Talk:Standard Model

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[edit] Leading Paragraph

Half of the leading paragraph (one long sentence) is about how the Standard Model is not a theory of everything. This sentence seems unnecessary since neither the blurb above it nor the rest of the article makes it explicit that it is approximately a TOE. Neither the general public nor the researchers in high energy physics mistake the standard model to be one. I feel that this sentence needs to be moved to a separate section elsewhere in the body of the article (preferably at the end), where extensions beyond SM and theories including gravity may be discussed. --TriTertButoxy (talk) 00:59, 25 March 2008 (UTC)

[edit] Review request and other remarks

There is a table listing the respective values for measured and predicted values of particle masses, for the W boson 80.398±0.025 and 80.3900±0.0180, for the Z boson 91.1876±0.0021 and 91.1874±0.0021.

I've never seen a calculation predicting these values. Rather it is known that the standard model describes masses as free parameters. Can anybody help me ?

—Preceding unsigned comment added by 89.60.187.242 (talk) 09:59, 20 January 2008 (UTC)

Add a section on history of the standard model's discovery, including links/citations to original papers. C9 (talk) 04:25, 7 January 2008 (UTC)

Could someone please review the noncommutative standard model page and either merge the relevant content, or propose deletion of that page? I don't know enough about the particle physics community to know if that material is noteworthy. Vessels42 18:16, 14 December 2006 (UTC)

Shouldn't the elementary particles also be mentioned, in addition to the forces? I.e. two quarks, electron and neutrino, and then two more families like that. AxelBoldt

Talk:Standard Model/Sandbox - formatting experiment

Shouldn't we mention the Minimal Supersymmetric Standard Model?

Go to http://www-wisconsin.cern.ch/physics/files/r20401.pdf. It has proof that Higgs particles have been found.

Perhaps it would be helpful to include a cross reference to the photino in the See Also section?

Be bold! If you think it belongs there, add it! moink 07:42, 7 Mar 2004 (UTC)
(p.s. yep. it appears i'm following you around:) )
Confusingly, this new model is still called by the same name as the old one: the Standard Model.

Removed this sentence. The Standard Model is a working model, not a fundamental theory. As such it is constantly refactored to account for new data and new ideas. The Standard Model is the state-of-the-art in physics—the model is expected to evolve.
—Herbee 11:27, 17 Sep 2004 (UTC)

User:Agasides added the "varying physical constants" material back to the article, saying Its not a speculation. Go find a laboratory similar to Webbs laboratory, and repeat the experiment.. Unfortunately, it is a speculation, very much outside of the mainstream of physics. That doesn't mean it's wrong, just that it hasn't met the burden of proof necessary to convince the rest of the physics community of such a radical phenomenon. Unconfirmed speculations belong on arXiv.org, not Wikipedia. Anyway, as [1] makes clear, the present experimental data implies that even if the value of constants like α are actually position-dependent, the variation is unbelievably tiny; it's hardly a repeatable lab experiment. -- CYD

[edit] Accessibility

This article may be too technical for a general audience.
Please help improve this article by providing more context and better explanations of technical details to make it more accessible, without removing technical details.

Is the best way to add material for particle physics novices to simply expand this article, or to add a companion article, a la Special relativity for beginners? -- Beland 00:54, 16 August 2005 (UTC)

Obviously this article gets too technical too fast for a general encyclopedia, but most of the physics articles I've seen in Wikipedia have the same kinds of problems. There is a lot of good information but it isn't put together in a very insightful way. The problems with the Dirac Equation article are tons worse than this "Standard Model", which at least gets to the point. The Dirac equation looks like someone is trying to write a physics textbook. Maybe Wikibooks would be a good place for that stuff? Non-specialists probably want to know what the standard model is and why it's important rather than immediately get lots of links to fermions and bosons etc. Some person who wandered in to this article hoping to find out something about "standard model" would be a little disappointed or bewildered. I'm not too sure what to do about it though.--DannyWilde 01:25, August 16, 2005 (UTC)
I'd like to see a "history of the standard model" section, although that'd be pretty close to "history of particle physics". - mako 02:02, 16 August 2005 (UTC)
I'll try to add in a significant amount of detail, mostly at a pedestrial level. There is a lot of interesting facts about the Standard Model that elude even the authors of most advanced texts on this topic, and numerous other details that are rarely mentioned in any book on quantum field theory, much less in popularized accounts of the theory.

