Talk:Muon-catalyzed fusion

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Muon-catalyzed fusion[edit]

I'm a bit confused about the "unreferenced" tag that's been slapped on this article. There are a plethora of references, citations, and footnotes. Perhaps someone could help me out here and point to a specific example in the article of anything in need of further referencing. Puzzling--very puzzling, indeed--perhaps the "unreferenced" tag is is the work of some mischievious wikibot gone wild. Randyfurlong 20:59, 8 November 2006 (UTC)
This article is written at a very technical level and could use some dumbing-down, at least in the summary. --JD79 00:14, 15 October 2006 (UTC)
It's not just written at an excessively technical level; it's also extraordinarily verbose, with a large number of barely-relevant sidetracks. The main point is buried deep within the article, after about a page of physics blather. It should not take this much verbiage to say: "Muons are unstable subatomic particles created in particle accelerators. They are similar to electrons, but about 207 times more massive. When a muon is involved in chemical bonding between two atomic nuclei, the nuclei are consequently drawn 207 times closer together than they would be in a normal molecule. When the nuclei are this close together, the probability of nuclear fusion is greatly enhanced, to the point where a significant number of fusion events can happen at room temperature. Unfortunately, it is difficult to create large numbers of muons efficiently; moreover, their short lifetime of 2.2 microseconds means that a muon can only catalyze a few hundred nuclear fusion reactions before it decays away. These two factors limit muon-catalyzed fusion to a laboratory curiosity, although there is some speculation that an efficient muon source could someday lead to a useful room-temperature fusion reactor." Someone needs to go through all this verbiage and pick out the points that are actually relevant to the main point of the article.
The neutrality tag, however, is not appropriate. Muon-catalyzed fusion is not in any way associated with cold fusion "junk science" based on absorption of Hydrogen by Palladium. It is a real phenomenon which has been published and discussed in the physics community. I'm removing the NPOV tag.
Thanks for removing the inappropriate neutrality tag! Since I wrote most of that "physics blather" that you find so pointless and annoying, I'd be more than happy to winnow out any wheat from among the "extraordinarily verbose" chaff. The very fact that you apparently missed the most important point about muons sticking to the alpha "ash" a little too often is all the evidence I need that I'd better try harder to focus in on the essentials! Thanks (I think)! Randyfurlong 01:19, 7 November 2006 (UTC)

I like the level of the article... I found it informative without being excessively technical. A joy to read. (talk) 19:37, 9 February 2008 (UTC)

Copied from the cold fusion article:

Maybe add Jones and Rafelski to muon article[edit]

The introduction to the cold fusion article has a link to muon-catalyzed fusion. This article began by saying that Jones and Rafelski "initiated" muon-catalyzed fusion, but as you see from the link, they did not. Sakharov, Frank and Alvarez initiated it. (See the article here and Mallove, p. 108). So I removed Jones and Rafelski from the first paragraph. They did contribute to muon research, however. Perhaps someone should patch up the muon-catalyzed fusion article to include them. I am not familiar with their work, so I cannot do this. --JedRothwell 15:34, 13 April 2006 (UTC)

The first sentence[edit]

I would just like to point out that the first sentence is wrong. All the papers on muon catalized fusion that I have seen require tepuratures around 1000 K before significant amounts of fusion will occure. I realize that this is well below the tempuratures need for MFE but 1000 K is not room tempurature.
—The preceding unsigned comment was added by (talkcontribs) 23:38, 3 December 2006 (UTC).

I've altered the first sentence slightly in response to your (anonymous) suggestion. However, I know I've seen papers discussing cool fusion at truly cool temperatures, such as at liquid DT temperatures, where the rates of cool fusion are not at all shabby! See, for example, any of the Phys. Rev. Lett. articles by Steve Jones concerning experiments he and his group performed at LAMPF (the Los Alamos Meson Production Facility). Somewhat ironically, cool fusion needs to have temperatures that are below about 1 or 2 eV or so, corresponding to about 10,000K or 20,000K or so, because otherwise the Vesman resonances, which accelerate the formation of the muonic molecular ions, become useless, while hot thermonuclear fusion needs to have temperatures that are above at least 5 keV or more, corresponding to about 50,000,000K or more!

