Wikipedia:Featured article candidates/Quark/archive2

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The following is an archived discussion of a featured article nomination. Please do not modify it. Subsequent comments should be made on the article's talk page or in Wikipedia talk:Featured article candidates. No further edits should be made to this page.

The article was not promoted by User:SandyGeorgia 00:50, 7 October 2008 [1].

Quark[edit]

Nominator(s): —Anonymous DissidentTalk
previous FAC

Over the past week or so, I have completely re-written this article. Before, it didn't make too much coherent sense and was quite covered in redundancy. I believe the article now meets the criterion. I think the text is comprehensive and provides an all-round view of the topic. The article is sourced to forty-three (43) reliable references, consisting of a healthy meld of web and book sources. It is well formatted and of a good length (36KB), and the text is brightened up by six (6) illustrative images. It has a strong lead section that I believe introduces the article concisely but informatively. I hope reviewers will provide me constructive criticism and express their thoughts on the article. —Anonymous Dissident<span <style="font-family:Verdana;color:Gray">Talk 02:01, 25 September 2008 (UTC)[reply]

Oppose 1a - I don't know much about physics (imagine; a mathematics aficionado not know much about physics!) and so I can't comment on much of the technical side of this article, but the prose isn't up to par.

  • The very first sentence I object to. Two successful restrictive clauses begin with "that", which reads extremely awkwardly, and "is placed under the classification of fermion" is simply redundant.
  • "The quark forms one of the two basic constituents of matter" - as above, unnecessarily verbose. "The quark is" would do just fine. Additionally, two sentences in a paragraph - two consecutive sentences, and the only two sentences - both begin with "The quark", when "it" would do just as well.
  • "are in abundant existence" - also unnecessarily verbose.
  • "are assigned various other properties"
  • "..., and never in isolation" - "and" is unnecessary here, and disrupts the flow of the prose. Furthermore, the sentence that contains this phrase is long, winding, and confusing.

I'm out of time for now; I've read a fair portion of the article though have only taken points from the very beginning. I intend to finish the reading and point out more examples tomorrow. Nousernamesleft (talk) 02:59, 25 September 2008 (UTC)[reply]

    • All repaired. I hope you'll reconsider your opposition; these particular problems are very minor. —Anonymous DissidentTalk 03:34, 25 September 2008 (UTC)[reply]
      • I agree they're minor, but many minor errors throughout just two paragraphs isn't a good indication - much of the article is like that. I'll give the promised further examples soon. Nousernamesleft (talk) 20:34, 25 September 2008 (UTC)[reply]
        • I note that Brianboulton has remarked on the prose below, and is currently copyediting, so I'll hold off comments, and might help a bit. Nousernamesleft (talk) 23:55, 25 September 2008 (UTC)[reply]
        • I don't understand the following sentence: "The two proposed the theory in attempt to explain the numerous hadrons and new particles that were being found at the time, and were dubbed the point-like constituents of the baryon and meson." Nousernamesleft (talk) 23:57, 25 September 2008 (UTC)[reply]
          • To be honest, I'm not sure how to simplify that. Basically, hadrons were being found at the time, and much uncertainty surrounded whether they had constituents or whether they were fundamental particles. Yheir properties indicated they could be split, and quarks were brought into play to take the place of those constituents. —Anonymous DissidentTalk
  • It's been changed satisfactorily. A brief rereading of the article allows me to strike my oppose, though I probably shouldn't give a support until tomorrow, when I can have a proper read. Nousernamesleft (talk) 02:18, 28 September 2008 (UTC)[reply]

comment - Looks pretty good after a quick read. In places the text is a bit thick, and leans jargony (especially towards the end sections). There may not be a good way to reduce that without very long explainitory sections, which can be equally awful to read. --Rocksanddirt (talk) 04:44, 25 September 2008 (UTC)[reply]

I tried to make the science easy to understand. If you could point me towards the things that you thought were overly complex, I'll see what I can do. In regards to the thick text, I assume you refer to the last text section? I agree that could be split, but I'd be unsure of a section header scheme there. —Anonymous DissidentTalk 05:28, 25 September 2008 (UTC)[reply]
The fancy external link checker observed that two of the external links had an issue that I didn't understand (so I didn't try to fix). --Rocksanddirt (talk) 04:47, 25 September 2008 (UTC)[reply]
Which ones? All of them worked for me. —Anonymous DissidentTalk 05:28, 25 September 2008 (UTC)[reply]

Comments

Issues resolved, Ealdgyth - Talk 15:43, 1 October 2008 (UTC)[reply]
Otherwise sources look good, links checked out with the link checker tool. Ealdgyth - Talk 13:29, 25 September 2008 (UTC)[reply]
All publisher citations overturned and replaced. —Anonymous DissidentTalk 13:58, 26 September 2008 (UTC)[reply]

Comments, mainly on the proseSupport I meant to come back earlier, and say that this looks good, has been worked on meticulously and is ready for FA. Brianboulton (talk) 23:36, 3 October 2008 (UTC)[reply]

  • Lead
    • An untested theory, or one which is supported by little evidence should, I suggest, be termed a hypothesis.
      • I would disagree with that. A hypothesis is notational of the expected results of a particular question or experiment. A theory denotes a broad intellectual architecture which answers many important questions about natural phenomena. There may be cause to believe that this theory doesn't answer those questions correctly (or more probably, that the burden of proof has not been met). But the quark is proposed as a fundamental particle. Currently the article calls it a theory in all but one location, and uses "hypothesis" once. I suggest that the word "hypothesis" there (2nd sentence of the last paragraph of the intro) be changed to "thesis." Huadpe (talk) 06:42, 27 September 2008 (UTC)[reply]
        • But, in 1964, the burden of proof had not been met — read the second paragraph of the history section. While now it is a theory, calling it a theory in that sentence is anachronistic, as would calling Slovakia a "country" in a sentence about something which happened before Czechoslovakia splitted. -- A r m y 1 9 8 7 ! ! !  11:05, 27 September 2008 (UTC)[reply]
  • History
    • "At the time of the theory’s initial proposal, the physical particle "zoo", as it is sometimes referred to, consisted of the two types of hadron (the meson and the baryon) and several of the first leptons, among many others" (my emphasis) For the life of me I can’t work out what his means, specially the "among many others".
      • With respect, that's not a prose issue. What part are you not understanding? The particle physics model consisted of many different types of hadron, as well as a few early leptopns, among various other particles like the atom that had been known of for decades. —Anonymous DissidentTalk 06:33, 26 September 2008 (UTC)[reply]
        • Initially, I couldn't understand the phrase "among many others" - what did "others" refer to? You have explained this above - "others" means various particles like the atom. But, in your explanation, you say the model consisted of "many different types of hadron", while in your original sentence you say it consisted of the two types of hadron (the meson and the baryon). So I'm still confused. Brianboulton (talk) 14:56, 26 September 2008 (UTC)[reply]
          • Sorry for my lack of clarity here. There are two essential types of hadron: meson and baryon. The meson has one quark and one antiquark, while the baryon contains three quarks. All quarks possess a spectrum of different properties such as electrical charge etc.. From quark-antiquark and quark-quark-quark combinations, as well as the property combinations that occur therein, we are given a wide range of different mesons and baryon forms; about 200, to be precise. —Anonymous DissidentTalk 15:44, 26 September 2008 (UTC)[reply]
    • This construction: "to temporarily help explain" – splits the infinitive.
      —This is part of a comment by Brianboulton (of 16:49, 25 September 2008 (UTC)), which was interrupted by the following: [reply]
      So what? -- A r m y 1 9 8 7 ! ! !  19:11, 25 September 2008 (UTC)[reply]
      • Splitting this infinitive leads to a very awkward construction, because the verb "help explain" is complex. The situation is easily avoided by "could be utilized temporarily, to explain..."etc
    • Also the sentence containing it is extremely long and winding.
    • Prolix: "It was in the same year that..." Suggest should be "Also in 1964, extensions…..." etc (we need reminding what year we’re in)
    • Inappropriate use of mdash as hyphen
    • "added appendage"? "added”" is redundant
    • Prolix: "...since no hadrons that had been observed at that time seemed to indicate the presence of another quark type". Try: "...since no hadrons yet observed indicated the presence..." etc.
    • "This number grew..." "This" isn't anchored to anything. You need to say "The number of possible quark types grew..."
    • You don’t need "nine years later" when you give the year 1973. Thus: "In 1973 the number of possible quark types grew to six, when Makoto..." etc
    • Awkward phrasing: "...six quarks made more sense than four considering the two’s study of CP-violation in the same year". Try: "...six quark types made more sense than four on the basis of their current studies of CP-violation".