[edit] The Standard Model is wrong about neutrinos

The Standard Model says neutrinos are mass-less and therefore move at the speed of light but neutrinos do have mass, because they do change over time(a particle moving at the speed of light can not change because it's clock has stopped). This was proved by experiment after the number of expected neutrinos from the Sun and in the atmosphere did not appear in the detectors used.

NOVA just released a program on this. "In this program, NOVA probes the secret ingredient of the cosmos: swarms of invisible particles that fill every cubic inch of space and just may explain how the universe was created. Trillions of ghostly neutrinos move through our bodies every second without us noticing a thing. Yet without them the sun wouldn't shine and the elements that make up our world wouldn't exist. This program explores the 70-year struggle so far to understand the most elusive of all elementary particles, the neutrino.

Narrated by British actor Juliet Stevenson, "The Ghost Particle" is the story of a discovery that altered scientists' understanding of what the universe is made of and how it was first formed. NOVA accompanies scientists into the laboratory, revealing astonishing footage of bizarre experiments. Computer animation brings to life the neutrino particle, which is at once invisible and yet utterly essential to all life.

The program first takes audiences back to 1930, when Austrian physicist Wolfgang Pauli wrote to his colleagues about the phenomenon of radioactive decay. The experts were puzzled by a missing bit of energy that could not be accounted for in their picture of how a radioactive atomic nucleus decays. Pauli suggested that an exquisitely tiny, previously unknown particle had to exist to account for the missing energy. The problem with this theory, however, was that there was no hard evidence of neutrinos' existence.

It seemed to be an impossible investigation. Neutrinos have no electric charge, making them invisible to ordinary detecting equipment. Truly poltergeists among particles, they can pass directly through thousands of miles of solid matter without slowing down. Yet every element vital to life, including carbon and oxygen, is made by a chain of nuclear reactions that would be impossible without neutrinos. They are an essential ingredient of the universe, and catching these neutrinos became the ultimate scientific quest (see Case of the Missing Particles).

NOVA sits down with Professor John Bahcall and Nobel Prize winner Ray Davis, two men determined to solve one of the biggest puzzles in particle physics. In the 1960s, they began their scientific adventure with a daring underground experiment that few believed could succeed. Vindication for both men is a long time in coming ... but come it does." The transcript will be avaible soon at http://www.pbs.org/wgbh/nova/transcripts/3306_neutrino.html.Timothy Clemans 18:51, 22 February 2006 (UTC)

There are a couple of mechanisms by which to add neutrino masses to the Standard Model, and although they are not official parts of the Standard Model, they are certainly consistent with it. Thus to say that the Standard Model is wrong about neutrino masses is overstating the case a bit; neutrino masses can be accomodated without changing anything else. As I understand it, the main reason one of these mechanisms hasn't been added officially to the Standard Model is that physicists don't know which one is correct yet. -- SCZenz 19:13, 22 February 2006 (UTC)
I would only say a standard Dirac-style neutrino is really consistent with the Standard Model. A Majorana-style neutrino would definitely be new and weird and beyond-the-SM. Thankfully, there's no evidence for that. -- Xerxes 20:35, 22 February 2006 (UTC)
The Standard Model, as far as I can tell, is just a humungous ad hoc Lagrangian that happens to explain everything we've ever seen in particle physics—how, then, is one type of new term consistent and the other weird and different? (I ask this out of ignorance, rather than disagreement.) -- SCZenz 22:25, 22 February 2006 (UTC)
Actually, it's neither humongous nor ad hoc, but is merely presented that way in most treatments. It can be written in one line, with the right representation (and factoring) of the fermion space; the latter, in turn, exposing the high degree of regularity of both the fermion and boson spectra and regularities in the Standard Model, itself, that receive little or no airplay. The Lagrangian is written out in full here (http://federation.g3z.com/Physics/index.htm#StandardModel) with graphic depictions of the regular structure of the fermion and boson spectra that are quite striking. -- Mark, 5 April 2007