Randyfurlong 01:16, 6 December 2006 (UTC) Randyfurlong 01:17, 6 December 2006 (UTC)


It seems obvious that there is a divide between proponents of cold fusion and the general scientific community. Also obvious is that the CF article and its subsidiaries were edited largely by a small handful of proponents. So I added the same NPOV tag that exists on the main article.

Copyediting required[edit]

Seriously – we don't need all the particle symbols past the first use (perhaps once in each section). They clutter up the article and make it almost unreadable. –EdC 18:59, 11 January 2007 (UTC)

Holy footnotes batman![edit]

Wow, the footnotes on this article are incredible. Someone was up late at night working hard on those, thanks :) - JustinWick 19:05, 22 January 2007 (UTC)

Article bleeding from double blips: " here and " there[edit]

At "least" "some" of those "terms" "are" "established" "terms", and should "be marked" ''emphasis'' (emphasis), not "doubly blippy". Rursus 12:16, 9 March 2007 (UTC)

Muon decay energy[edit]

The article makes it sound like the energy produced by the muon's decay simply disappears. It doesn't (it can't!)-it too should become either thermal energy or a gamma ray. Right? Scythe33 (talk) 04:14, 10 January 2008 (UTC)

The muon decays into an electron, an electron-type antineutrino, and a muon-type neutrino, each having roughly one-third of the rest mass energy of the muon (about 105 MeV). The neutrinos escape without depositing any of their energy in the reactor, but the electron does give up about 35 MeV to the reactor. This is about the same amount of energy released by two muon-catalyzed fusions of deuterium and tritium, which is about 1% of the number of fusions catalyzed by the muon during its fleeting existence. So, yes, there is energy released into the reactor by each decaying muon, but no more than about 1% of the total energy released during each muon's catalyzing lifetime!Randyfurlong (talk) 18:16, 5 February 2008 (UTC)

Muon-catalysis of other fusion reactions?[edit]

Can muons increase the rate of other fusion reactions such as the aneutronic reaction p + 11B →3 4He + 8.7 MeV ? —Preceding unsigned comment added by Mwarren us (talkcontribs) 22:40, 14 May 2008 (UTC)

Cold fusion[edit]

Hi guys. I haven't yet formed an opinion on Cold fusion; my connection to the subject is that I just reviewed that article over at WP:GAN and passed it. There is kind of a late-breaking news story going on here; one of the fathers of hot fusion in Japan just demo'd his cold fusion experiment to a lot of people in the hall named in his honor in Japan, and it was fairly well-received. The story is picked up at, which is a news site that up to now hasn't been willing to touch "cold fusion news" with a ten-foot pole. So it might be prudent to back off any assertion in the lead of this article one way or the other on the subject of "cold fusion", and just stick to saying that that's something that muon-catalyzed fusion is not called, these days.

Btw, input over at Cold fusion is always welcome. - Dan Dank55 (talk)(mistakes) 18:04, 28 May 2008 (UTC)

I agree that this article shouldn't talk much about cold fusion, except for a brief statement. However, it would be appropriate to mention in the lede something along the lines of, "muon-catalyzed fusion is unrelated to cold fusion, a controversial subject considered pathological science by the mainstream scientific community." All of this is supported by the cold fusion page (so it would be easy to add a source), and would help to clear up confusion in regards to the link between these articles. (talk) 04:46, 3 October 2012 (UTC)
if the Widom-Larson theory is correct, what is happening in CF, if legit, is that a single proton hydrogen ion is being paired with a muon to produce a tight hydrogen atom that is effectively neutral in overall charge enough that it passes through the Coulumb barrier at much lower energy levels. So these two things could be related. — Preceding unsigned comment added by (talk) 15:04, 28 November 2012 (UTC)
Could say that μCF is described by the standard model, unlike CF. Fourtildas (talk) 22:16, 25 July 2013 (UTC)

Ordering the hydrogen in a solid?[edit]

Is there any record of attempts to use larger molecules in order to guide the process?