Look, I’m only half way through the History section and I’m finding prose problems just about every sentence. This article should have had a proper copyedit before coming to FAC, but if you like, I’ll do one now. It might take a while, but it’ll be worth it, as no way is this prose going to make FA as it stands. By the way, I’m a non-scientist but I find the subject interesting, even if I don’t understand all the detail. Leave me a note on my talkpage if you want me to do a copyedit. Brianboulton (talk) 16:49, 25 September 2008 (UTC)[reply]

  • I have done a general copyedit, removing redundancies, repetitions, verbose phrasing etc. I am reluctant to do more for fear of disturbing the physics. It would be as well if someone checked my edits to see that I haven't inadvertently altered a meaning. Anyway, I believe the prose flows better now than it did, notwithstanding my limited ability to understand the article. I hope this has helped. Brianboulton (talk) 15:13, 26 September 2008 (UTC)[reply]
    • I'll have a full read-through of the article later to see whether you inadvertently removed any terminologies in your copyediting. In general, however, I'd like to say that I appreciate your work in improving the article's prose. Best, —Anonymous DissidentTalk 15:47, 26 September 2008 (UTC)[reply]
  • Oppose I have addressed the most obvious issues, but the article still hav lots of room for improvement. -- A r m y 1 9 8 7 ! ! !  19:11, 25 September 2008 (UTC)[reply]
Could you point out where? I can't improve if you don't specify. Where can it be iomproved? Prose? I agree there are some concerns. Article completeness? I assure you I've written about pretty much everything relevant to quarks. —Anonymous DissidentTalk 22:19, 25 September 2008 (UTC)[reply]
I've placed inline tags in some relevant parts — for example, in the Spin section a sentence seems to suggest that quarks rotate around their own axis (something point-like particles can't do) and in the table there is an unsourced coupling between the sign of spin and flavors which I had never heard of before. And the prose is cumbersome, even if I'm trying to fix it when I can.
As for completeness, I don't think there is much more that could be said. (Unless we merge the articles about individual flavors into this one, as I proposed on the talk page.) -- A r m y 1 9 8 7 ! ! !  23:13, 25 September 2008 (UTC)[reply]
I've repaired both those instances. You were right about the point-like particles there, thanks for pointing it out. Turns out spin is an intrinsic property. The unsourced part was also wrong; I dunno how I got that different quarks have an integral + or - spin. they can all have both. Fixed. Thanks for pointing those details out. —Anonymous DissidentTalk 06:28, 26 September 2008 (UTC)[reply]

Comments from Giggy

  • This is looking much better then when I last looked at it. Which is good; exams are soon.
  • "The six flavors of quarks and their most likely decay modes. Mass increases moving from left to right." - opening an article with this will scare the reader off. You need wikilinks, at least, if not a much more simple explanation.
    • Oh, and up and down are inline... so do they have the same mass?
      • Replaced with a more suitable image. It shows the Standard Model, which is quite relevant at the lead. —Anonymous DissidentTalk 12:50, 26 September 2008 (UTC)[reply]
  • "which participates in strong interaction" - participate isn't the right verb here, I don't think. I just checked my textbook (I know) and it doesn't specifically state that they interact via the strong force (it talks about colour force but not in the same context). I've heard it explained as "they interact via the strong nuclear (force|interaction)", force being more common, but that might not be "correct". I dunno if this helps at all, and perhaps participate is the right verb... I just doubt it.
  • are two varieties of hadron, distinguished by the number of quarks in the hadron" - just end the sentence at "quarks".
  • "The proton and neutron hadrons are the constituents of the atom, the most basic form an element can take" - probably put this sentence before the previous one

From the lead. Sorry about the ramblings. Giggy (talk) 10:08, 26 September 2008 (UTC)[reply]

I've replaced "participate" with "interact", even if now it sounds so repetititititive... -- A r m y 1 9 8 7 ! ! !  10:49, 26 September 2008 (UTC)[reply]

Comment: I withdraw my opposition. Meanwhile, I'm going to read the article and the featured article criteria more carefully, to decide whether to vote for support. -- A r m y 1 9 8 7 ! ! !  13:22, 26 September 2008 (UTC)[reply]

