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This is an old revision of this page, as edited by Pretzels (talk | contribs) at 13:18, 5 March 2015 (→‎A cup of tea for you!: new WikiLove message). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

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Dear Takuya Murata,

thanks for your edits of the Wikipedia entry "Urs Schreiber"!

I was wondering if you might have some energy left to edit. There is a Wikipedia page for the "nLab". As you probably know, this is a wiki for research mathematics which I had once created (on November 28, 2008). Maybe it would make good sense to link to that from the page with my name?

Also, if people wonder about book publications, maybe this here would help to point to?

In any case, many thanks for your time. With best regards, Urs Schreiber (talk) 15:55, 22 March 2014 (UTC)[reply]

Hello,
It's cool to be contacted by the actual subject of the article. I've added a link to nLab, and started a publication list section, which should establish the "notability" (inclusion criterion in wikipedia), using a link you provided.
Thank you for the suggestion!
-- Taku (talk) 13:46, 23 March 2014 (UTC)[reply]
Thanks!
Thanks that you found the time to do this. I know that you have better things to do. Let me know if I might ever return the favor in some way.
Urs Schreiber (talk) 16:28, 29 March 2014 (UTC)[reply]
(Since you asked). There has been a speculation as to your nationality, something wikipedia editors care about :) It would thus help if you tell about your nationality somewhere, say, in your website. -- Taku (talk) 17:50, 31 March 2014 (UTC)[reply]

Greetings

Hi Taku: I'm hoping to ask you for some feedback on an ad-hoc chart I'm drawing. Don't worry, it's not for Wikipedia. I just need someone who is well versed in commutative rings! If you find the time, take a look at this googledoc pdf. I have charts like this which are even more extensive for noncommutative rings, but these nice commutative conditions like Gorenstein and Cohen-Macaulay did not fit well there, so I'm doing a more dedicated chart.

I'm sure I've left out implications and/or things that are worth including. Whatever suggestions you can make about additions or omissions, I'd be interested in hearing. One thing I'm curious about is if regular rings are Gorenstein. The only information I found was that regular local rings are Gorenstein. Another thing I wonder about is if you can connect Cohen-Macaulay downward to other conditions on the chart. I just have no feeling for these types of rings. Please also browse that family of domains over on the left. That is also a new addition. Thanks: Rschwieb (talk) 01:38, 2 April 2014 (UTC)[reply]

