Talk:Meson

message: Why were spin and discovery date removed from the table?
no...there r spins and discovery dates in the table  — Preceding unsigned comment added by 117.206.76.247 (talk) 19:37, 28 August 2014 (UTC)
thread_title: Question 

message: How can the quark "makeup" contain a root - we are talking about particles, no?
Yep, but the type of particle is just a property of its state.  For something like an electron, there's really nothing else that matches the charge and the like, so you get a pure state.  But an up-antiup and a down-antidown are just different versions of the same thing, so real states are mixes of them, somewhat like molecular orbitals.
::Why is the subtraction then? --Kenny TM~ 12:55, Nov 25, 2004 (UTC)
:: That's a phase. If you have two possible values, that a quantum entity can have, you can superpose them with a different phase relative to each other. That's a bit hard to explain in an illustrative way but maybe this helps: If you want to use the formalism of quantum mechanics to calculate some property, and you know how to calculate the property for a basis state, then what should you do if you have a superposition of two basis states? Should you add the values, or subtract them, or what? Well, the phase and the \sqrt{2} shows you how to combine the individual values. So, we are not subtracting two quarks. The '-' is merely indicating that properties of the individual quark types have to be subtracted to get the value of the superposition. Simon A. 13:12, 25 Nov 2004 (UTC)
thread_title: Question 2

message: Is the "famously corrected" part correct?  I thought the original word
"mesotron" was from the Greek root meso- plus the ending from "neutron"
and "electron".  Was the actual "correction" more like pointing out that the suffix in "neutron" and "electron" is just -on, not -tron?
-- Anonymous, 04:40, 17 June 2005 (UTC)
replies: text: after a websearch, I think I was mistaken, and Heisenberg's comment was indeed about Greek morphology. meson would just be the Greek neuter form for "middle", meaning "the thing in the middle". The suffix -tron was mistakenly abstracted from the words electron and neutron which coincidentially both have a -tro- suffix. Baad 12:52, 31 October 2005 (UTC)
thread_title: Question 3

message: Should the names of the mesons be redirected here, to the list of mesons or to another article? -- Kjkolb 09:08, 19 December 2005 (UTC)
replies: text: The more important mesons ought to have standalone articles. I don't think it matters much if other mesons redirect to the list or here. The list has a link here at the top anyway. -- Xerxes 19:10, 19 December 2005 (UTC)
thread_title:  Names 

message: Perhaps a more simple article can be written? This uses too many words that are unknown to the reader, such as "quarks", "antiquarks" and "tetraquarks". If these are going to be in the article, then they should be explained. Scorpionman 23:02, 19 January 2006 (UTC)
replies: text: A reader unfamiliar with these terms is invited to click on the appropriate links. No individual wiki page can be expected to give the reader a complete science education. -- Xerxes 01:58, 20 January 2006 (UTC)
replies: text:  The introduction could be re-written to be clearer to reader unfamiliar with the topic and the body could stay complicated. I may try to fix it. -Ravedave (help name my baby) 17:59, 26 September 2006 (UTC)
thread_title:  Too complicated 

message: Ehi guys, it isn't true that all neutral mesons are eigenstates of C-parity, only those composed by the same quark-antiquark couple! For example either K0 and k0-bar aren't C-parity eigenstates...  —Preceding unsigned comment added by Leophys (talk • contribs) 14:17, 14 July 2010 (UTC)
thread_title:  C-parity 

message: I don't quite understand what u mean by integral. Doesn't that refer to the type of spin. Don't fermions have "half integer times h bar" integral spins as in (n/2)*(h bar) where n = 1,3,5..... In which case it would make more sense to say mesons are hadrons with integer integral "spins" or just integer "spin" ((n/2) * (h bar) where n = 2,4,6....
Alex
:Integral spin means just that: integers. 0, 1, 2, etc. -- Xerxes 18:03, 5 June 2006 (UTC)
thread_title:  integral spin 

