Thomas Streicher
2010-09-17 7:44 ` Toby Bartels
[not found] ` <20100916094755.GA19976@mathematik.tu-darmstadt.de>
2010-09-17 5:01 ` Michael Shulman
2010-09-18 13:48 ` Thomas Streicher
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