Extended content
Hello. Here are some quick suggestions for addition: integrally closed domain, Zariski ring, analytically unramified ring, excellent ring, pseudo-geometric ring, Jacobson ring, complete local ring, rings with cohomological conditions (e.g., Tor-dimension), catenary ring, Henselian ring, Krull ring. (cf. Glossary of commutative algebra.) Structurally speaking, it might make sense to separate local rings from non-local ones: my view is that the local ring theory has a distinctly different flavor from the global theory (not surprising since they correspond to the local and global situations in algebraic geometry. Maybe I will write you more later. -- Taku (talk) 23:27, 3 April 2014 (UTC)[reply]
Thanks, that's a start. You made me realize I'd garbled things concerning normal rings and integrally closed domains. I'll also add Jacobson ring.
I had been hesitant to add Krull, Zariski, Henselian, excellent rings since I'm not sure how they connect with the existing nodes. I would be instantly convinced, however, if you take any one of those conditions and are able to attach two implications to other nodes (of course an "other node" may be another missing node you're adding.)
I'll add a "local only" version of my charts to my to-do list, but for my application now I think I need to keep them in one chart.
I was really hoping for some help with connections between existing rings! Can you draw any more errors at the moment? For instance, I've since noticed that I could draw an arrow from local Cohen-Macaulay to Noetherian. Is Noetherianness a local property, so that I can actually draw it from "Cohen-Macaulay" to Noetherian instead? (Please excuse these gaps in my knowledge.)
I should be able to update the chart today or tomorrow. Thanks for taking a shot, and I hope you keep looking at it. Rschwieb (talk) 19:35, 4 April 2014 (UTC)[reply]
So as I reread this, it looks like a normal domain is the same thing as an integrally closed domain. Is that accurate, to your knowledge? Rschwieb (talk) 13:15, 5 April 2014 (UTC)[reply]
ah, so you really want to see more arrows? To be honest, I'm not sure if that's really useful. (I'm still looking forward to seeing an update.) For example, I can imagine many arrows coming to a noetherian ring or integral domains, just because many rings are assumed to be noetherian rings or domains to begin with. (ditto for local ring). As for "Noetherianness a local property", no, it's not. There is an example of Nagata. (cf. Localization (algebra), the article I didn't finish; maybe we should merge it to somewhere.) Finally, yes, a normal domain is the same as an integrally closed domain. A normal ring is slightly more general (since it need not be a domain.) So, you can add normal domain -> normal ring. -- Taku (talk) 13:20, 5 April 2014 (UTC)[reply]
You're not the first person to cast doubt on the usefulness of such a chart (but you are only the second. Everyone else loves these things! ) Initially I was worried about complexity as well, but I wound up being surprised at how well things turned out. You just can't go crazy with nodes. This is one reason that I didn't include some of the rings you mentioned. But that said, they are good candidates for an independent chart.
Take a look at the previous commutative ring chart I kept. This chart was developed from a noncommutative one by merging nodes that become the same in the commutative case, and adding arrows that appear if you assume commutativity. Things like UFD and Cohen-Macaulay weren't on the noncommutative chart so that's why they aren't on this one. This chart is actually being developed for a different purpose, so it does have some awkward spots.
The first chart I shared here will probably have some nodes removed. For example, "Noetherian domain" is something I just put in for convenience early on, and it's not really a useful node. By the way, is it not true that I can add an arrow between regular and Gorenstein? Rschwieb (talk) 16:30, 5 April 2014 (UTC)[reply]
For the last question, yes, "regular local" implies "Gorenstein local" (proof: finite projective dim implies vanishing of sufficiently high Ext. see Gorenstein ring). Since regular and Gorenstein are both local properties by definition, this means regular -> Gorenstein. As for the chart, I beg to differ on excluding some rings; for example, Henselian ring is a very important ring in commutative ring theory; if it's missing, I get the impression the chart is incomplete. -- Taku (talk) 11:51, 7 April 2014 (UTC)[reply]
Great, thank you! I'm open to being convinced about Henselian rings (or any type, for that matter.) The only thing I can tell from Henselian ring is field-->local Henselian-->Henselian-->semilocal. Is it possible that Henselian rings are semiperfect or maybe dual? Is there a relationship with the Cohen-Macaulay cluster? Rschwieb (talk) 13:19, 7 April 2014 (UTC)[reply]
So you're saying, basically, "Henselian" is boring, as far as the chart-making is concerned? But isn't it the whole point of the ring theory making implications simple (read dull)? This is why, for example, if I were making the chart, I separate the global theory from the local theory; i.e., simplification. In other words, if the theory requires a chart to be expalined, it's not a good theory. (But keep in mind: I personally don't like ring inclusions chain at, say, the end of the lead of [iIntegrally closed domain]]; so I have a different preference than others.) Anyway, we have: complete Noetherian local ring -> Henselian. Not sure any other. -- Taku (talk) 13:31, 7 April 2014 (UTC)[reply]

Er... there is definitely some sort of misunderstanding here because those first two sentences are incredibly bizarre. I was getting excited because I found a solid thread of connections which definitely makes Henselian rings fit well, and then I started to ask if those connections could be tightened. I am hardly qualified to know if Henselian rings are interesting or not: that's why I'm asking you! I hope this clarifies things.

if the theory requires a chart to be expalined, it's not a good theory. Whatever, man :P This isn't meant to explain, and the theory certainly doesn't require it, so I think you're barking up the wrong tree. Maps of hierarchies are objectively useful for developing long-term memory and comprehension. This is very much like an entity-relationship model which is a key tool in relational databases.

It's fine if you have ideas about how such a chart should look, but remember I'm haven't asked for suggestions on that scale. I'm looking for nodes and edges. The goals and applications I'm headed towards would be best met by charts like these examples. I'm still interested in continuing because you've been very helpful already, and let me know if you're not interested in helping anymore, but please try not to be a back-seat driver  :) Rschwieb (talk) 17:06, 7 April 2014 (UTC)[reply]

Oh and let me also add that I'm taking notes to make a local version of the chart, but I just don't want to get sidetracked too far on that task since this one is more pressing. Rschwieb (talk) 17:16, 7 April 2014 (UTC)[reply]
(Sorry about the early post; I was feeling very tired. Let's try again) to answer your question (Henselian), I don't really know a non-local situation. I remember Bourbaki had an exercise that is related to a characterization of Henselian ring. (But I don't know the exact statement.) Finally, Henselian isn't related to regularity. (A suggestion for an addition: étale algebra, complete intersection ring.) For the importance of this notion, see for example the lede of http://stacks.math.columbia.edu/download/smoothing.pdf. It discusses the approximation property. I wonder how do you handle a conjecture? -- Taku (talk) 11:31, 8 April 2014 (UTC)[reply]

Sorry for the long silence! For the past month some more pressing business took up most of my time. I've been returning to this task lately. I'm trying to untangle something about the local definitions of Dedekind domains and Prufer domains:

For a domain D:

  • D is Dedekind iff all localizations at maximal ideals are DVRs
  • D is Prufer iff all localizations at maximal ideals are VRs.