[edit] Symbols in the Table section

What was wrong with my edit? The symbols I used may have a slightly different meaning, but they are completely standard. Insisting on the charge conjugation symbol would be too pedantic even for a field theory classroom, which Wikipedia is not. Furthermore, my edit was consistent with the notation at List of particles, Neutrino, Meson, and who know hows many other Wikipedia articles.

Given all that, I'll revert back to myself. Melchoir 21:53, 23 February 2006 (UTC)

It's not pedantry, it's just correctness. The field/field-bar symbols imply that we're talking about full Dirac spinors, which we clearly are not, given that the columns are headed according to field chirality. I agree that field/field-bar symbols are prettier, if you want to use that notation, the rest of the table needs to be changed so that the whole remains correct. -- Xerxes 22:21, 23 February 2006 (UTC)
I don't think we should interpret the symbols as Dirac fields anyway; they're just names. Using an overbar on the name of a particle is not the same as Dirac adjointing a Dirac spinor; I don't know what would happen if you complex transposed the letter "u" and multiplied by \gamma^0. It's unfortunate that these meanings have the same notation, but there you are.
As for field chirality, I'm not sure why the table needs to say "left-handed" at all. In a (low-energy) experiment or calculation, you have to deal with the full Dirac electron/up/down anyway; the neutrino is still up in the air, but I don't personally understand those. Melchoir 22:40, 23 February 2006 (UTC)
As far as I know, q-bar (with q being whichever letter) is the standard symbol for an antiquark among experimentalists, or anyone else who isn't doing something with extreme rigor. Am I missing something? -- SCZenz 22:53, 23 February 2006 (UTC)
I see what the problem is now. Why the hell are the columns headed by field chirality? Who on earth is this for? -- SCZenz 22:53, 23 February 2006 (UTC)
It's a very standard way of enumerating the degrees of freedom of the Standard Model. This way, you can see the representation structure of the theory. It's helpful for working out anomalies and that sort of thing; personally, I feel that this kind of table encodes much of the beauty of the structure of the SM. Anyway, the point being that the table does not list realistic particles; specifically it does not assume mixing of chiralities. The notation has to reflect that or the table has to change. -- Xerxes 23:22, 23 February 2006 (UTC)

If the table is primarily meant to exhibit the representations, that makes sense to me; it's a purpose not served elsewhere. Why don't we:

  • Rename the table: "Fermionic degrees of freedom" or somesuch
  • Preface the table with a prominent link to List of particles
  • Delete the "mass" column entirely
  • Use whatever symbols you like

I think the table should also be a bit smaller, but that's less important. Melchoir 00:18, 24 February 2006 (UTC)

Good ideas! I think we should also add a table of "free parameters of the Standard Model", which is where those masses (Yukawa couplings) actually belong. I'll work on that later today. -- Xerxes 16:10, 24 February 2006 (UTC)
Actually, when the masses are removed from the table, we can collapse all three generations into eight rows. Melchoir 21:16, 24 February 2006 (UTC)

I should know these things cold, but at risk of flaunting my ignorance, the hypercharge line on the table looks to me like it's calculating the quantity which, while often known as hypercharge, corresponds to the Wikipedia article weak hypercharge (and, then it seems to be divided by 2 with respect to the definition there). Also the link on the word hypercharge seems to go to the hypercharge page, and not to the weak hypercharge page. Or maybe I'm wrong?JarahE 17:51, 27 April 2006 (UTC)

