Re: Grothendieck: more complete URL

[Steve Vickers <s.j.vickers@cs.bham.ac.uk>]

Dear Colin,

Can I ask a technical question about foundations here?

Does the "enough injectives" result assume a classical base theory? The
classical result for module categories uses choice, and my understanding
is that the result for sheaf categories uses Barr covers to make
available the classical result.

I wonder if there's an unequivocally constructive formulation.

Regards,

Steve.

Colin McLarty wrote:
> AG intended this paper to hit the very center of homological algebra:
> from now on homological algebra is about derived functors on Abelian
> categories with enough injectives -- and he justifies this by proving
> (against the general expectation) that all sheaf categories have
> enough injectives .   Of course there are other resolutions besides
> injective, we will use them too, but they are special cases for
> special purposes.


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