According to what I've read, it looks like some definitions of Dedekind, Prufer and valuation domains preclude the ring from being a field. Definitions with exclusions are not very aesthetically pleasing, but I suppose there are good reasons for it. Usually exceptions like this are made to streamline statements of equivalent characterizations, so I'm hoping that there's really no harm in thinking of fields as special cases: I just expect that this viewpoint might make equivalences more awkward to state. Is there some more serious reason one might not want fields to be Dedekind domains, other than this matter of convenience? Rschwieb (talk) 15:01, 4 May 2014 (UTC)[reply]

I don't really know of a serous reason to exclude a field from being a Dedekind domain. Our Dedekind domain does include a field as a Dedekind domain. If you take a view that a Dedekind domain corresponds to an (affine) algebraic curve (not necessarily over a field), then maybe you want to require it to have dim 1; not a field. But a field is a PID in all the definitions I know, so I personally don't take this viewpoint. If you think a Dedekind domain is precisely a hereditary integral domain, then, again, a field should be a Dedekind domain. As for a non-domain Dedekind domain?, I'm not sure is it the same as a hereditary commutative ring? -- Taku (talk) 21:38, 4 May 2014 (UTC)[reply]
Ah, ok! I'm glad it is not a rigid thing in commutative algebra. Exclusive definitions are certainly aesthetically unpleasing. I do indeed prefer the definition of "commutative hereditary domain." I've been taking a long look at the list of rings above that I didn't incorporate yet. The excellent-catenary-G-J2-Nagata-geometrically regular cluster looks very cohesive and makes a good chart, although I have no idea how it connects to the other things (except "Noetherian"). I haven't placed Zariski or Henselian rings yet. I've started a local chart too, and that needs a lot of work. I'll have to remember to push them out soon for feedback. Rschwieb (talk) 15:04, 16 May 2014 (UTC)[reply]
It just occurred to me "dimension theory" might be a reason you want to exclude a zero-dimensional ring (since a Hilbert polynomial will have negative degree.) "Geometrically," curves and points are fundamentally different after all. Anyway and by the way, are you interested in creating a chart for Nagata ring and such for Wikipedia? I found this stuff very confusing and I and some other readers can definitely use such a chart to make sense of a big picture. -- Taku (talk) 00:14, 17 May 2014 (UTC)[reply]
Here are some updated charts for you to look at. I'm not sure I could make a chart small or pretty enough for use on those pages, but I would be perfectly willing to make one if the right subgraph was worked out.
Commutative rings: https://drive.google.com/file/d/0BycNM32IN1JBb1FVbGtvSmkwLXM/edit?usp=sharing
Local rings: https://drive.google.com/file/d/0BycNM32IN1JBcG1iaUxCUkRPY2c/edit?usp=sharing
The cluster I haven't included yet: https://drive.google.com/file/d/0BycNM32IN1JBMUNXelVIUEhuc1k/edit?usp=sharing Rschwieb (talk) 18:06, 27 May 2014 (UTC)[reply]
Wondering if you overlooked this update or not! In the meantime, I've added complete intersection rings between regular local and local Gorenstein. Rschwieb (talk) 20:13, 2 June 2014 (UTC)[reply]

Speedy deletion nomination of Goop (newsletter)

Hello TakuyaMurata,

I wanted to let you know that I just tagged Goop (newsletter) for deletion, because the article doesn't clearly say why the subject is important enough to be included in an encyclopedia.

If you feel that the article shouldn't be deleted and want more time to work on it, you can contest this deletion, but please don't remove the speedy deletion tag from the top.

You can leave a note on my talk page if you have questions. Ging287 (talk) 00:14, 5 April 2014 (UTC)[reply]

Nomination of Law of Economy of Characters for deletion

A discussion is taking place as to whether the article Law of Economy of Characters is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.

The article will be discussed at Wikipedia:Articles for deletion/Law of Economy of Characters until a consensus is reached, and anyone is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.

