From: Toby Bartels <toby@ugcs.caltech.edu>
To: Timothy Porter <t.porter@bangor.ac.uk>
Subject: Re: "injective" terminology
Date: Sat, 22 May 2010 10:08:25 -0700 [thread overview]
Message-ID: <E1OGAyD-0001Wf-AS@mailserv.mta.ca> (raw)
In-Reply-To: <4BF7FCB1.70303@bangor.ac.uk>
Timothy Porter wrote:
>I always thought that ind-object in the work of Grothendieck and the SGA
>seminars was short for inductive object.
The "ind-" in "ind-object" does stand for "inductive",
which is dual to "projective" for the "pro-" in "pro-object",
but an ind-object is not the same thing as an injective object
(and also a pro-object is not the same thing as a projective object).
http://ncatlab.org/nlab/show/ind-object
http://ncatlab.org/nlab/show/injective+object
http://ncatlab.org/nlab/show/pro-object
http://ncatlab.org/nlab/show/projective+object
--Toby
[For admin and other information see: http://www.mta.ca/~cat-dist/ ]
next prev parent reply other threads:[~2010-05-22 17:08 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-05-18 13:38 Michael Barr
2010-05-19 9:27 ` Prof. Peter Johnstone
[not found] ` <alpine.LRH.2.00.1005191017510.6866@siskin.dpmms.cam.ac.uk>
2010-05-19 9:59 ` Michael Barr
2010-05-20 22:04 ` George Janelidze
2010-05-21 16:35 ` Toby Bartels
2010-05-22 15:48 ` Timothy Porter
[not found] ` <4BF7FCB1.70303@bangor.ac.uk>
2010-05-22 17:08 ` Toby Bartels [this message]
[not found] ` <004b01caf868$759d49d0$0b00000a@C3>
2010-05-20 22:27 ` Michael Barr
2010-05-19 7:44 Fred E.J. Linton
2010-05-22 20:50 Fred E.J. Linton
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