Looks like you're right to me, tho I'm unsure which factor of 2 is more conventional. -- Xerxes 18:31, 27 April 2006 (UTC)
You are correct that the "Hypercharge" is actually half of the Wikipedia article's Weak hypercharge. I have made the requisite changes. (I know there are some that insist that the "modern" usage is to simply call it "hypercharge", but, especially since "hypercharge" was being auto linked to [strong] hypercharge, it most certainly wasn't helpful. In addition, the factor of two error, that's been there ever since 8 August, 2003, made it very difficult to determine what was actually meant to be there.) -- DWHalliday (talk) 20:38, 23 March 2008 (UTC)

[edit] References

Is Deep Down Things really a reference used to verify this material, or is that an ad I see? Melchoir 04:19, 29 April 2006 (UTC)

[edit] Illustration

Could someone come up with a better illustration than the existing wall-poster? Much of the text is impossible to read, even at high resolution, and in my view the image adds little or nothing to the article at normal size.--MichaelMaggs 19:08, 14 August 2006 (UTC)

[edit] problem with the tables ?

Hi,it seems to me there are some problems with the tables

  • particles and anti-particles should have opposite additive quantum number but there it seems no antiparticle forms a doublet under the weak interaction! The positron and the electric anti-neutrino should transform into each other under SU(2)weak and have non vanishing weak isospin numbers, no ??
  • hypercharge is a concept defined for hadrons but the table gives non vanishing hypercharges for letpons as well ? Isn't there a confusion between hypercharge and weak hypercharge here (hadrons having both of them) ? I think it would be better to display weak hypercharge rather than hypercharge.

As I presume these tables must have been crossed checked a certain number ot times I prefer to ask and get comments before changing anything to it. LeYaYa 13:19, 7 October 2006 (UTC)

I agree the table needs some major revising. And by the time the LHC gets booted up standard model might turn out to be completely wrong.-MJH 20:24, 8 October 2006 (UTC)

completely is too much a statement as one cannot undo the previous successful experiments which confirmed many aspects of the SM (unless you doubt the conclusions of the experiments at the same time but that's starting to be a lot of mistakes :) ). The only remaining piece is the Higgs boson but it has already started to show up at the end of LEP even though not enough to give conclusive results. Nevertheless, even if one can argue that SM is incomplete it would be highly difficult to prove it wrong and be consistent with current observations. regards, LeYaYa 19:48, 10 October 2006 (UTC)
LeYaYa, if you look at the top of the table, you will see that this is a table for the left-handed fermions of the standard model. most books do not include a table for the right-handed particles because these can easily be obtained from the left-handed table since, as you pointed out, there is a symmetry between the quantum numbers. Left(right)-handed particles and right(left)-handed anti-particles have oposite quantum numbers.
To answer your other point, what was once called a weak hypercharge is simply called hypercharge in modern days, and what used to be simply called hypercharge must be qualified somehow (either as flavor hypercharge, or in some other way). The reason for that is the fact that weak hypercharge is a gauged symmetry of the standard model, and therefore much more proeminent then the flavor hyprcharge which is an accidental symmetry due to the fact that the quarks u,d,s all have relatively small masses. Dauto 02:26, 13 May 2007 (UTC).
You may well be correct that among certain circles the "modern" usage is to simply use "hypercharge" when referring to weak hypercharge. The problem, here is twofold: 1) The "Hypecharge" header auto linked to (strong) hypercharge, rather than what you claim; and 2) the values are half of what the correct weak hypercharge values should be. What bafles me is how this has remained uncorrected since its introduction on 8 August, 2003! (I have made the requisite changes.) -- DWHalliday (talk) 20:47, 23 March 2008 (UTC)