Users may edit the article during the discussion, including to improve the article to address concerns raised in the discussion. However, do not remove the article-for-deletion notice from the top of the article. Brainy J ~~ (talk) 17:07, 10 April 2014 (UTC)[reply]

Notice

Notice WMF's usual non-answer answer.

Actually, I think that the thing for you to notice in that thread is that "the WMF" hasn't answered at all. Every person speaking in that thread is speaking purely as fellow volunteers—some to notice that the development of math software is controlled by volunteers; others complain that, despite being good at math, they still can't understand most math articles; still others to suggest ways and means of improving the situation. But there is no reply from "the WMF" anywhere in that discussion. WhatamIdoing (talk) 22:15, 5 May 2014 (UTC)[reply]

I did notice that the comment in that thread was from User:WhatamIdoing rather than User:Whatamidoing (WMF). But I didn't notice any comment in the thread to the effect that "the development of math software is controlled by volunteers". Who said that? Deltahedron (talk) 17:31, 6 May 2014 (UTC)[reply]
You did: "that currently WMF allocates essentially no resources to this and it continues entirely on volunteer effort". WhatamIdoing (talk) 19:34, 6 May 2014 (UTC)[reply]
I nowhere stated that volunteers control mathematical software development: indeed I specifically wrote that volunteer effort is less effective through not being integrated into WMF development. This is a reference to the complaint made here for example. Deltahedron (talk) 19:53, 6 May 2014 (UTC)[reply]
The volunteers are the ones doing the work, and therefore they are controlling the work. The WMF does not and (in practice) cannot control WP:VOLUNTEERs. WhatamIdoing (talk) 20:37, 6 May 2014 (UTC)[reply]
Not what I said, not what I meant and not correct (see the diff). Deltahedron (talk) 21:01, 6 May 2014 (UTC)[reply]

Ok, maybe it should have been "non-answer non-answer". I also missed the distinction between WhatamIdoing and WhatamIdoing (WMF). In any case, my point still stands: Deltahedron asked a rather pointed question about the math rendering issue and got no-answer. We should continue the discussion at Jimbo's talk but I would say for the record Deltahedron's inquire "represents" to a large extent the voice of the math editor community if I understand correctly (certainly mine.) -- Taku (talk) 20:28, 6 May 2014 (UTC)[reply]

Or perhaps even more accurately: "There has been no official answer yet, despite this thread being open for an entire day and a half already". WhatamIdoing (talk) 20:37, 6 May 2014 (UTC)[reply]
Or even more accurately still: Jimbo Wales has answered with an interesting challenge which I have relayed to WT:WPM. Deltahedron (talk) 20:56, 6 May 2014 (UTC)[reply]

Example in article on Finitely generated modules

Hi, I recently posted a question about an example in the article on Finitely generated modules. I think you originally contributed this example (along with a ton of great additions to the article overall!), so I thought you might be able to clarify my confusion. Thanks! Tesseran (talk) 18:09, 13 June 2014 (UTC)[reply]

The article Narabunka Women's College has been proposed for deletion because of the following concern:

Does not comply with notability guidelines for schools.

While all constructive contributions to Wikipedia are appreciated, content or articles may be deleted for any of several reasons.

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Narabunka College

You're right. I must have confused it with college in another language, a primary school. Regards. --Why should I have a User Name? (talk) 11:21, 14 June 2014 (UTC)[reply]

Fine tuning

I look forward to hearing your reasoning here. Deltahedron (talk) 20:02, 20 June 2014 (UTC)[reply]

Thanks

for your prompt response on Central polynomial and Posner's theorem! Deltahedron (talk) 06:31, 28 June 2014 (UTC)[reply]

July 2014

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Re:Formatting Improvements

The page in question was improved by my edits. So please be more specific about your criticism. — Preceding unsigned comment added by 99.241.166.168 (talk) 01:39, 15 July 2014 (UTC)[reply]

I was thinking of the format change in the articles like Divisor (algebraic geometry). -- Taku (talk) 20:21, 15 July 2014 (UTC)[reply]

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A tag has been placed on Alisa Matviychuk requesting that it be speedily deleted from Wikipedia. This has been done under section A7 of the criteria for speedy deletion, because the article appears to be about a person or group of people, but it does not indicate how or why the subject is important or significant: that is, why an article about that subject should be included in an encyclopedia. Under the criteria for speedy deletion, such articles may be deleted at any time. Please read more about what is generally accepted as notable.

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Mark project defunct?