message: How can a particle (like an up quark \mathrm{u}\,) and its antiparticle (an anti-up, \bar{\mathrm{u}}) coexist within a meson without annihilating each other? --HantaVirus 20:52, 9 August 2006 (UTC)
replies: text: They are tightly bound in the same potential and thus very close to each other, but not in exactly the same position. Particle physics is not my forte, but I would wager that the lifetime is related to the amount of time it takes for the two quarks to "find" each other. Eldereft 01:51, 27 September 2006 (UTC)
replies: text:  Yes, pretty much.  Note that the neutral pion (u + anti-u) only lives for 10^-16 seconds, so they find each other pretty fast. --Strait (talk) 17:43, 9 January 2009 (UTC)
thread_title:  <math>\mathrm{u}\,</math> + <math>\bar{\mathrm{u}}</math> 

message: Can someone work this information into the article?  it is beyond me how it might fit. -Ravedave (help name my baby) 18:02, 26 September 2006 (UTC)
thread_title:  article 

message: This article is way too complex even for an educated reader to understand.
For instance this sentence in the beginning of the article:
"The valence quarks may exist in a superposition of flavor states; for example, the neutral pion is neither an up-antiup pair nor a down-antidown pair, but an equal superposition of both."
'equal superposition of both'? In English please...
"Flavorless mesons are mesons whose flavor quantum numbers are all equal to zero."
You mean, 'are all zero'. Making things more complicated than necessary is a BAD thing.
Apparently the 'charge conjugation parity' page is written by an equally techno-babbling professor.
Stop making unreadable pages ffs.
Basically, anything below the heading 'flavorless mesons' is totally incomprehensible. This article needs a rewrite, BIGTIME. —The preceding unsigned comment was added by Crusty007 (talk • contribs) 23:06, 26 September 2006  (UTC)
:You have some valid points but there's no need to be rude about it.  The intro should be simplified, and I will work on it.  It may not be possible to keep the entire article simple; this is a rather technical subject, and except for the most basic details it can't be conveyed accurately without using technical concepts and terms. -- SCZenz 23:55, 26 September 2006 (UTC)
thread_title: way too complex

message: Lets work on the intro here. Below is my version, which I think turned out quite well. Do mesons bind protons and neutrons or is that just what they were predicted to do? -Ravedave (help name my baby) 05:39, 27 September 2006 (UTC)
thread_title:  Intro 

message: The new intro looks good to me.  To answer Ravedave's question... Yes, pions, to a good approximation, can be thought of as mediating the residual strong force—i.e., yes they cause the force between nucleons, as predicted by Yuakawa. Of course, that's not exactly what's going on, because really the quarks in the pions are interacting with the quarks in the nucleons, but it's close enough that pion exchange is a good model. -- SCZenz 21:26, 3 October 2006 (UTC)
thread_title:  Comments 

message: I'm confused as to how mesons can be bosons, and at the same time, be hadrons composed of quarks and antiquarks.  Quarks are fermions, no?  How can a meson be a fermion and a boson?  I thought these were mutually exclusive categories.  Please clarify, thanks.24.21.139.41 15:45, 12 May 2007 (UTC)
replies: text: Mesons are bosons because they have an even number of fermions in their makeup.24.21.139.41 00:31, 14 May 2007 (UTC)
replies: text: Bosons are any particle with an integer spin, so both force carriers and mesons have integer spin values, quarks on their own have a half spin as do leptons and baryons and so are all defined as fermions, this site might help: http://durpdg.dur.ac.uk/lbl/particleadventure/frameless/fermibos.html Murdochious (talk) 16:31, 15 February 2008 (UTC)
thread_title: Bosons?

message: It seems to me that the the sigma boson is worth mentioning, though it's more a broad resonance than a particle, because of its historical importance and since it is still the meson which "mediates" the nuclear force, if such a very rough interpretation of the nuclear force is made. I'm not an expert on this, so I guess someone else should write about it (If not, I will have to read this for example and still probably do some mistakes). Of course one should mention it's highly unstable and therefore not exactly a particle, and that mediation of nuclear force by mesons is only an approximate concept, etc. It should also be mentioned that the fact that the sigma is 0++ is responsible to the nuclear force being charge independent and to first approximation also spin independent; Correction to the latter (spin dependence) comes as far as I understand from mediating by the pion which is 0-+. Anyway I could also be wrong in some of these statesments, so somebody else please do the job.Dan Gluck 19:44, 3 June 2007 (UTC)
thread_title: Sigma boson