What about shooting muons down the length of a polymer such as (CF2CH2H3)n? Also, the stuff should be piezoelectric in the same manner as Polyvinylidene_fluoride too, which might be useful. Too bad it melts at such a low point... Zaphraud (talk) 08:36, 21 October 2008 (UTC)

The limiting factor is the alpha sticking process. Unless we can first solve this issue, attempts towards guiding the myon to faster d-t molecule provides little benefit. Nevertheless guiding is being though about, but not in the geometrical sense of the myon path, which is lost after the first reaction. rather guiding the d-t molecule formation. Roeschter (talk) 04:58, 3 January 2009 (UTC)


hi, my question is, if the sticking is a result of the fact, that a myons bohr-radius is possible on the inside of the atom-core... or if this another physical law... if this would be about the reasion of beeing "inside" tha atom -core that would mean, that a lighter negative electzrical particle (about 100 times heavier than an electron) could be used as a cold fusion catalyzer, not? greeting Q —Preceding unsigned comment added by (talk) 12:20, 20 November 2008 (UTC)

On Jackson's use of the term mu-meson[edit]

Someone added a comment about Jackson's use of the term "meson" being mistaken, since mesons are understood to be quark-antiquark pairs but a muon is a fundamental particle. However, Jackson's use of the term mu-meson was in accord with the usage of the term "meson" in 1957, when a "meson" was simply any particle with a mass intermediate between the mass of an electron and the mass of a proton. That's why I undid the edit that added the comment. Randyfurlong (talk) 03:58, 8 December 2008 (UTC)

reordering for the general reader[edit]

I moved the historical / sociological impact stuff to the top of the article, for the general reader interested in getting an overview of the topic. I left the detailed jargon-filled stuff at the bottom for people very interested who want to know all the technical details. --Enric Naval (talk) 05:26, 22 March 2009 (UTC)


it needs inline citations. i don't know how to place an Template:Inline section template (talk) 17:32, 2 June 2009 (UTC)

Leads should probably not have in-line citations or citations at all, because a lead should only briefly cover what is supported by the rest of the article. The article has plenty of in-line citations, but, if it's missing some, they should be applied. I disagree with placing such a template on this article based on the lead. If the lead makes claims that aren't supported by the rest of the article, they should either be removed, or the material should be added to the article body, with appropriate citations. --Abd (talk) 18:41, 2 June 2009 (UTC)
@, you should read the relevant guideline at WP:LEADCITE. This lead is not contentious, and it hasn't got material about living persons. Now, if there is a specific sentence that needs to be sourced because it looks to be wrong, then please point it out so it can be fixed in one way or other. --Enric Naval (talk) 21:15, 2 June 2009 (UTC)
I took out the sentence referring to the name being changed from "cold fusion." That's pretty much speculation, though we may be able to find some RS on it, though this may change. It is cold fusion, by the plain meanings of words, but it is also correct that "cold fusion" is colloquially used to refer to fusion without muons. (Some theories of cold fusion hypothesize that it is muon-catalyzed fusion that takes place in the metallic lattice, where, somehow, the muons become more efficient, so stray muons set up a chain reaction that goes on longer. However, there are many aspects of cold fusion that this doesn't account for, such as branching ratio, expected radiation, etc. If I've got it right, muon-catalyzed fusion does follow standard hot fusion branching ratio, which would mean that the reactions would generally produce neutrons. --Abd (talk) 22:36, 2 June 2009 (UTC)

I would like to know the source for each sentence in the lead so that I could verify it. I know nothing about the subject, and that's why I need to know source for every sentence, and not only 'contentious' ones, as i don't know what is contentious in this subject. (talk) 22:41, 2 June 2009 (UTC)

for example: it is believed that the poor energy balance will prevent it from ever becoming a practical power source uses weasel words. believed by whom? (talk) 22:43, 2 June 2009 (UTC)