TakuyaMurata, I see that you have been a contributor to WikiProject Citizendium Porting. I am inclined to mark it as defunct, as there has been no work on it in a couple of years and it seems unlikely that Citizendium will be a useful source of content for Wikipedia articles in the future. Is that o.k. with you? RockMagnetist (talk) 18:00, 28 July 2014 (UTC)[reply]

I can totally understand. It's ok; it served its purpose by now. -- Taku (talk) 20:11, 30 July 2014 (UTC)[reply]

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Edit discussion.

Hello User:Takuya, Thanks for your many edits at the Wikipedia page. There is a BRD which I am trying to start at the Wikipedia page which someone is trying to oddly remove from the Talk page. Could you take a look at this when/if time allows? LawrencePrincipe (talk) 15:03, 30 July 2014 (UTC)[reply]

Krull dimension zero

In section Examples of Krull dimension, you have added an item about dimension zero. It is the fourth item about this dimension. IMO, the items deserve to be sorted for regrouping those related to dimension zero. Maybe, a section devoted to dimension zero could be useful. Also there is another property of dimension, that is yet lacking: "A finitely generated commutative algebra over a field has Krull dimension zero if and only if it is a finite dimensional vector space (over the same field). D.Lazard (talk) 08:49, 11 August 2014 (UTC)[reply]

Too be clear, I didn't add anything new. I made a minor formatting so that the item was not buried. Anyway, I do agree on the regrouping. We should also spell out zero-dim means possibly zero prime ideals are maximal and consequently for example Jacobson radical and nilradical are the same. I'm having a trouble with a non-Noetherian case, since a zero-dimensional Noetherian ring is just an Artinian ring and the article on the topic lists several equivalent characterization. -- Taku (talk) 11:36, 11 August 2014 (UTC)[reply]

You've removed the tag More Footnotes tag from the article Noncommutative projective geometry without adding any footnotes. Since the article has zero footnotes for the statements you've made in the article, why did you remove the More Footnotes tag? Thanks! Stesmo (talk) 17:30, 11 August 2014 (UTC)[reply]

I removed the tag because it didn't make much sense. Not every article needs footnotes. If you were to add a cleanup tag and if the reason for doing isn't obvious, it is necessary to explain say in the talkpage to explain why the tag is needed. -- Taku (talk) 23:50, 11 August 2014 (UTC)[reply]

Nomination of Ken Nimori for deletion

A discussion is taking place as to whether the article Ken Nimori is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.

The article will be discussed at Wikipedia:Articles for deletion/Ken Nimori until a consensus is reached, and anyone is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.

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Meaning of gr in Hausdorff completion

Hello, I was wondering if you could add what the notation means as it appears at Hausdorff completion. This is not covered by Filtration (mathematics), nor as a generalization in profinite group. ᛭ LokiClock (talk) 10:55, 4 September 2014 (UTC)[reply]

Done. -- Taku (talk) 11:25, 21 September 2014 (UTC)[reply]

Proposed deletion of Toyama College of Welfare Science

The article Toyama College of Welfare Science has been proposed for deletion because of the following concern:

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WikiProject Military history coordinator election

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Limits and colimits of rings

In your recent edit of Ring (mathematics), one of the limits has its arrow pointing from right to left. Did you intend it this way? — Anita5192 (talk) 00:42, 5 December 2014 (UTC)[reply]

You mean a part about "projective limit"? Then the direction of the arrow below "limit" is correct (I think). -- Taku (talk) 01:56, 5 December 2014 (UTC)[reply]
Okay. Thanks! — Anita5192 (talk) 02:20, 5 December 2014 (UTC)[reply]

Nominations for the Military history Wikiproject's Historian and Newcomer of the Year Awards are now open!

The Military history Wikiproject has opened nominations for the Military historian of the year and Military history newcomer of the year. Nominations will be accepted until 13 December at 23:59 GMT, with voting to begin at 0:00 GMT 14 December. The voting will conclude on 21 December. MediaWiki message delivery (talk) 08:41, 7 December 2014 (UTC)[reply]

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Speedy deletion nomination of Kelley Rae O’Donnell

Hello TakuyaMurata,

I wanted to let you know that I just tagged Kelley Rae O’Donnell for deletion, because the article doesn't clearly say why the subject is important enough to be included in an encyclopedia.

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Proposed deletion of Dylan Scott Pierce

The article Dylan Scott Pierce has been proposed for deletion because of the following concern:

Unsourced BLP

While all constructive contributions to Wikipedia are appreciated, content or articles may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the {{proposed deletion/dated}} notice, but please explain why in your edit summary or on the article's talk page.

