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Timeline for Criteria for coherence of rings

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Sep 30, 2013 at 9:46 answer added Fred Rohrer timeline score: 2
Jul 25, 2013 at 18:04 comment added Manny Reyes @MartinBrandenburg, I am very late to this conversation, but I think you meant to say that it's precisely the condition that the finitely presented modules form an abelian category.
Apr 30, 2011 at 18:59 answer added Hagen timeline score: 4
Jan 15, 2011 at 21:20 answer added Emerton timeline score: 8
Jan 15, 2011 at 20:58 comment added Donu Arapura Yes, right. I think the idea of coherence of sheaves goes back to the work of Cartan and Oka in several complex variables.
Jan 15, 2011 at 20:52 answer added user12235 timeline score: 5
Jan 15, 2011 at 20:40 history edited Mariano Suárez-Álvarez CC BY-SA 2.5
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Jan 15, 2011 at 17:03 comment added Mariano Suárez-Álvarez My guess is that the idea must have preexisted FAC in the analytic case. Cartan, maybe? (Although that's pretty much like saying «in Euler»...!)
Jan 15, 2011 at 13:50 comment added Donu Arapura Also, see Serre "Faisceaux Algebriques Coherent", Annals 1955, page 210 for a definition of coherence for a sheaf of commutative rings.
Jan 15, 2011 at 9:14 comment added Kevin Buzzard +1 Martin! Coherence is introduced very early on in EGA in this context (so presumably Grothendieck knew about the notion in the early 60s). Somehow one reason it's less widely-known is, I guess, that when Hartshorne wrote his book he stuck to the Noetherian case for simplicity, so just defined a coherent sheaf of modules as one which locally looked like a f.g. module, so one doesn't see the subtlety of the definition in the non-Noeth case. Course this is all in the commutative case, but EGA is a place to look [look in index for "coherent"...]
Jan 15, 2011 at 8:45 comment added Martin Brandenburg 1+. I don't think that coherence is just a technical condition. It's the best condition for that the category of finitely generated modules is abelian. Due to laziness, we often restrict to noetherian rings for this.
Jan 15, 2011 at 6:02 history asked Mariano Suárez-Álvarez CC BY-SA 2.5