The main table is not good. It's way too long, I find the use of both weak charge and weak isospin confusing. The neutrino information implies that the neutrinos are Dirac rather than Majorana (which is the current opinion) and there certainly isn't a limit of 2 eV on their masses. I will delete the right handed neutrinos, but I think that this table isn't necessarily up to snuff on several different fronts. jay 17:21, 13 May 2007 (UTC)

Having both weak isospin and weak charge is confusing, so I removed the weak charge. I also changed the masses to 3 sig figs (where it is known) since errors aren't being quoted. I changed the names of the antiparticles in order to reduce the possible confusion of ( bar(t) )^* = t. jay 19:06, 15 May 2007 (UTC)

Having both the weak isospin and the representation dimensions is redundant, that`s true. (beats me why some people like calling these dimensions "charge" ). But it is important to let the readers know at a glance which particles are grouped together in a given representation under the weak SU(2) transformations. As it is, these tables are failing to do that. Any sugestions?

Defense of Table The table is actually cited by others as the best part of the page! James Stein, of California State University, in his book 'How Math Explains the World' (HarperCollins, 2008), says "[Wikipedia has] an excellent short exposition of the Standard Model, along with a beautiful chart that puts the periodic table to shame. You have to click several times on the chart before you get to a readable resolution, but it's worth it" (p.40).24.63.20.31 (talk) 15:52, 10 May 2008 (UTC)Michael Ringel

[edit] for the lay reader

Here's a 2003 critique of the Standard Model and another one. Billbrock 09:32, 30 October 2006 (UTC)

Critique is the wrong word here. Everyone agrees it's a great theory which makes astoundingly accurate predictions, and everyone also agrees that it has some technical holes that ought to be patched up by a new theory with new particles or other observables. Gordy Kane is an advocate of some particular ways of patching those holes, and what he has to say will be interesting. -- SCZenz 17:37, 30 October 2006 (UTC)
"Critique" may not be the ideal word, but it's OK; cf. Moby-Dick. Billbrock 19:35, 30 October 2006 (UTC)

[edit] Tests and predictions

This section is pretty bad currently. The W boson had been discovered before the standard model, I believe. And the existence of the charmed and top quarks is not really a prediction of the standard model as such. The prediction of the Z, with the correct mass relative to the W, was an extraordinary achievement, and should be emphasised. Some of the successes of QCD also need to be included. Shambolic Entity 02:12, 5 November 2006 (UTC)

[edit] Challenges to the Standard Model.

I think the main Challenge to the Standard Model is to find the Higgs particle. Since it has not been found, the status of the model or better the theory is unconfirmed. Not mentioning this as the main challenge on the page is misleading. Aoosten 22:16, 9 June 2007 (UTC)

Isn't a neutrino with a mass a greater problem? That is: the solar-neutrino problem, that has now been solved by assuming the neutrino having a mass... Said: Rursus ☻ 07:17, 5 February 2008 (UTC)

[edit] Revamping of Article

As you can see, I've recently begun a personal project of rewritting and reorganizing this article. So far, I've rewritten the first third. I hope the new version is easier to follow for nontechnical readers -- please check this.

Now, In the middle of the article there's a series of three huge tables of fermions which I find exceedingly unaesthetic. I've decided to create 'summary' tables of particles within each subsection, which I think is easier to follow.

Since this is an encyclopedia, I am completely for the idea of having a detailed "master" table of all particles (which the three giant tables seem to strive to be). But, can somebody (who's adept at making tables) make a nicer looking one that we could put at the end of the article so that it doesn't look so intimidating and put off any potential readers who might be curious about the state-of-the art theory of physics? —The preceding unsigned comment was added by TriTertButoxy (talk • contribs) 06:02, 6 January 2007 (UTC).