  • Anonymous Dissident, please read the WP:FAC instructions and remove the "done" templates. (This FAC is quickly becoming unreadable between the graphics and the sigs.) SandyGeorgia (Talk) 21:43, 26 September 2008 (UTC)[reply]
  • As for me, I support, as I can't see any serious issue with the article anymore, but I've requested a peer review, because I'm not an expert in quantum chromodynamics, and I propose that the factual accuracy of the more technical sections of the article be double-checked before the article is featured. -- A r m y 1 9 8 7 ! ! !  15:50, 28 September 2008 (UTC)[reply]
    • I have asked Army to close the peer review he has opened; in the spirit of the guidelines, a FAC and peer review should not be active at the same time. —Anonymous DissidentTalk 03:28, 29 September 2008 (UTC)[reply]
  • Comment. Looks generally good, but needs some review from someone familiar with the subject; I've found some small misunderstandings so far. Fortunately, I'm familiar with the subject, and in the process of taking a look. -- SCZenz (talk) 13:59, 29 September 2008 (UTC)[reply]
    • Can you provide some examples of the said misunderstandings? I'd be curious to know to what you refer, being the writer of the article; if there are some concepts I'm not grasping, I'd be most grateful to be corrected for my own intellectual purposes, as well as for the benefit of the article. —Anonymous DissidentTalk 14:58, 29 September 2008 (UTC)[reply]
      • There are two misunderstandings so far, both in one sentence: "The discovery of the top quark was the most significant of any of the six quarks, because it was found to be hundreds of times bigger than the hadrons it was theorized to occupy." The first issue is the use of the word "bigger," by which I assume you (or whoever wrote the sentence) meant "more massive," but they're hardly the same thing in this case. The second issue is that the top quark was more massive than "the hadrons it was theorized to occupy." Nobody ever claimed that specific hadrons contained top quarks; they expected the top quark to appear in new hadrons, and to be discovered by the observation of those new hadrons. However, once it was realized that the top quark was very heavy, the Standard Model also predicted that the top quark would appear outside of hadrons. The point was, whoever wrote the sentence roughly understood the issues I've described, but seemed at least to have the explanation a bit muddled. If I see other points of confusion, I'll edit them, as indeed I already did in this case. -- SCZenz (talk) 15:39, 29 September 2008 (UTC)[reply]
  • Comment. The history section currently details the predictions of each kind of quark before it describes any as being discovered. It also leaves out any hint at why new quarks were proposed. These two issues together make it seem like a bunch of quarks were just made up and turned out to be there. In fact, the theoretical predictions of new quarks followed experimental results that gave strong support to the original set, and sought to address specific problems with the existing theory. -- SCZenz (talk) 15:58, 29 September 2008 (UTC)[reply]
    • I'm not sure if I wrote that; if I did, I'm sorry, it must have been a slip of the mind: I remember learning the difference between something being "big" and "massive" years ago. ;) In regards to them being parts of hadrons, I was sure I removed that earlier on today. The history section: please, if you have information regarding why the quarks were proposed, add it with sources. I mentioned CP-violation as being the catalyst for the six-model, but found it difficult to find information on why the others were proposed. Your improvements are appreciated. —Anonymous DissidentTalk 16:15, 29 September 2008 (UTC)[reply]
      • I have rewritten and reordered parts of the history, and it looks better to me now. Comments appreciated! -- SCZenz (talk) 20:41, 29 September 2008 (UTC)[reply]
        • Looks good. There was something you did that wasn't in chronological order, so I've fixed that, but, otherwise, a fine job. —Anonymous DissidentTalk 02:00, 30 September 2008 (UTC)[reply]
  • Comments: First this is a preliminary review, I'm giving this after a quick read (article) and without reading the other comments so I'm not influenced by them. I'll give a more detailed review later.Headbomb {ταλκ – WP Physics: PotW} 20:09, 29 September 2008 (UTC)[reply]
  1. Is this article up to date with the 2008 Particle Review?Headbomb {ταλκ – WP Physics: PotW} 20:09, 29 September 2008 (UTC)[reply]
    I would imagine so. I haven't compared this article directly to that, but my sources are, many of them, very recent and up-to-date. Most of what is known about quarks has been established for quite some time, anyway. —Anonymous DissidentTalk 02:04, 30 September 2008 (UTC)[reply]
  2. Why is quark table in various colors? What's the color scheme?Headbomb {ταλκ – WP Physics: PotW} 20:09, 29 September 2008 (UTC)[reply]
    The quarks match the antiquarks, as do their symbols. The generations are differentiated by different colors. The electric charge is differed for each half of the pair in every gen. —Anonymous DissidentTalk 02:04, 30 September 2008 (UTC)[reply]

Continuing my (Giggy's) comments, there's a few more up above.

  • "At the time of the theory's initial proposal, the physical particle "zoo", as it is sometimes referred to" - sometimes referred? I dunno, if the term was used by the majority it'd be different, but as is I'd just go with something that doesn't seem slang-ish.
    • Displaced, although there is an article... ;) —Anonymous DissidentTalk 13:52, 30 September 2008 (UTC)[reply]
      • Looks like someone re-added it. I think it's slightly more than slang; we have an article on it. I think it is probably the best term to describe the spectrum of physical particles. Linked it to the article in case of misunderstanding. Do you have any true objection to its usage? —Anonymous DissidentTalk 03:47, 1 October 2008 (UTC)[reply]
  • "such as electrical charge and spin" - I'd give the links again here for those that skip the lead.
  • "extensions to the Gell-Mann–Zweig model were proposed, when another duo of physicists" - if they extensions were proposed because of Glashow and Bjorken's work, then remove the comma (and the comma after their names)
  • "The word was originally coined by Murray Gell-Mann as the sound ducks make." - what, he coined the word, and then he wasn't sure about it, and then he found it in someone else's book? Not clear.
  • I'm not a big fan of the massive blockquote in the Etymology section, if it can be avoided (it probably can).
  • "by a process known as weak interaction" - wordiness... just use "by the weak interaction"
  • "A quark can decay into a lighter quark by emitting a W boson" - yet bosons are bigger than protons (which are made of quarks)... how does it emitt something that big?
    • Big is not to heavy. Such is particle physics. Why is the top quark so heavy, heavier even than a clump of hadrons in a gold nucleus? We don't know yet. I'll still contact Army or SCZenz to see if they can clarify better than I can. —Anonymous DissidentTalk 02:12, 1 October 2008 (UTC)[reply]
  • Shouldn't you be using the funky template for the quark symbols in the Weak interaction section? (for uud/udd)
  • I don't see what the introduction to atoms and ions in the Electric charge section has to do with quarks ("The total electric charge of a nucleus..." onwards)
    • Because a quark's electrical charge is the governing factor in the charge of protons and neutrons, and the number of protons vs. electrons is what determines an atom's electric charge, or lack thereof, and that is what makes an atom an atom or an ion an ion. —Anonymous DissidentTalk 03:45, 1 October 2008 (UTC)[reply]
  • Could Image:Quark structure proton.svg be changed so the ups are the same colour? (see below)

I'll finish it off... soon. :-) Giggy (talk) 10:37, 30 September 2008 (UTC)[reply]