message: Two things at least are missing from this article and the result is an aimless feeling.
*  it says all mesons are unstable but doesn't say how they form
*  it says mesons were once thought to do the job that gluons do if I understand it correctly, but it doesn't say that nor does it say what mesons actually seem to do.  
This page should also mention the eightfold path and say what good that path is toward understanding mesons, or else point to the article on the eightfold path
4.249.198.64 12:56, 22 July 2007 (UTC)
thread_title:  needs work 

message: Please give input at Talk:Hadron#Hadron overhaul. Thanks. Headbomb {ταλκκοντριβς – WP Physics} 02:01, 24 January 2010 (UTC)
thread_title:  Hadron overhaul 

message: I'm a bit confused, in the chapter about classification/types of mesons, it says in the table that pseudovector mesons have a spin of zero, yet in the main article about pseudovector mesons it says:
In high energy physics, a pseudovector meson or axial vector meson is a meson with total spin 1...
Same goes for scalar mesons. I'm not a physicist, so... help anyone? 188.23.46.253 (talk) 09:14, 6 February 2010 (UTC)
thread_title:  Spin of pseudovector and scalar mesons 

message: I am curious as to the maximum "life expectancy" of mesons are; given that they are composed of a matter- antimatter pair.JeepAssembler (talk) 22:02, 22 February 2010 (UTC)
replies: text: There is a difference in B mesons and anti-B mesons in life expectancy, which is NOT listed at all, making the article incomplete. Some highly speculative and incomplete work I've personally viewed was considering vacuum metastability relationships between the decay rates. But, said work is still, at this time, far from complete.76.98.121.53 (talk) 03:45, 5 September 2011 (UTC)
thread_title:  Life Expectancy? 

message: The introduction of an article should contain the most basic and easy-to-understand material about the topic. It should not assume that the reader knows a bunch of technical terms.  A layperson coming to Wikipedia for information about mesons is likely to find the current article unhelpful because there's nothing here that's basic enough to be understood without spending all day studying particle physics.  If the article on electrons can do it, then so can this one.  A Wiki article isn't just a dumping ground for information; like all non-fiction, it's a teaching device, and it must keep in mind the needs of its likely audience.  As it is, the article is written as if it assumes that the reader is already highly knowledgeable in physics but just happens to be totally ignorant about mesons.  Since I'm not by any means a scientist, I'm unqualified to tamper with this article.  But basic information would be far more helpful to the layman than technical stats about spin, hadrons and C-parity.  Where would you find a meson?  How big is it?  What does it do?  Why does it matter?  Simple questions like these should be answered in simple English before getting into the jargon. Then the readers have a simple base from which to learn the technical stuff in the rest of the article, if they so choose. Nine9s (talk) 06:49, 6 April 2010 (UTC)
replies: text: Okay, I've added a front end for the general reader. See what you think. SBHarris 00:11, 15 October 2010 (UTC)
thread_title:  The Introduction is too technical 

message: Why are the  not classified as flavorful mesons? Up and down are flavors, are they not? --Michael C. Price talk 10:07, 14 October 2010 (UTC)
thread_title: Flavorful pions

message: The 4 T-mesons at the lower right should be anti-T's have opposite charges, otherwise the charges are all wrong.  --Michael C. Price talk 11:36, 14 October 2010 (UTC)
replies: text: Done. --Michael C. Price talk 08:48, 15 October 2010 (UTC)
thread_title: Flavorful mesons table

message: Headbomb,
Why do we need to mention the pronunciation of ħ?  Wouldn't most readers know & most of the few who don't be able to click on the link to find out?  Who'd be able to read through this and make some sense of it but never have heard of ħ? 
JIMp talk·cont 01:21, 23 October 2010 (UTC)
replies: text: I've deleted this. JIMp talk·cont 08:28, 16 June 2013 (UTC)
thread_title:  Pronunciation of ħ 

message: From what little I understand, the Eta meson's quark makeup is in a superposition of up-antiup/down-antidown/strange-antistrange. But wouldn't we cause the superposition to collapse when we measure its mass? After all, ups and downs have less mass than stranges do. When we measure the mass of an Eta meson, shouldn't the superposition collapse into either a pi-zero or whatever it is you call a strange-antistrange meson? Curious George 334905 (talk) 23:27, 16 July 2011 (UTC)
replies: text: No, that doesn't happen because the quark content is responsible for just a minor component of the meson's mass. Most of the mass is created dynamically by the interaction of the quarks with a variety of gauge bosons some of which mix strange quarks with the up and down quarks. That effect is negligible in most situations but the eta meson is an important case where it isn't. Dauto (talk) 02:06, 17 July 2011 (UTC)