I left a note on your talk page: great work on the article... but if you're going to rewrite the whole thing, could you cite your sources as you do it? It's important for verifiability. Thanks. -- Rmrfstar 18:19, 6 January 2007 (UTC)
All of the material I've written is 'common' knowledge among particle physicist, and so, my citations would come from one (text)book. How do you propose I should do the inline citations from the book? Or would you prefer if I got lots of different texts on particle physics? TriTertButoxy 18:03, 15 January 2007 (UTC)
Wikipedia:Scientific citation guidelines#Uncontroversial knowledge should help you. As it says, "Therefore, in sections or articles that present well-known and uncontroversial information ... it is acceptable to give an inline citation for one or two authoritative sources at the start". This is followed by a good example of how this is best-done. -- Rmrfstar 18:13, 15 January 2007 (UTC)

Just as a minor note...there are no explanations for the terms "SU(3), SU(2), and U(1)" and all that in the article. -RunningOnBrains 05:11, 26 February 2007 (UTC)

I've made another giant edit. This time the TOC outlines the material that needs to be added.--TriTertButoxy (talk) 06:20, 2 March 2008 (UTC)

[edit] Major rewrite? The article is much worse

It seems to me that the changes made by User:TriTertButoxy could stand some review. The articleis now without the CPEPweb diagram, the "Force-mediating particles" diagram and the list of fermions and their properties. There are now many empty sections in the article. All you have done is add a messy outline or a "todo" list into the article text. I do not think that anybody else wants this article to simply be a long wish-list of "other SM-related articles and sections that we would like to see". It might be that we need a History of the Standard Model article, but that is separate. There must be a place in the Physics WikiProject for a "todo" list like this.

Even the lead paragraph that TriTertButoxy put in was highly self-referential and almost apologetic about what the intend of this article was. I removed that, but then stopped. If you intend to herd our editors in a particular direction, then do so on this talk page. In the future, when making such edits on a copy in your userspace, please at least use the {{Inuse}} template.

This represents a serious degradation in the quality of the article. I think that TriTertButoxy should demonstrate in writing that why he did what he did serves any purpose to improve the article quality by stating his goals in the changes he made. I am going to wait a few days for input from others, but I am inclined to revert this rewrite and then come up with set of goals for what we want the article to be.--Truthnlove (talk) 07:45, 2 March 2008 (UTC)

I vote for a revert. --Michael C. Price talk 01:54, 5 March 2008 (UTC)
I decided to re-implement the information I thought was important over at Elementary particle and Fundamental interaction. I will rarely return here. Maybe that is how the information should be organized.--Truthnlove (talk) 07:11, 3 March 2008 (UTC)
Sorry; I honestly thought I was being bold. This was my second major rewrite of the article -- and despite the sucess of my first rewrite, it looks like I went a little overboard this time. I really didn't mean to ruin the article. I also didn't mean to make the introduction sound apologetic. I think the statement "presently, it represents the summary of vast data collected by thousands of natural scientists across several disciplines since the beginning of modern science, culminating in the electroweak unification and on the discovery of asymptotic freedom in quantum chromodynamics" made it sound that way. Though, I'd like to make it clear that the standard model is a theory of such scope. The diagram I removed summarized the interactions between the particles, and was in fact created by me. After some thought, I felt that it was quite misleading, since it suggested that gluons and photons can't interact with the higgs boson. They actually can (dynamics are governed by the quantum action not the classical one). As for the table listing the quantum numbers and masses of all the particles, I intend to create another table in the future that doesn't look so overwhelming. I got rid of the passage regarding the anthropic principle because the standard model isn't a theory of everything, whose parameters need any explaining. Oh well... Truthnlove, your comments on my talk page were rather harsh, and I would have much preferred an immediate reversion of the article instead of such negative critisism. Though I do see my mistake. —Preceding unsigned comment added by TriTertButoxy (talk • contribs) 03:45, 4 March 2008 (UTC)

If the deleted material on a number of topics (including diagrams) is not restored I suggested reverting the article. Being told that it may reappear in the future is not good enough. --Michael C. Price talk 01:52, 5 March 2008 (UTC)