For information, Glashow and Bjorken were the ones who did the extending, so that's the direction the wording should be clarified in. Also, there is a very good reason why the ups are a different color -- see the section on color charge in the article! -- SCZenz (talk) 10:43, 30 September 2008 (UTC)[reply]
Yep, my mistake on the colours - I added that comment before reading that section, and didn't go back and erase it afterwards. Struck now. Giggy (talk) 10:48, 30 September 2008 (UTC)[reply]
  • Support as all addressed. Giggy (talk) 13:16, 1 October 2008 (UTC)[reply]
  • SupportComments. I am inclined to support, but there are a few problems that should be fixed:
Issues resolved, Ruslik (talk) 16:18, 1 October 2008 (UTC)[reply]
1) Lead:
a) "usually known as flavors"—usually is redundent here;
b) "charm, strange, top, and bottom flavors are highly unstable"—remove highly, it is vague;
c) "and differ from quarks only in that some of their properties are inverse"—I suggest "and differ from quarks only in that all their charges have opposite sign".
d) "In nature, quarks are always found bound together"—drop 'found', it is unnecessry.
e) "mesons consist of two quarks, and baryons consit of three"—I suggest "mesons consist of one quark and one anti-quark, and baryons consit of three quarks"
2) History:
a) ""zoo", as it is sometimes referred to, consisted of many types of hadrons, and several of the first leptons, among many others."—I do not understand, which 'many others' refers to. I suggest ""zoo", as it is sometimes referred to, consisted of several leptons and hundreds of different hadrons."
b) "These partons were later recognized as up and down quarks."—needs a citation. As I understand partons are not necessary constituant quarks. They can be quarks from the "sea", i.e. quark-antiquark pairs that spontaniously appear and annihilate. In addition some partons are gluons (see [2]).
c) It should be mentiond that J/ψ meson is also known as charmonium.
3) Properties:
a) "but is an arbitrarily named property that takes its name"—the word name is used twice in one sentence.
b) "The six flavors are named up, down, charm, strange, top and bottom"—drop the word "named".
c) In the same sentence I see "the top and bottom flavors are also sometimes known as truth and beauty, "—please, drop "sometimes".
d) In the next sentence there are two "very" words. Remove them, because they are "very" redundent".
e) "Quarks of higher generations have greater masses and thus are less stable than quarks of lower generations."—not necesary true. For instance, B_mesons are more stable than D_mesons.
f) When discussing generations it should be mentioned that leptons are also divided into the same three generations. This is not a property of the quarks only.
g) "but the electric charge and other quantum numbers are the additive inverse of that of quarks." Please, use simpler language. For instance, "but the electric charge and other other charges have the opposite sign".
h) "There are numerous hadrons, all of which result from the variety of possible quark combinations that can occur and all of which are differentiated by the properties their quarks confer upon them."—this statement is only partially true, because some of the hadrons are excited states of others, and they can have exactly the same quark content.
i) "Electric charge is a property intrinsic to the quark mechanism, and is an important factor in the overall hadron model."—remove this sentence. It provides no usuful inforamation.
j) The same with the following sentence "The electric charge of quarks is an important factor in the construction of atoms."
k) "Composed of duu"—change to "composed of one d and two u quarks".
l) Not only gluons contribute to the mass of hadrons—quarks-antiquarks pairs from the "sea" also contribute.
m) "the duu proton to the ddu neutron"—change to "the proton to the neutron".
n) "are the subjects of the quantum chromodynamics research field."—it is not clear what the word "field" means here. Is it a physical field or one of the areas of research?
o) "occurring approximately 1024 times every second."—unscientific statement. Please, remove it.
p) "that contributes to a quark's indivisibility."—Probably, hadron's indivisibility or quark's inseperability?
q) "The matrix of interactions and exchanges that occurs in a hadron model is complicated by the fact that gluons are able to engage in a process of self-exchange; that is, gluons are able to emit gluons and exchange them with other gluons."—putting it simpler "The strong interactions are non-linear, becauses gluons can emit gluons and exchange gluons with other gluons.

Ruslik (talk) 19:15, 30 September 2008 (UTC)[reply]

I think that's everything. there were a few things I specifically didn't fix, only two or three. For instance, the thing about antiparticles and "opposite sign": that's not scientific enough, in my opinion. "Inverse" isn't exactly a scientific word anyway, and it's more accurate than an "opposite sign". If there was anything else, just ask and I'll try and fix it/explain my change etc.. Thanks for a detailed review. —Anonymous DissidentTalk 04:47, 1 October 2008 (UTC)[reply]
I don't understand your argument about "opposite sign" at all. I don't think there's any imprecision introduced by that the term, which always means "additive inverse" as far as I know. When it costs us nothing in accuracy, using the simplest language possible is an easy choice. -- SCZenz (talk) 05:01, 1 October 2008 (UTC)[reply]
I changed to support, but can you comment about partons and their identification with up and down quarks (which is incomplete explanation in my opinion)? And also about about contribution of quark-antiquark pairs to the mass? Ruslik (talk) 05:18, 1 October 2008 (UTC)[reply]
I'll admit that I wasn't aware of the term "opposite sign" before, and thought it was a made up terminology. I'll change it now. In regards to the parton: my source says that the substructures that were implied to be within the quark by the 1968 SLAC tests were later identified as up and down quarks. Why this is a matter of debate I do not know; I would have thought it would have been obvious that the interior of the proton was composed of u and d? In regards to quark-antiquark pairs: I assume you mean the sea? Take a proton: three valence quarks, the field of gluons, plus the sea of q
q
. I am personally unsure of how much the sea realistically contributes to the mass, and I cannot find a source for it either. If either of you two have the knowledge/sources, I'd be hugely grateful. —Anonymous DissidentTalk 06:31, 1 October 2008 (UTC)[reply]
See this(p.9-10) for the discussion about partons and gluons-quarks. See also Parton_(particle_physics) article. The graph shows that additional q
q
 pairs (including s
s
 pairs) and gluons contribute to scattering, not only three valent quarks. You also can read this (pp.72-100). Latter I will provide additional sources. Ruslik (talk) 08:13, 1 October 2008 (UTC)[reply]
Yes, but the question posed concerned how much sea-quarks contribute to the mass of the hadron. —Anonymous DissidentTalk 08:49, 1 October 2008 (UTC)[reply]
In the case of up and down quarks, the valence quarks contribute very little to the mass of the hadron -- the quarks have a mass of a few MeV, while the hadron has a mass of at least 900 MeV! The extra energy is in the binding of the valence quarks, which is produced by the gluon field (of which "individual gluons" are quanta, but individual gluons are not a good approximation at low (i.e. ordinary) energy). Now, when you hit a sea quark when you do a deep inelastic scattering experiment, that sea quark is there (loosely speaking) because a gluon "split" into a quark and antiquark. Thus the sea quarks are a manifestation of the same phenomenon that gives the hadron the bulk of its mass, but it is very difficult to make a meaningful statement about "how much sea quarks contribute to the mass of the hadron." It will be difficult to find a source answering that question exactly, because on a technical level the question has no precise meaning. The conclusion, I think, is that our article should avoid such complexities! -- SCZenz (talk) 09:04, 1 October 2008 (UTC)[reply]
I'd agree; we are an encyclopedia, not a compendium of deep scientific analysis: this article provides more than cursory quark knowledge without presenting a book on the topic, which is quite fine in an encyclopedic context. I'm wondering: should we perhaps create a section on the matter of sea quarks? A mention on the distinction between valence and sea quarks, how they just form out of the vacuum? —Anonymous DissidentTalk 09:14, 1 October 2008 (UTC)[reply]
IMO, a section about sea quarks vs. valence quarks could be useful. Sea quark used to redirect to quark; I changed it to point to Parton (particle physics), but it could point to, e.g. Quark#Valence quarks and sea quarks if such a section were created. -- Army1987!!! 12:57, 1 October 2008 (UTC)[reply]
Would it have it's own header or would it come under something else, like properties? —Anonymous DissidentTalk 13:03, 1 October 2008 (UTC)[reply]
I would suggest a section called something like "quarks in hadrons," with three subsections:
  • Description of how quarks combine to make hadrons
  • Color confinement and gluons (already exists)
  • Sea quarks
SCZenz (talk) 15:06, 1 October 2008 (UTC)[reply]
Maybe an idea could be adding a section on sea quarks to Hadron, making Sea quark redirect to it, and adding a very short introduction to the concept of sea quarks and valence quarks to Quark, linking the more detailed explanation. -- Army1987!!! 11:12, 2 October 2008 (UTC)[reply]
  • Crucial Question How many domain experts have laid eyes on this article? I know exactly squat about the topic, of course, but from quick bouncing around related Wikipedia articles (no other research yet) I am leaning Oppose, probably per 1b. Ling.Nut (talk—WP:3IAR) 13:54, 2 October 2008 (UTC)[reply]
    Well, I've laid eyes on it. But I'm not done reading the whole thing yet, so I can't speak to whether the information is comprehensive. -- SCZenz (talk) 14:00, 2 October 2008 (UTC)[reply]
    I do not see any problem with 1b. The articles cover all major facts about quarks (except probably techniquarks?). Ruslik (talk) 14:12, 2 October 2008 (UTC)[reply]
Why, exactly, would you place opposition based on a hunch? —Anonymous DissidentTalk 14:48, 2 October 2008 (UTC)[reply]