Believed by John David Jackson in 1957, in the first section "A brief history" and in the fifth section "Some problems facing practical exploitation". Mind you, it lacks a source about his analysis still being valid and the 40% efficiency problem is also unsourced...
About citing very sentence in the lead, sorry to be harsh but WP:LEADCITE has nothing about sourcing every sentence in the lead because someone doesn't want to make the effort of reading the actial article... Mind you, I have no problem with challenging the sentences one by one, as soon as you explain the reasons for each one so other editors can have a go at fixing them. (and please notice that we are all volunteers and we only edit when we can! Some editors will only check this article every few days). --Enric Naval (talk) 23:05, 2 June 2009 (UTC)
thanks for clarification. anyhow, lead should connect two sentences to say that if part comes from same person/people. (talk) 08:04, 3 June 2009 (UTC)
Ok. I searched some sources, but, like other obscure physics topics, there are thousand jargon-filled papers with very specific experiments, and only a very few overviews with the generic information that the article needs , and most of those overviews are conference presentations or summaries at university courses. I finally found tAdvances in nuclear physics published in 1998, that says that energy efficency has not been achieved, but new discoveries could achieve it. I added one sentence at the end of the practical exploitation section, as a summary. Don't know how to fix the lead. --Enric Naval (talk) 20:33, 3 June 2009 (UTC)
Thanks! (talk) 21:36, 4 June 2009 (UTC)

I just changed the lead to try to make it a bit clearer. I removed mention of the life-time of muons, because that seems to have nothing to do with the energy limitations (instead the problem is that they stick, thus ending their usefulness much earlier than their average lifetime). I also added the part stating that this subject is unrelated to the more widely-known cold fusion phenomenon with palladium. (talk) 05:00, 3 October 2012 (UTC)


I agree with some of the criticism: the description of the process is buried several paragraphs down, I think it could be moved up to nearly the top. The suggested description ain't bad:

Muons are unstable subatomic particles created in particle accelerators. They are similar to electrons, but about 207 times more massive. If a muon replaces an electron in an atom's orbit, the nuclei are consequently drawn 207 times closer together than they would be in a normal molecule. When the nuclei are this close together, the probability of nuclear fusion is greatly enhanced, to the point where a significant number of fusion events can happen at room temperature. Unfortunately, it is difficult to create large numbers of muons efficiently; moreover, their short lifetime of 2.2 microseconds means that a muon can only catalyze a few hundred nuclear fusion reactions before it decays away. These two factors limit muon-catalyzed fusion to a laboratory curiosity, although there is some speculation that an efficient muon source could someday lead to a useful room-temperature fusion reactor.

--Feldercarb (talk) 21:00, 29 March 2010 (UTC)

As the article explains in detail, the short lifetime of 2.2 microseconds for muons is largely irrelevant to the question of how many nuclear fusion reactions a single muon can catalyze! Long before most muons decay, they have stopped catalyzing nuclear fusion reactions because they have stuck to helium "ash" from previously catalyzed nuclear fusion reactions. Without the alpha-sticking problem, each muon could easily catalyze myriads (tens of thousands) of deuterium-tritium nuclear fusion reactions in 2.2 microseconds because the muon-catalysis rate for deuterium-tritium nuclear fusions is on the order of 10^10 per second or faster! Myriads of deuterium-tritium nuclear fusions would be more than enough to create a positive energy balance, yielding net power. However, because of the alpha-sticking problem, each muon is only able to catalyze 200 or so deuterium-tritium nuclear fusions on average.Randyfurlong (talk) 07:16, 11 May 2010 (UTC)

I think the main point of this point is the intro is "too complicated". I don't think a discussion of alpha-sticking addresses the complication issue. Feldercarb (talk) 04:11, 11 August 2010 (UTC)