I have restored the lost particle diagrams etc. Please do not start future "rewrites" with massive deletions without finishing the job properly.--Michael C. Price talk 13:46, 8 March 2008 (UTC)

[edit] Weak Interactions

The figure in subsection Force Mediating Particles doesn't show up a W + W − Z-coupling, but SM provides such a vertex. May anyone change the graphic by adding the missing line? --CHamul 09:02, 16 January 2007 (UTC)

Thanks! It's fixed now. TriTertButoxy 00:10, 17 January 2007 (UTC)

[edit] Challenges to the Standard Model

This ridiculous statement appears "Alain Connes has shown that the standard model can be derived from general relativity by generalizing Riemannian geometry to noncommutative geometry." That would be amazing! Would someone please fix it to read properly? I don't know what was intended. If I see it there next time I check, I'll delete it. 06:43, 26 March 2007 (EST)

You can check, for example, hep-th/0111236 131.111.8.96 20:13, 29 March 2007 (UTC)
I wrote the statement that you qualify ridiculous. The statement is not mathematics and I do not pretend to be able to prove it. Neither is Einstein's derivation of general relativity provable. However both theories, Einstein's and Connes' are confronted with experimental numbers. I thought that this is what physics is about. If you have a different criterium, please tell me and I may try to satisfy you before you check next time and delete me. Schucker 22:51, 1 May 2007 (UTC)
I have read hep-th/0111236 and this article is not very pedagogical or conclusive -- in particular it does not definitively support the claim given in the wikipedia article. I know that the statement in the wikipedia article is not the consensus view of physicists and do not believe that such speculative statements should be listed in the Standard Model article. jay 18:30, 4 May 2007 (UTC)
I agree on; reference to Alain Connes and that standard model is derivable from general relativity should be removed, as this claim is totally out of mainstram physics. IlkkaP 21:29, 28 May 2007 (UTC)

[edit] Gauge group???

How come there can be an article on the Standard Model and not mention the gauge group \rm SU(3)\times SU(2)\times U(1) ??? 131.111.8.96 20:15, 29 March 2007 (UTC)

[edit] Accessibility

I've had a go at reworking the overview "Standard Model" section of this article lightly, with the aim of maiking it more accessible to non-physicists, without "dumbing down" the good quality of detail.

We could do better, make the statement more accessible to people in general. Hopefully the edits are good ones. I've tried to tweak the main "Standard Model" section to introduce the components and their roles, and put the Standard Model in a context, so readers can learn easier, rather than just describe their spin etc for physicists alone. Hopefully its a Good Thing.

Main edit areas:

  1. "Overview" paragraph at the start of the "Standard Model" section, to contextualize better.
  2. Language use: eg,
    • Old: "For pedagogical purposes, the description of the Standard Model is divided into three parts",
    • New: "For ease of description, the Standard Model can be divided into three parts."
  3. Clarification that "odd" names like "spin", "charm" and "flavor" are names for properties of particles (obvious in physics, not obvious to newcomers seeking a basic overview or understanding of what the Standard Model is)
  4. Clarification what a "force mediating particle" is - how the standard model interprets forces as being due to the exchange of particles. Essential background knowledge needed to make any sense of the term "force mediating particle".
  5. Higgs Boson - was not described at all, save in terms of spin, hopes of discovery and that it plays a "unique" (but not described) role. Brought the barest basics over from that article to fill the gap.

DIFF.

Please check edit for anything inadvertantly dumb! :)

FT2 (Talk | email) 14:01, 1 July 2007 (UTC)

[edit] Could someone expand on the concepts of "left-handed" and "right-handed"?

The terms "left-handed" and "right-handed" appear with no definition in the discussion of the gauge-bosons. Could someone explain this concept, or perhps just link to the entry on Chirality (physics)?