(undent) You're rewording my statement. Not opposition, not a hunch. Leaning opposition, based on (possibly incorrect) perception that it omits facts )omitted unintentially because they are obvious ones... and for the reality that I read the article and still didn't have any idea what a quark was until I read other articles, which to my mind is unacceptable for an FA. But I have to close now, 'til tomorrow. Striking mention of Oppose to avoid miscommunication; will talk more tomorrow... Ling.Nut (talk—WP:3IAR) 16:05, 2 October 2008 (UTC)[reply]

Now, see here. Are you honestly telling me you read the whole article and have no clue what the subject matter is? It's stated quite clearly in the second statement, if the first was too jargony: "It is one of the two basic constituents of matter, the other being the lepton." —Anonymous DissidentTalk 16:12, 2 October 2008 (UTC)[reply]
Comment I'd like to see the content of this article unpacked a bit, especially in the lead. If you'd like to think of it as "Quarks for Dummies" feel free; I think of it as "Quarks for the People". :-) In my mind, it's an issue of accessibility to the broader public. However, it may be debatable whether "accessibility to the broader public" is a component of 1(a). I personally couldn't support without unpacking, but I'm not sure if it's a valid reason to oppose... perhaps I'll ask some other folks, and check back in later... Ling.Nut (talk—WP:3IAR) 07:22, 3 October 2008 (UTC)[reply]
Okay, thanks for your comment. I'm happy to alter the lead to this effect, but it will be pretty much impossible to "unpack" it when all I have to go on is that single word. Perhaps if you could provide examples of statements or concepts that you think require a more detailed explanation, then I could work on that. Otherwise, I'm somewhat fielding in the dark here. —Anonymous DissidentTalk 07:39, 3 October 2008 (UTC)[reply]
To Ling and AD: does this work for either of you? Giggy (talk) 07:43, 3 October 2008 (UTC)[reply]
Thanks for taking a stab, but quarks aren't substances. I'll try and think of something else. —Anonymous DissidentTalk 08:03, 3 October 2008 (UTC)[reply]

(undent) Hi again, I really don't mean to leave you hanging, but my Spousal Unit has many items on her Honey Do list today. I have copied the lead (temporarily) to User:Ling.Nut/page2 and will try to get to it this evening, which is probably late morning for those of you in the States. Ling.Nut (talk—WP:3IAR) 09:21, 3 October 2008 (UTC)[reply]


  • Comment My head exploded trying to comb through the article for problems so, can you at least integrate the "see also" section into the body of the text? Thanks. Ottava Rima (talk) 14:19, 3 October 2008 (UTC)[reply]
  • Please take a look at User:Ling.Nut/page2, and feel free to edit it mercilessly. I am not yet satisfied that it is finished, but I have to go to bed. I do think it is a great deal more perspicuous than the current lead of quark, though. Ling.Nut (talk—WP:3IAR) 17:25, 3 October 2008 (UTC)[reply]
  • I think it would be best for others with unexploded heads to do such. :) Quarks are best left to experts. :) Ottava Rima (talk) 18:52, 3 October 2008 (UTC)[reply]
  • Ling, I commend you for your work, but, in my honest opinion, I think it makes the lead more convoluted. Just my opinion. If the main problem is with the word "constituents", then it can be changed to "components". The first two sentences seem otherwise fine there, considering that links *are* provided. —Anonymous DissidentTalk 03:16, 4 October 2008 (UTC)[reply]

(undent) My point is that it's too condensed, to the point of opacity; no one can understand it without clicking through a number of other articles. Ling.Nut (talk—WP:3IAR) 03:23, 4 October 2008 (UTC)[reply]

Well, I'm sorry to tell you that such is particle physics. This article is about a concept in particle physics, an area that will always be quite complicated. This article is always going to require the reader to click on a few links if they want the background information; we would need an entire book to surmise all of the background information about particle physics. This article is comprehensive in its chosen topic, which is quarks. We aren't writing about particle physics; just one type of particle. See, for example, atom, another featured article. Very comprehensive about atoms, but doesn't shy away from using technicalities. —Anonymous DissidentTalk 04:55, 4 October 2008 (UTC)[reply]
  • Prose: it's only just OK. See my copy-editing of the lead for a demonstration of why the whole text could do with a polish. I'm surprised that "up- and down-quarks" are not hyphenated thus. Please watch out for the overuse of "being". Please ping me when it's better. Tony (talk) 05:15, 4 October 2008 (UTC)[reply]
    Up quark etc. aren't usually hyphenated. As for the overuse of being, my bad. I added most of them, but thanks to GrahamColm for fixing that. -- Army1987 ! ! ! 11:14, 4 October 2008 (UTC)[reply]

Support Oppose for now - the article has not reached the required standard yet. At this late stage I should not be finding mistakes, (see article history), but, my major concern is that possibilities to make the article more accessible have not been fully explored. Take just one example —hadronisation; the word appears without explanation three times. The most important section of all articles, particularly specialist ones, is the Lead, (let's face it, many readers will not progress further), and I think more can be done here. For example There are six different types of quarks, known as flavors: up, down, charm, strange, top, and bottom, respectively denoted by u, d, c, s, t, and b. - do we need the notation in the Lead? And, do we need to use "flavor" here; does it help? I would like to see every sentence scrutinised and simplified where possible. I am not suggesting the article should be turned into baby food, but I would like to see more of an effort made with regard to accessibility. Graham Colm Talk 10:31, 4 October 2008 (UTC)[reply]