Please consider improving the article to address the issues raised. Removing {{proposed deletion/dated}} will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. JBH (talk) 23:31, 7 February 2015 (UTC)[reply]

Nomination of Dylan Scott Pierce for deletion

A discussion is taking place as to whether the article Dylan Scott Pierce is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.

The article will be discussed at Wikipedia:Articles for deletion/Dylan Scott Pierce until a consensus is reached, and anyone is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.

Users may edit the article during the discussion, including to improve the article to address concerns raised in the discussion. However, do not remove the article-for-deletion notice from the top of the article. JBH (talk) 15:47, 8 February 2015 (UTC)[reply]

Just double-checking

Recently I've been working with minimal primes in commutative rings, and online resources send some mixed signals. I figure you probably know the answer offhand.

For example, I see it proven that the zero divisors of a reduced Noetherian ring are the union of minimal primes here, and it's also commented that the converse is true "in Noetherian rings." On the other hand, this link and this link contend that the Noetherian hypothesis is superfluous in both cases. In the past I've learned that the CommAlg wiki is not really the best resource, and I feel like the mathOverflow solutions I linked to are quality. Aren't the propositions (the ones that don't assume Noetherianity) standard commutative algebra fare?

Finally, there is another result I'm interested in: when do the minimal primes in reduced rings have nonzero annihilators? Again, I have read that this is true for Noetherian rings, but my experience above makes me cautious. Let me know what you think: thanks! Rschwieb (talk) 14:25, 10 February 2015 (UTC)[reply]

On the top of my head, this topic is usually discussed in the context of associated primes. So that's why "Noetherian" is a standard and natural assumption. I don't know about the non-noetherian case. One possibility is that a ring need to have at most finitely many minimal prime ideals (for the union of minimal prime ideals to equal the set of zerodivisors.) Maybe the fastest way is to just work out the proof yourself. -- Taku (talk) 15:43, 10 February 2015 (UTC)[reply]
In fact, you actually don't need any assumption. Here is a proof: Let R be a reduced ring, D set of zerodivisors and all the (possibly zero) minimal prime ideals.
Let x be in D. Then xy = 0 for some nonzero y. Since R is reduced, (0) is the intersection of all and thus y is not in some . Since xy is in all ; in particular, in , x is in .
(stolen from Kaplansky, commutative rings, Theorem 84). We drop the subscript i. Let . S is multiplicatively closed and so we can consider the localization . Let be the pre-image of a maximal ideal. Then is contained in both D and and by minimality . (This direction is also immediate if R is Noetherian by the theory of associated primes.)
Personally, I'm a bit surprised that you don't need "Noetherian". Good to know!. -- Taku (talk) 18:27, 10 February 2015 (UTC)[reply]

Great: thanks for taking a look. Rschwieb (talk) 17:58, 13 February 2015 (UTC)[reply]

Proposed deletion of Atomi Junior College

The article Atomi Junior College has been proposed for deletion because of the following concern:

Junior schools are not notable...

While all constructive contributions to Wikipedia are appreciated, content or articles may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the {{proposed deletion/dated}} notice, but please explain why in your edit summary or on the article's talk page.

Please consider improving the article to address the issues raised. Removing {{proposed deletion/dated}} will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. JMHamo (talk) 15:38, 2 March 2015 (UTC)[reply]

Interested in ring examples?

I'd like to ask if you'd be interested in contributing to a site I've set up for ring theory!

First take a look at how it works: Database of Ring Theory.

I can set up an admin account for you to contribute materials. There are a lot of gaps that could be filled in for the commutative subset.

The site looks pretty stark, but I'm gradually making improvements to it. Either way, I hope you get a chance to look at it. Rschwieb (talk) 01:18, 4 March 2015 (UTC)[reply]

Nomination of Atomi Junior College for deletion

A discussion is taking place as to whether the article Atomi Junior College is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.

The article will be discussed at Wikipedia:Articles for deletion/Atomi Junior College until a consensus is reached, and anyone is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.

Users may edit the article during the discussion, including to improve the article to address concerns raised in the discussion. However, do not remove the article-for-deletion notice from the top of the article. JMHamo (talk) 15:15, 4 March 2015 (UTC)[reply]

A cup of tea for you!

Saw your discussion on Talk:Main Page – nice try! — Pretzels 13:18, 5 March 2015 (UTC)[reply]