text: What I mean is that when the quarks exchange W-bosons they turn into each other. That contributes an off diagonal component to the meson mass matrix that allows for mesons with mixed quark composition. That effect is negligible compared to the c,b,t quark masses and that's why the c-c-bar, b-b-bar and unobserved t-t-bar mesons do not mix. But that effect is not negligible compared to the u-u-bar, d-d-bar, and s-s-bar which will mix forming the pi-zero, eta, and eta' mesons. Dauto (talk) 18:28, 19 July 2011 (UTC)
replies: text: BTW Dauto, do you have a reference for that? Some book passage or some journal? I've been dying to understand that quark mixing in mesons since a few years now and I've never been able to find something about it. Would be quite useful for my master's degree. Headbomb {talk / contribs / physics / books} 19:32, 19 July 2011 (UTC)
thread_title:  Eta meson quark content? 	 

message: Someone vandalized the list at the bottom of the page, but I am having difficulty figuring out how (I can't find where in the code it is). Will someone more knowledgeable than I please fix it?  — Preceding unsigned comment added by 192.5.109.34 (talk) 10:14, 2 May 2012 (UTC)
thread_title: Vandalism

message: It states that a meson has a redius of a femtometer, 2/3 that of a proton or neutron. However, the radius of a proton is about 0.85 femtometers.76.10.168.53 (talk) 23:00, 1 June 2014 (UTC)
replies: text: Good pick up. It has a DIAMETER of about a femtometer. SBHarris 01:09, 29 August 2014 (UTC)
replies: text: Either way, I'd want a source for that. I suspect it's an order-of-magnitude thing, where radius/diameter isn't super important. But it should be backed by a source. Headbomb {talk / contribs / physics / books} 06:41, 29 August 2014 (UTC)
thread_title:  Error in first paragraph 

message: I've been working on neutron magnetic moment and have been contemplating how this anomalous magnetic moment was understood over the thirty years ca. 1934-1964.  I have some sources (Pais Inward Bound; Brown/Rechenberg Origin of the Concept of Nuclear Forces; Bjorken and Drell Rel. QM (Drell obviously worked really hard on this problem)), but the theory people were using to attack the problem of the magnetic moments is a bit beyond me (or, perhaps, would require more work than I am willing to do...).  I am wondering if perhaps some of you meson experts might attempt a brief paragraph or two on explaining the theoretical strategy and describing how poorly the theory worked for these magnetic moments.  Pais p. 483 calls these theory "a flop".  My initial thought was to start with the QED explanations for the anomalous magnetic moment of the electron which worked so well, and carry this strategy over to the pions 
and the nucleons; this is roughly what happened historically.  At the same time, I note that this particular problem was an important one to the development of vector meson theory of nuclear interactions, so this article could perhaps benefit from such a section.  (If there are no volunteers, I will eventually do what I can...)  Bdushaw (talk) 12:57, 27 February 2015 (UTC)
replies: text: Per my threat above, I've developed the section Neutron magnetic moment#Thirty years in the theoretical wilderness.  Rather outside my comfort range, so reviews/corrections welcome.  One wonders how people explained these thirty years of misguided theory after the quark model came on the scene.  Bdushaw (talk) 09:14, 16 March 2015 (UTC)
replies: text: The quark model does not seem a very guided theory either considering that the magnetic moments of undetectable free quarks cannot be measured.--86.125.161.205 (talk) 21:15, 17 March 2015 (UTC)
thread_title:  Attempts at understanding anomalous nucleon magnetic moments through vector meson theory 