What is your opinion about this lead.? Ruslik (talk) 15:49, 4 October 2008 (UTC)[reply]
Having looked at the two versions side-by-side, the one on Ling.Nut's subpage, although not perfect, is better. I have changed my mind about the need to mention flavor in the Lead, but I still think the notation can go. Graham Colm Talk 16:24, 4 October 2008 (UTC)[reply]
Well, I updated lead. Ruslik (talk) 16:52, 4 October 2008 (UTC)[reply]
The lead is fine, but I am concerned about the first paragraph. You have simplified it by substituting over-explanation, and in doing this we have actually introduced more confusing termionologies, very early on into the article (color charge, for example, a complex topic that is and should be covered much deeper in the article than a direct reference in the first sentences.) Just my view. —Anonymous DissidentTalk 02:56, 5 October 2008 (UTC)[reply]
Recent edits have improved the article and I am supporting the article now. Particle physics is complex, but the article is an excellent introduction to quarks and their role in forming matter. I would not be embarrassed to see this on the Main Page. Graham Colm Talk 13:16, 5 October 2008 (UTC)[reply]
I thank you for your support, but also for the fine improvements you made to the article in your copyedit. —Anonymous DissidentTalk 13:23, 5 October 2008 (UTC)[reply]
  • (undent) Oppose, even with the new version of the lead. I think this article needs to be thrown back to WP:PHYSICS and completely re-written, hopefully by a collaboration of physicists and non-physicists. Physicists know what they are talking about, but have been dealing with the topic as their job for so long that they end up writing articles that are condensed to the point of opacity, and miss the magic and mystery that interest nonspecialists. Nonspecialists don't understand the topic, and so could introduce significant errors or omissions. I won't be changing my vote, sorry. Ling.Nut (talk—WP:3IAR) 00:59, 5 October 2008 (UTC)[reply]
    • You're opposing because the article lacks the "magic and the mystery", but also because it might contain some errors, which you have not identified. Fine. I don't mind. This is becoming quite silly. This article is written in fairly simple language, from where I stand, while still maintaining a scientific tone; if you were to simply identify certain instances of complication, I could actually work on the article. Instead you call for a "complete rewrite". This provides no room for improvement. In regards to this article lacking "magic and mystery" - we are an encyclopedia, not an amateur science magazine. Our goal is to provide an encyclopedic article built on facts and written in a comprehensive and purely non-biased or non-opinionated way. I therefore do not understand how your point about a lack of some kind of "mystery and magic" is valid. Finally, this article has been looked at by both physicists and non-physicists. I am not a physicist, but Army and SCZenz are (or they certainly have been academically involved in the area, looking at their userpages), and Ruslik0 certainly seems to have some background in physics as well. This is all I have to say. What else can I say? You have, in your previous statement, lain down a brick wall in terms of future improvement and bettering of the article. —Anonymous DissidentTalk 02:56, 5 October 2008 (UTC)[reply]
      • I do not agree with Ling.Nut; this is a very good article and does not need to be re-written or thrown anywhere it just needs a few hours' more work. There is still a little redundancy and confusing prose in the article that non-specialists might find hard to spot because they do not know much about the subject and might think it (the redundancy in particular) conveys some sort of esoteric meaning. The mystery and magic is there—particles appearing seemingly from nowhere and quickly turning back into energy again. Ironically, I think this is the problem, how to describe this to a non-specialist without losing the physics. The article can be improved, please act on my suggestion to scrutinise every sentence and simplify them wherever it is possible. Graham Colm Talk 08:10, 5 October 2008 (UTC)[reply]

(undent) I half don't appreciate the fact that my remarks/concerns are being painted as "silly". This borderline ad hominem is far from constructive, to say the least—and is taking the easy way out. I won't say more than the least, however. :-) As for Graham, if you think it is fixable, then {{sofixit}}. Ling.Nut (talk—WP:3IAR) 08:45, 5 October 2008 (UTC)[reply]

