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History of tag 0315

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type time link
changed the proof 2021-07-18 70471ab
Fix error in proof in modules on sites

Thanks to Owen
https://stacks.math.columbia.edu/tag/093M#comment-6266
changed the proof 2014-09-20 e802cd2
Comment about Tag 0315

In the proof of Tag 0315 the ideal I need not need to be nilpotent.
Instead we use that I/I^n is nilpotent in the ring R/I^n. Your
proof is essentially how the proof of Nakayama's lemma in the
nilpotent case works.

I have added a sentence with the explanation.

The reason for not adding your argument is that generally speaking
we try to avoid having the same thing proven in multiple locations,
although in this case your argument is so short that in some sense
it might be quicker to put it in.

On Tue, Sep 16, 2014 at 3:51 PM, Minseon Shin <shinms@berkeley.edu> wrote:
> Hello,
>
> Here is a comment regarding the beginning of the proof of Lemma 10.91.1 (Tag
> 0315). I think the reference to Nakayama's lemma (Lemma 10.18.1, Tag 00DV)
> is sort of confusing here because, unless I am mistaken, it seems to me that
> the claim "M/IM \to N/IN surjective implies M/I^{n}M \to N/I^{n}N surjective
> for all n \ge 1" is true even if M and N are not finitely generated and I is
> not nilpotent. Here is my claimed proof (which is by induction on n):
>
> It is equivalent to say "\phi(M)+IN = N implies \phi(M)+I^{n}N = N for all n
> \ge 1". Suppose \phi(M)+I^{n}N = N. Then I\phi(M)+I^{n+1}N = IN. Adding
> \phi(M) to both sides gives \phi(M)+I^{n+1}N = \phi(M)+(I\phi(M)+I^{n+1}N) =
> \phi(M)+IN = N.
>
> Best,
> Minseon
changed the statement and the proof 2010-10-06 3b0820b
Fixing references, etc

	Fallout from moving stuff in the previous commit.
changed the proof 2010-08-31 2e1c8ce
Constructible subsets of Noetherian spaces

	Namely, the characterization in terms of intersections with
	irreducible closed subsets.
changed the proof 2009-09-29 efc115c
Algebra+Homology: Change to avoid forward references

	modified:   algebra.tex
	modified:   homology.tex
assigned tag 0315 2009-08-21 15d48db
Added new tags

	modified:   tags/tags
changed the label to lemma-completion-generalities 2009-08-17 946301b
More on comlpetion and towards Nagata rings are universally Japanese

	modified:   algebra.tex
changed the statement and the proof 2009-08-17 946301b
More on comlpetion and towards Nagata rings are universally Japanese

	modified:   algebra.tex
created statement with label lemma-ses-completion in algebra.tex 2009-08-17 54b3586
More stuff in algebra.tex:

	Integral closure is transitive
	Surjectivity of completion of surjective maps?
	Definition of I-adically complete modules
	Criterion as to when completion is complete
	Completion complete in Noetherian case
	Finiteness criterion (still not done)
	Residue field extension of map dvrs bounded
	Complete local ring with finitely generated maximal ideal is
		Noetherian
	Lemmas on Japanese property
	Starting to prove Tate's theorem on Japaneseness of complete
		rings

	modified:   algebra.tex