Wikipedia:Featured article removal candidates/Quantum mechanics

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[edit] Quantum mechanics

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The article has a very short lead, completely inadequate for a FA its size (3a). I've raised the issue at the talk page but it has not been addressed. It should be removed untill it attains FA quality again. Loom91 07:01, 12 May 2006 (UTC)

It's also factualy inaccurate, speculative and contradictory. I give the following passages as examples:-

"This probability cloud obeys a quantum mechanical principle called Heisenberg's Uncertainty Principle, which states that there is an uncertainty in the classical position of any subatomic particle, including the electron; so instead of describing where an electron or other particle is, the entire range of possible values is used, describing a probability distribution. So in normal atoms with electrons in stationary states, the probability of the electron being within the nucleus (or somewhere else in atom within similarly small volume) is nearly zero according to the Uncertainty Principle (it is nearly zero as the nucleus has a volume and is not a point). Therefore, quantum mechanics, translated to Newton's equally deterministic description, leads to a probabilistic description of nature."

It's not only subatomic particles that obey uncertainty principle, this is a false claim. It is also a false claim that the probability cloud obeys the uncertainty principle. The probability cloud obeys the Shroedinger equation. Uncertainty principle only predicts the existence of such a probability cloud.

Comment - I am a PhD student in a subject closely related to quantum mechanics. It is not wrong to say that the probability cloud obeys the uncertainty principle (UP). Indeed the UP is a constraint on the spread of the probability distribution *in phase space*, be it defined as the Wigner function or any other sensible way. However I agree with your other criticisms. I reworked this paragraph. -Cedric

The sentence "Therefore, quantum mechanics, translated to Newton's equally deterministic description, leads to a probabilistic description of nature." is devoid of any remote semblance of meaning.

"In some cases, both general relativity and quantum mechanics converge. As an example, general relativity is unable to explain what will happen if a subatomic particle hits the singularity of a black hole which is a phenomenon predicted by general relativity and involves gravity in the macro world. Only quantum mechanics can provide the answer: the particle's position will have an uncertainty that follows the Heisenberg Uncertainty Principle, such that it might not really reach the singularity and thus escape the possible collapse to infinite density."

This passageis contradictory, inaccurate, unreferenced speculation. Such shortcomings are far too numerous for me to list all of them. Suffice to say the article needs a major copyediting by experts to meet the ever-increasing FA standards. Loom91 07:16, 12 May 2006 (UTC)

Comment - I'm no physicist - in fact, I haven't taken a science class in almost five years - so I can't speak to your allegations about the accuracy of this article. However, we luckily have an expert on hand (you) who seems to know a fair bit about the subject of quantum mechanics. Seeing as you've already spotted a few seemingly big problems, why not be bold and fix them? Since this isn't technically a valid objection (as it wasn't listed on the talk page prior to nomination), that might be a good idea. To speak to your only valid objection, the too-short lead (which you mentioned on the talk page on May 9), yes, it is true that WP:WIAFA requires a lead of 2-3 paragraphs. However, for me, this violation is too minor to merit demotion, as it is easily fixed by somebody who has thoroughly read the article and has a good understanding of the topic. (Again, for lack of any other knowledgable and interested volunteers that I know of, I'll nominate you.) Cheers! The Disco King 17:30, 12 May 2006 (UTC)

Comment. Unfortunately my knowledge of the subject is not comprehensive enough to actually correct all those errors, while I can recognise them as errors. {{sofixit}} is always the best solution to any problem, but not always feasible (in this case because I don't have enough time). Loom91 07:58, 15 May 2006 (UTC)

• Comment

1. I'm happy with the lead. Criterion 3a requires just "a concise lead section that summarizes the entire topic and prepares the reader for the higher level of detail in the subsequent section". I note, too, that some reviewers in the FAC room have been getting themselves into a knot about the number of paragraphs that a lead should comprise. IMV, that is too strict: there are a number of ways of writing a satisfactory lead, and some of them may not require precise numbers of paragraphs. That is why 3a deliberately avoids the issue.

2. Since the complaint, as aired on the talk page, is not, IMV, actionable, a question hangs over whether this is a valid nomination. It would be proper to withdraw the nomination and go through the process again, citing better reasons. Give the contributors a chance to fix it before the nomination.

3. I agree with Disco that it would be an excellent outcome if Loom91 corrected what s/he has identified as factual errors. This is the very thing that WP's science articles need. But reviewers and nominators are, of course, under no obligation to do so.

4. There are a few problems in the article: the caption for Figure 1 is ... whoaaa ... far too long, and I hate the italics. Figure 2 is just a question mark: why bother? The prose is OK, but could do with a run through to fix awkward little things such as "which we today call Quantum Mechanics".

It would be sad to defrock this one. If the nominator agrees to fix the factual errors, I'll agree to copy-edit it. Tony 02:04, 16 May 2006 (UTC)

• As I said before, I would love to correct the errors but my expertise does not allow me to. In any case, "correcting factual errors" is not the solution here, sourcing statements is. Wikipedia is not in the buissness of determining "facts", it is in the buissness of practicing WP:NPOV, and it is impossible for me to not only know what the correct stement would be but also source it from presumably papers in technical journals. This a job for a real expert, and as long as none is forthcoming, I think it will be best to give this article a temporary leave from the hectic life of a FA. Loom91 07:35, 16 May 2006 (UTC)

• A while back, I nixed the paragraph about "both general relativity and quantum mechanics converge", which was beyond redemption, and I just made a few other fixes. If I weren't on deadline in my real job-type job, I could do more. As it stands, I advocate removal, just because quantum mechanics demands (and deserves) a solid article, and this isn't it. Anville 20:13, 28 May 2006 (UTC)