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From: Michael Barr <barr@math.mcgill.ca>
To: Categories list <categories@mta.ca>
Subject: "injective" terminology
Date: Tue, 18 May 2010 09:38:35 -0400 (EDT)	[thread overview]
Message-ID: <E1OEVlf-0007BM-2m@mailserv.mta.ca> (raw)

Since there has been such a lively discussion of language (which I have
kept out of because I have seen too many papers start out by saying, "By
ring, we mean a commutative ring with unit"), I though I would bring up
one that has long bothered me. There are too many contexts in which you
have a concrete category (say of compact hausdorff spaces) in which you
are dealing with both injective objects and 1-1 maps that I feel we need a
better word for the latter than "injective".  Of course, I could just
revert to 1-1 and perhaps I will.  But we have "projective" and
"surjective" for the dual.  This suggests "superjective", except that
that is so ugly.

Any thoughts?

Michael

P.S. I originally used *-autonomous to mean symmetric and then I wrote a
paper called, "Non-symmetric *-autonomous categories", so I am just as
guilty.


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             reply	other threads:[~2010-05-18 13:38 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-05-18 13:38 Michael Barr [this message]
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
     [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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