From: Robin Houston <robin.houston@gmail.com>
To: Michael Barr <barr@math.mcgill.ca>
Cc: Categories list <categories@mta.ca>
Subject: Re: Name for not-quite-additive categories
Date: Sat, 7 Jan 2012 08:02:12 +0000 [thread overview]
Message-ID: <E1RjX1E-000768-LO@mlist.mta.ca> (raw)
In-Reply-To: <E1RjIsQ-0003jJ-O7@mlist.mta.ca>
The term semiadditive has been used for at least 45 years[1], and is still in use today[2]. It's not used all that often, but it has a good pedigree and is unambiguous.
Robin
1. Barry Mitchell, Theory of Categories, 1965, section 1.18
2. http://ncatlab.org/nlab/show/biproduct#semiadditive_categories_11
On 6 Jan 2012, at 19:04, Michael Barr <barr@math.mcgill.ca> wrote:
> Has anyone settled on a term to describe categories (such as commutative
> monoids) in which finite sums and products coincide but are not quite
> additive? I guess they are commutative monoid enriched.
>
> Michael
>
> --
> Any society that would give up a little liberty to gain a little
> security will deserve neither and lose both.
>
> Benjamin Franklin
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next prev parent reply other threads:[~2012-01-07 8:02 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-06 19:04 Michael Barr
2012-01-07 2:02 ` George Janelidze
2012-01-07 8:02 ` Robin Houston [this message]
2012-01-07 8:04 ` rlk
2012-01-07 11:29 ` Prof. Peter Johnstone
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