I never called your remarks silly. I referred to the whole debacle. In addition, that single phrase was a fraction of what I was saying; my argument as a whole was hardly ad hominem, as you call it. But arguing semantics isn't going to work here. I plan to read over the whole article tonight and work towards overall simplification. A complete re-write is hardly in order here. —Anonymous DissidentTalk 08:54, 5 October 2008 (UTC)[reply]
FAC reviewers are not expected to fix articles; their job is to review. Having said that, I often help out when I can. I spent the best part of yesterday working on this article and will continue to do so today. Graham Colm Talk 08:59, 5 October 2008 (UTC)[reply]
Comment: “Everything should be made as simple as possible, but not simpler.” (anonymous, attributed to A. Einstein) -- Army1987 ! ! ! 09:50, 5 October 2008 (UTC)[reply]
But it isn't as simple as possible yet. ;-) By "magic and mystery" I think... I think I was saying that the dots are not being connected well in this article, though the info is probably all present. Why are quarks important? I learned in elementary school (ages ago, don't ask) that electrons and neutrons and protons were the smallest things.. now we have quarks, why did we find them? ... and I remember being puzzled as to why protons didn't repel each other.. and quarks are a big part of the mystery of the Big bang, which isn't dealt with here... the article does not do a good job of connecting the dote or of presenting more interesting info... I'm striking my comment about "I won't be changing my vote", in order to remain flexible, but please remember that it is somewhat unlikely that I will do so. The reason I made that statement is not to be obnoxious, but because FAC is not an Article Improvement Area. Believe it or not, I have always strongly supported the idea of reviewers (both FAC and GAN) working extensively on articles; in FAC I worked more than a little on Roman Catholic Church, and I have sometimes almost rewritten whole sections of GAN articles... But we currently have a problem with too many articles and not enough reviewers at FAC, and so substandard articles (not referring to this one) get Passed via fan-club !votes or by one or two very surface skims from one or two reviewers.... so we need to Pass or fail, not Improve, and I think this needs more than a little Improvement... Ling.Nut (talk—WP:3IAR) 11:45, 5 October 2008 (UTC)[reply]
Questions like "why are quarks important?" will always be a matter of opinion, and are way too broad in an encyclopedic context. The fact that they built all matter, a concept which is treated here, is kind of self-evidence for why they are "important". Why did we find quarks? Please refer to the History section; they were found when protons were broken apart and substructures were located inside. Again, "interesting" is a highly opinionated quality of an article; what might be uninteresting to you might be fascinating to me, and claiming that an article is not interesting enough is not really a valid complaint because making a topic more interesting than it is in a specific person's eyes is quite impossible. Lastly, I'd ask you to consider that saying that the article needs "more than a little improvement" is quite a hefty statement, and it would be much more appreciated if you could back up what you are saying with evidence within the text itself (inaccuracies, specific prose issues etc., rather than such abstract questions as 'why did we find them?" [a question whose answer was, as it happens and as I have noted, treated within the article at any rate]). Nonetheless, your clarification is received gratefully, and you are, of course, entitled to as steadfast an opposition as you please. —Anonymous DissidentTalk 12:23, 5 October 2008 (UTC)[reply]
While the question "Why are they important?" might sound fuzzy, it is one of the main points of WP:LEAD. One problem of Wikipedia is that some editors believe that the fact that the topic of an article is technical is a good excuse to make the article incomprehensible (see http://en.wikipedia.org/w/index.php?title=Talk%3AEuler%E2%80%93Lagrange_equation&diff=236955643&oldid=236924288.) (I have since rewritten the lead section of that article, see the old version to understand what that discussion referred to.)
But, in the case of this article, I really can't see how can it be made much clearer than it is now. Often, editors aren't unwilling to make articles accessible, but simply unable to do so. Not everybody is able to write an introductive book about quantum electrodynamics using hardly any mathematics at all, but without serious factual inaccuracies. On the other hand, if somebody manages to make the article clearer without introducing falsehoods, you're welcome to do so. -- Army1987 ! ! ! 13:40, 5 October 2008 (UTC)[reply]
Not to mention that we can't seriously be expected to write an article geared towards people who's high-school education was less than accurate (which is different than having them in mind). It says right there that quarks are one of the two fundamental constituant of atoms. If your high school taught you that neutrons, protons, and electrons were, then they got it wrong (see lie to children, although its very possible that they really believed this to be true since they were told the same thing and never got to do particle physics). If you're puzzled, you can click on atom or proton. Headbomb {ταλκ – WP Physics: PotW} 13:49, 5 October 2008 (UTC)[reply]
What do you think about this? -- Army1987 ! ! ! 14:24, 5 October 2008 (UTC)[reply]
Oppose for now. I'm not an expert but found some errors. "Only the stable up and down flavors occur naturally" contradicts the page on the strange Lambda baryon, which was first found in cosmic rays. Other areas could be simplified - has the top quark actually been directly observed, or is it just that the decay modes are different? One of the links to parton goes to a disambiguation page. Is the 'quack' etymology just a joke, as other accounts say that the 'three quarks' were Gell-Mann's deciding factor. The evidence (or not) for actual existence of quarks should be addressed more. --79.75.111.140 (talk) 13:30, 5 October 2008 (UTC)[reply]
The reference for that etymology is a book about Feynman, so it is not implausible that it was not entirely serious. Maybe someone who's got a copy that book might quote the relevant part? -- Army1987 ! ! ! 13:44, 5 October 2008 (UTC)[reply]
As for all this "direct vs indirect osservation" fuss you and Ling.Nut are making, I simply can't see the point of it. We cannot see single elementary particles with a naked eye, so all observations of them are indirect, in some sense. Well, some are more indirect than others, but there's no need to make a mountain out of a molehill about that. -- Army1987 ! ! ! 13:52, 5 October 2008 (UTC)[reply]
The top quark - it has actually been observed, as is noted in the article in the History section. —Anonymous DissidentTalk 13:48, 5 October 2008 (UTC)[reply]
Cosmic rays create tons of particles. The fact that they found Lambdas (and a ton of others) in cosmic rays is not an indication of stability, but rather an indication that cosmic rays interacting with the atmosphere created particles. Top quarks' been observed since 1995 at Fermilab (or at least I think it's Fermilab). The etymology is not a joke. Headbomb {ταλκ – WP Physics: PotW} 13:49, 5 October 2008 (UTC)[reply]
Fixed the dablink. In regards to the baryon, I have altered the sentence to make everyone happy; it retains its effect while allowing for some exceptions. —Anonymous DissidentTalk 13:50, 5 October 2008 (UTC)[reply]
  • In the lead it says that the u and d quark were "discovered" in 1968, then the rest from 1974 (charm) to 1995 (top). This forgets about the strange quark. Something should be mentionned about that one.Headbomb {ταλκ – WP Physics: PotW} 14:04, 5 October 2008 (UTC)[reply]
    • I've reworded it; strange weren't actually observed in '68, but their existence was validated by the existence of the other two because it was necessary to the model, as well as because the concept of strangeness was already accepted (cf Kaon). This is discussed further on. —Anonymous DissidentTalk 14:30, 5 October 2008 (UTC)[reply]
  • Zweig originally called them aces. Something should be mentioned about this too. Headbomb {ταλκ – WP Physics: PotW} 14:04, 5 October 2008 (UTC)[reply]
I have put a sentence with a reference about this on the Talk page. Graham Colm Talk 14:19, 5 October 2008 (UTC)[reply]
Integrated; thanks for the ref. —Anonymous DissidentTalk 14:38, 5 October 2008 (UTC)[reply]
@Headbomb— the lies to children bit was well-intended but way off the mark; "there was little evidence for their existence until 1968" which would have been one year or perhaps two before I started elementary school, and four or five before I studied atoms. I'm not aware of elementary schools that keep abreast of the latest developments in particle physics. ;-) @Anononymous Dissident—top quarks have been directly or indirectly observed? Plus I think my remarks have been pretty specific, especially when the old lead, my version of the lead, and the revised version of my version (which is currently atop the page) are compared... @Everyone: I actually don't fully support the lead as it stands, or even my own version (from which the current one was drawn). My version was intended to show the direction of change that I thought would be good, not to be the Final Version (TM).. I think the article should go back to WP:PHYSICS and be rewritten top to bottom. 'Nuff said. Ling.Nut (talk—WP:3IAR) 14:35, 5 October 2008 (UTC)[reply]
Fair enough. Enough said indeed. Your oppose is noted. —Anonymous DissidentTalk 14:40, 5 October 2008 (UTC)[reply]
I'll just point out that myself, SCZenz, Ruslik0, and Army1987 are all members of WP Physics... Headbomb {ταλκ – WP Physics: PotW} 14:43, 5 October 2008 (UTC)[reply]

Support: With the inclusion of the aces and strange quark discovery, I'm happy with the content of this article and with the way it's written. Headbomb {ταλκ – WP Physics: PotW} 14:37, 5 October 2008 (UTC)[reply]

The lead says that free quarks are never observed in nature. However the t quark doesn't hadronize... Perhaps SCZenz could offer some insight here. I withdraw my support until this has been addressed.Headbomb {ταλκ – WP Physics: PotW} 04:49, 6 October 2008 (UTC)[reply]
I think this addition clarifies things. You still don't directly observe free top quarks; you deserve their decay products. The top quark would hadronize too, if it ever lasted long enough. -- SCZenz (talk) 06:19, 6 October 2008 (UTC)[reply]
I know that. What my concern was what should the lead say about it? Headbomb {ταλκ – WP Physics: PotW} 16:34, 6 October 2008 (UTC)[reply]

Oppose: You have to think about who your audience is. I believe that it is possible to say things about quarks that are understandable by a high-school student who knows about the structure of an atom. It is okay for parts of the article to be more technical, but that high school student ought to be able to read at least the beginning of the article with benefit. As it stands, there's no chance of that -- right from the start it's leptons and hadrons and other advanced physics cruft. Looie496 (talk) 23:38, 5 October 2008 (UTC)[reply]

I've reworked the second statement to note that quarks and leptons are the basic components of all matter. That is way enough, and it explains very clearly what quarks are. If the reader reads on, they are met with an easy to understand explanation that there are six different types "or flavors" of quarks. They are still with us, because understanding that things come in different varieties is an infant's concept. We then learn that only up and down varieties are stable, and the rest can only be created in particle accelerators. Stability is a concept I learned in the fifth grade, and a particle accelerator is something most people have heard of, considering recent events. Then we have the sentence about the up and down being very common - easy. The next statement deals with antimatter, a subject that needs to be tackled but which might be hard for some to understand. Still, we have noted that they are like the quark's archenemy.
Next para, we see that quarks cannot be isolated because of color confinement, with a juicy link for the latter. What that is isn't important in the lead, and a cursory look at the TOC will reveal that it is covered further down. Next sentence hadrons are explained, and then we see that there are two varieties of hadron, just before an explanation of how many quarks and antiquarks there are in each. Again, simple as pie, no ambiguity even for a toddler. A little further on, we find out that the protons and neutrons, two things everyone over the age of probably 10 has heard of, are hadrons and are therefore made up of quarks. Anyone who was feeling slightly lost, which I doubt, is now back on the boat. The next statement after that is fairly straight forward, and even implied by the fact that quarks cannot escape from hadrons.
The final paragraph is a simple history section, that uses no jargon in its expression.
Now, where was the difficulty in that lead? I just gave a sentence-by-sentence analysis of that lead, and explained quite clearly why everyone could understand it. The rest of the article eases into concepts, with reference to the simple-to-comprehend lead. —Anonymous DissidentTalk 02:31, 6 October 2008 (UTC)[reply]

Oppose: I think it's an important article, and I'm glad someone has re-worked it, but in the present state, I don't think it's FA standard (yet). My main objection is that the article doesn't meet 1b - there are too many crucial aspects that aren't even mentioned. Also, it looks to me like there are some problems with what is there.

