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From: Dmitry Roytenberg <starrgazerr@gmail.com>
To: Categories list <categories@mta.ca>
Subject: Re: when does preservation of monos imply left exactness?
Date: Wed, 26 Oct 2011 13:59:33 +0200	[thread overview]
Message-ID: <E1RJ3NV-00060I-F3@mlist.mta.ca> (raw)

I'll try again...

On Mon, Oct 24, 2011 at 11:23 AM, Dmitry Roytenberg
<starrgazerr@gmail.com> wrote:
> Dear category theorists,
>
> It is well known that any functor that preserves finite limits
> preserves monomorphisms, and that for an additive right-exact functor
> between abelian categories, the converse is also true. Is it known how
> far this extends to the non-additive setting? In other words, what
> exactness properties of two categories and a functor between them
> would suffice to conclude that the functor preserves finite limits if
> and only if it preserves monos? For instance, is it enough to assume
> that the categories be Barr-exact and that the functor preserve all
> colimits, finite products and monos to conclude that it also preserves
> equalizers?
>
> Any references would be extremely helpful.
>
> Thanks,
> Dmitry
>


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             reply	other threads:[~2011-10-26 11:59 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-26 11:59 Dmitry Roytenberg [this message]
2011-10-26 21:52 ` Richard Garner
2011-10-27 10:32 ` George Janelidze
2011-10-27 22:08   ` Steve Lack
2011-10-28 12:27   ` Dmitry Roytenberg
2011-10-28 21:36     ` George Janelidze
2011-10-29  6:01       ` Correcting a misprint in my previous message George Janelidze
     [not found] ` <C86754D7A15D4A118F901BAD51AA3331@ACERi3>
2011-10-29 21:55   ` when does preservation of monos imply left exactness? Dmitry Roytenberg
     [not found]   ` <CAAHD2LKCe2kg=t7=FzkOmzHesZoQWX_itcAgjTRVh6SrL31tSA@mail.gmail.com>
2011-10-29 23:10     ` George Janelidze
2011-10-31 10:45       ` Dmitry Roytenberg

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