message: Two issues: 1. it would, imho, be much better to describe mesons as composite bosons in the lede. Otherwise, people who do not understand that bosons can be elementary particles or may be composite will be quite confused, since this 'subject' is 'about' elementary particles (ie particle physics). 2. I came to this article expecting at least something about the colors of the quark pairs. There is nothing! Wow. Even the article on pions has no explanation why the pion in the diagram is blue-yellow. Are mesons neutral colored? If so, are there any differences between Red-Cyan, Green-Magenta and Blue-Yellow mesons?? (Or do they exist as superpositions of the three color-anticolor charges?). Same question if they possess a net color charge. This SHOULD be discussed! My two cents. Another comment I have is the emphasis on flavor. My ignorant impression is that flavor is simply a different way to characterize the type of quark - that is: the strange and only the strange quark has strange flavor, the charm and only the charm quark has charm flavor, etc., etc. The reason why this double bookkeeping is done should be explained (I assume there is a reason, lol). Probably this isn't the place for that, but I note that generally in Wikipedia when color is discussed, flavor isn't, and vice versa; which is inexplicable to me.Abitslow (talk) 22:02, 26 March 2015 (UTC)
replies: text: I forgot to consider a third possibility: that while every meson is neutral colored, the quark-antiquark pairs in superposition each have a net color.  — Preceding unsigned comment added by Abitslow (talk • contribs) 22:09, 26 March 2015 (UTC)
thread_title:  Clarifications needed 2015 

message: The article states that the word meson is pronounced as ˈmiːzɒn/ or /ˈmɛzɒn/. Other12 Google results suggest /ˈmiːsɒn/ is a valid pronunciation as well. Is that wrong?
Wilhelmtell (talk) 23:38, 29 December 2015 (UTC)
thread_title:  Pronunciation of Meson 

message: In the 3rd paragraph of the History section, this sentence now appears:  Some of those mesons had about the same mass as the already-known meson, yet seemed to decay into it, leading physicist Robert Marshak to hypothesize in 1947 that it was actually a new and different meson. (Emphasis added.) I suppose the "already-known meson" is what is now called the muon; but in that era, the name "meson" meant the muon, which is no longer considered to be a meson. Improved wording would reduce the potential for misunderstanding. In my undergraduate days, I passed 2 years of physics, but I don't know this topic well enough to do the editing. Someone else should do it. Oaklandguy (talk) 22:21, 23 November 2019 (UTC)
replies: text: PS: I happened to notice that pions (current name) decay (at least for the charged pions, often) into a muon plus a neutrino of some kind. (See List of mesons.) This supports my supposition. I still want someone else to do the actual edit. Oaklandguy (talk) 00:19, 24 November 2019 (UTC)
thread_title:  In the History section, probable glitch in nomenclature; needs rewording 

message: I think there is an error in the history part: "The pion (as a virtual particle) is the primary force carrier for the nuclear force in atomic nuclei." As far as I know, nowadays it is known that the gluon and not the pion is the virtual particle of the strong interaction. maybe that should be mentioned... — Preceding unsigned comment added by 181.167.33.8 (talk • contribs) 
: This comment is deeply misguided. Gluons act inside hadrons and do not leave them to bind them into nuclei.  You should not "know" that. Residual strong interactions are strong. No mention of gluons could be salutary here. Cuzkatzimhut (talk) 13:07, 27 March 2021 (UTC)
thread_title: Random comments

message: Reworked inline citations to link directly to the full citations at the bottom of the article. Please review and remove the citation style cleanup needed flag if the rework is acceptable.
Extemporalist (talk) 23:43, 11 October 2021 (UTC)
thread_title: Citation Style Reworked

message: How is this article has been criticized, argued, etc. for literally over a decade yet has not been subjected to the most basic rule of Wikipedia "PROVIDE CITATIONS"? 2600:1700:8A90:ECF0:41E8:1437:ACA:73B (talk) 22:20, 29 July 2022 (UTC)
replies: text: The article, on the whole, has citations. If there is a particular section that you feel is weak in sourcing, please indicate which one. —C.Fred (talk) 22:21, 29 July 2022 (UTC)

text: There is no requirement that a citation have a link. Not every valid reference exists online. However, looking at the references, if there aren't links to the sources, there are links with the ISBN. Your other comment about TV shows demonstrate a basic lack of understanding of the Manual of Style. Based on that, as well as my review of the citations, I see no need for any action to be taken here (other than one reference that needs fixed). —C.Fred (talk) 13:20, 30 July 2022 (UTC)
thread_title:  PLEASE FIX MY REQUEST FOR CITATIONS