W.F.Galway 00:19, 2 July 2007 (UTC)

Left handed means that, in the limit as the particle approaches c (or mass goes to zero), the spin and momentum are anti-parallel (helicity = -1). For right handed particles helicity = 1.--Michael C. Price talk 21:45, 16 February 2008 (UTC)

[edit] Color Charge in the Table

The color charge of each of these fields is fully specified by the representations. Quarks and antiquarks have color charge 4/3, whereas gluons have color charge 8. All other particles have zero color charge.

--Wikipedia article on color charge

These designations do not match what is listed in the table, despite the table's column header directing the reader to visit the color charge article. Some clarification is in order, as clearly the 1s and 3s currently in the table are designed to represent the particle belonging to the color singlet, or color triplet representations. However, as it stands I can easily see this being a possible source of confusion among non-physicists, who upon seeing that the electron has a color charge of "1" conclude that it does partake of strong force interactions, though with one-third the strength that quarks do. -- Balcerzak 03:02, 10 July 2007 (UTC)

[edit] More history

I believe the names Glashow, Salam, and Weinberg should appear somewhere in this article, since they received the 1979 Nobel prize for developing this theory. 194.94.224.254 15:54, 11 August 2007 (UTC)

[edit] Unifying the Standard Model with Gravity

Hey, I read this on Slashdot and thought you guys might enjoy. I didn't see it in the talk page and I certainly don't feel comfortable editing the main page with the information. Source:

http://www.telegraph.co.uk/core/Content/displayPrintable.jhtml?xml=/earth/2007/11/14/scisurf114.xml&site=30&page=0

Djdoobwah 02:05, 16 November 2007 (UTC)

[edit] For a few dollars more...

Hi

Can anyone give some more explaination in the caption to "Log plot of masses in the Standard Model". For instance what is the Y axis (Im assuming that there is one as things are spread out on it), and what are the boxes for (mass group maybe?).

Thanks

John

CaptinJohn (talk) 14:43, 22 November 2007 (UTC)

I'm only guessing here, but: x-axis is the mass, where the green boxes are used to indicate certain mass ranges (and hence the whole pic should not be considered four different plots as I initially did). X-Ranges (on black boxes) probably indicate the (un-)certainty to which the masses are known. The y-dimension seems to be simply used for a bit of grouping (meaning the y-extent of an entry has no meaning): Starting from 1st row with charged leptons (muon not labeled, neutrinos naturally not displayable on a log-plot), vectorbosons (again, photon missing due to m=0) with some miraculous four bars for W and Z, up-type quarks, down-type quarks and finally some bound states and the Higgs-vev in the last row. And considering that's just my interpretation and that I know the SM, I'd argue that the plot should be removed (or at least significantly improved, at the very least by labeling the axes)- no one not knowing the SM beforehand will even remotely understand it. --78.50.224.186 (talk) 02:52, 17 December 2007 (UTC)

[edit] Table of particle interactions

On picture Elementary particle interactions.svg, shouldn't be the W-boson interacting with itself? Thank you. --Irigi (talk) 14:57, 11 February 2008 (UTC)

Yes it should. All the electroweak bosons (A, Z, W+, W-) interact with each other; the W's also self-interact since they carry charge and isospin.--Michael C. Price talk 11:25, 14 February 2008 (UTC)
It is OK now, Stannered fixed it. Thank you for advice! --Irigi (talk) 08:33, 25 February 2008 (UTC)

[edit] Navigation template

I changed {{Quantum mechanics}} to {{Quantum field theory}}. Sorry about the earlier iterations.--Truthnlove (talk) 04:57, 2 March 2008 (UTC)

[edit] Intro

I don't know if the general public will understand "It unifies the electroweak theory and quantum chromodynamics into a structure denoted by the gauge groups SU(3)SU(2)U(1)." and so I believe it should be differed to somewhere in the middle of the article where the terminology can be explained.

I do think that it is important for the audience to understand that the Standard Model represents a compendium of scientific data since the beginning of modern science, which I believe should be stated somewhere in the introduction. --TriTertButoxy (talk) 06:21, 3 March 2008 (UTC)