  • Curious omission: the standard model of particle physics is mentioned in the lead and in the caption for the lead image only, and then never again. And while the weak interaction is mentioned, the fact that this introduces new states (right-handed different from left-handed) is not, and neither is the mass mixing issue (see comment on Higgs, below).
  • Curious omission: not even a hint of the group theory basis of the quark model?
  • Curious omission: Yang-Mills theories and, more generally, non-Abelian gauge theories not mentioned at all.
    To discuss all these things you will need to introduce complicated math into the article. Yang-Mills theories require writing the lagrangian, for instance. I am not sure that even majority of physisist will understand it. These topics are better to be dealt with in special articles. Ruslik (talk) 06:29, 6 October 2008 (UTC)[reply]
  • Curious omission: Nothing about the quark-gluon-plasma.
  • Description of the parton model: could use some words on what it means that "the proton had substructure".
  • Curious omission: no mention of what the parton model has to do with asymptotic freedom. (Which is mentioned once, later.) In particular, the lead says that "Since quarks are not directly observable, their properties can only be deduced by experiments on hadrons." - but that's the whole point, isn't it? At high energies, it looks as if you have free quarks just coasting along there.
  • In the section on mass, the Higgs mechanism is mentioned only as an afterthought - why? Surely, in the standard model, this is how quarks get their non-zero rest mass in the first place?
  • The paragraph about spins is a bit uneven. It explains in very elementary terms some properties of spin, but, for instance, doesn't mention what half-integer spin entails: the Pauli principle, in other words: what makes matter matter. It doesn't even mention that half-integer spin is what all matter particles have in common.
  • The last sentence is misleading: "The quark's spin value contributes to the overall spin of the parent hadron, much as quark's electrical charge does to the overall charge of the hadron. Varying combinations of quark spins result in the total spin value that can be assigned to the hadron." - several problems with that. At an elementary level, because spin is directional there are more ways of combining elementary spins than there are for simple scalar charges. The more advanced problem is that the combination of valence quark spins doesn't reproduce the proton spin. Which is why we've had experiments like HERMES at the HERA particle accelerator. See, for instance, this article.
    You overcomplicate the issue. The spin of the hadron is sum of spins of the quarks: 1/2+1/2+1/2=1/2 or 3/2. The structural functions discussed in the paper does not influence this result. They are only important for hadron's magnetic moment. Ruslik (talk) 06:29, 6 October 2008 (UTC)[reply]
  • "The system of attraction and repulsion between quarks charged with any of the three colors (...) is as follows: a quark charged with one color value will be attracted to an antiquark carrying with the corresponding anticolor, while three quarks all charged with differing colors will similarly be forced together. In any other case, a force of repulsion will come into effect." - that makes it sound more simple than it is. If, say, you have three quarks, each with a different color, and take the symmetric combination, you'll end up with a repulsive force. Also, for a symmetric state with two quarks with two different colors, you get an attractive force.
  • "Composed of one d and two u quarks, the proton has an overall mass of approximately 938 MeV/c2, of which the three quarks contribute around 15 MeV/c2, the remainder is from the energy of the gluons." - 15 MeV/c^2 sounds very low. I remember coming across higher numbers (quark rest mass plus kinetic energy contributions). Is that number recent?
  • "Gluons are constantly exchanged between quarks through an emission and reception process. These gluon exchange events between quarks are extremely frequent, occurring approximately 1024 times every second." - I'm very skeptical about the number given. After all - and that should be stated here! - the exchange picture is perturbation theory; whatever happens inside a hadron is highly non-perturbative.
  • "In this way, an infinite amount of energy would be required to wrench a quark from its hadronized state." - but that's not what happens, right? If you really were to pull a single quark away from its partners, there would be pair creation once you have invested sufficient energy, and you would be left with two hadrons instead of one.
  • "Those quarks that make up the core of the hadron are called valence quarks." - core sounds a bit literal. As if everything else is going on around that core.

Some other issues:

  • Lead seems to be too technical - it should be understandable to the average curious reader. I don't think the current version meets that standard. It tries to put all the technical terms in there, but doesn't explain them. For instance: strong force is introduced, and in a way that assumes that the reader knows that the color charge implies interaction via the strong force, but it doesn't say what the strong force does. It doesn't even say that the binding-together of quarks to form hadrons is due to that strong force.
  • Since the lead is supposed to introduce no concepts that aren't explained in detail later on, I don't think it should have references.
  • I don't quite know what to make of "which was found to have a mass approximately equal to that of a gold nucleus, around 200 times heavier than the hadron it was thought to form." - especially as the reference given for that sentence doesn't appear to contain any statement like that.
  • "A quark can only hold a charge of fractional or non-integer value, either −1/3 or +2/3 (measured in elementary charges), but the charge of an antiquark can be either" - sounds a bit weird. After all, the "but" doesn't address the "can only", as one would expect from the sentence structure.

Markus Poessel (talk) 02:33, 6 October 2008 (UTC)[reply]

  • Note; the article still relies on marginal sources, as outlined earlier, such as antonine-education and hyperphysics; also, missing publishers. SandyGeorgia (Talk) 02:41, 6 October 2008 (UTC)[reply]
  • Comment I take on board the suggestion that my comments are too vague. I apologize... Monday (today) and Tuesday are my busiest days at work... I'll try to have an exhaustive (and exhausting) commentary that's as close to line-by-line as possible... perhaps I can do it Wednesday or Thursday, then post it all here in one fell swoop. Again, I apologize for the vagueness. Ling.Nut (talk—WP:3IAR) 02:39, 6 October 2008 (UTC)[reply]
  • Statement @Markus: what a comment. I plan to tackle every bullet over the next dayish. Please bear with me. @Sandy: I was sure I had every publisher marked. —Anonymous DissidentTalk 02:50, 6 October 2008 (UTC)[reply]
    • To be honest, most of your concerns, Markus, are beyond my experience. I have asked SCZenz to take a look. Again, please bear with me. —Anonymous DissidentTalk 06:22, 6 October 2008 (UTC)[reply]
      • I'm certainly willing to bear with you. Again, I think it's great that someone's resolved to take this article to FA. And I apologize for merely pointing out the problems instead of fixing them myself – I'm exceptionally busy for the next few weeks. Markus Poessel (talk) 12:54, 6 October 2008 (UTC)[reply]
  • Closing notes: with one Support struck, and the level of issues mentioned by domain experts who have opposed, I think this work will best proceed off-FAC. I hope it will return to FAC with more solid sourcing, and a much clearer lead and more context about the significance of quarks and their discovery, and with less definitions and more context in the lead. SandyGeorgia (Talk) 00:47, 7 October 2008 (UTC)[reply]
The above discussion is preserved as an archive. Please do not modify it. No further edits should be made to this page.
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