I agree that the intro may have been overly complicated and I think you've done a fine job of making it less so. However, it is simply not the case that the finite lifetime of the muon has anything whatsoever to do with limiting the number of fusions each muon can catalyze. That was one of the punchlines of Jackson's article. So, without further complicating the introduction with a digression into the "alpha-sticking" problem, and without sacrificing the relevant physics, I have touched up what you added. I think what you added makes a big improvement to the introduction! Thanks! Randyfurlong (talk) 21:09, 17 August 2010 (UTC)

Obvious missing points[edit]

1. Perhaps a note about number of Muons created per watt of input energy would be appropriate. Oh and someone tell me where we get free Tritium? I don't think "weasel words"(:it is believed that the poor energy balance will prevent it from ever becoming a practical power source) is appropriate for overfunded fusion research being labeled "successful" when it generates 100 watts of heat energy for 100,000 watts input. I'm not anti-Nuke in principle however it is bad engineering practice when the average U.S. Nuclear Energy Facility generates the same dollar amount of electricity as it takes to mothball it at end-of-life. 2. Where is the mechanism? [Some Conclusions ......the hyperfine resonant formation...] 'hyperfine' as a wiki reference makes no sense unless you plan on uddating hyperfine. How about College PChem, take the equation of the atom and change the electron mass to that of a muon and voila you get a molecule with closely spaced nuclei, calculate neutron or proton tunneling distance as longer than nucleus to nucleus distance, that is the theory behind Muon caltalyzed Cold Fusion or other Cold Fusion theories. 3. RE: 1H + 11B reaction: wikipedia article 'Aneutronic fusion'. Boron-10 neutron absorbtion cross section (~9000 barns) extends close to its atomic radius; the metallic radius in a metal-boride would be smaller. Nickel Boride is also an efficient Hydrogen activator like Palladium. I haven't found a table of proton absorbtion cross sections although the Aneutronic Fusion page might be a better reference.

Shjacks45 (talk) 01:11, 24 July 2010 (UTC)

Star Scientific Claims[edit]

As of November 2011, Star Scientific Ltd. (Australia) is claiming that they've 'solved' the problem of MCF and have built a 1MW working reactor. Not worth putting in article yet but worth mentioning here in the discussion section. Ref: — Preceding unsigned comment added by (talk) 18:38, 6 December 2011 (UTC)

As much as I would love to see muon-catalyzed fusion become something more than a mere laboratory curiosity, I've visited Star Scientific, Ltd.'s website and looked at the material they present there and I remain skeptical! They claim to have overcome the dreaded "alpha-sticking problem" that removes muons from active catalysis of further deuterium-deuterium and/or deuterium-tritium nuclear fusion reactions. However, their "solution" of the alpha-sticking problem appears to be such an abundant and cheap production of (negative) pions that decay into (negative) muons that the loss of a "few" muons due to alpha-sticking isn't really a problem any more! However, they don't bother to explain anywhere how they go about abundantly and cheaply producing their (negative) pions, beyond noting that traditionally pions have routinely been produced using rather powerful and expensive proton (or deuteron) particle accelerators! Perhaps they are using some secret and proprietary process, unknown to any other physicists in the world! If it looks too good to be true, sometimes it isn't! Big claims require bigger proof than they've provided so far! Randyfurlong (talk) 17:09, 31 January 2012 (UTC)

Fictitious novel "Catalysed Fsuion"[edit]

I have written a novel called "Catalysed Fusion" featuring muon catalysed fusion experiments at CERN and other goings on, published online at . Would it be useful to add a link to the book ?? Perhaps someone could check the book and decide. I am declaring my conflict of interest. Fx59022 (talk) 16:55, 26 April 2012 (UTC)

No, that would just be promotion. However if some independent person writes about that book in a reliable source, then another independent person could add text. Graeme Bartlett (talk) 21:32, 26 April 2012 (UTC)

Hi : I've been involved in editing other "Cold Fusion" articles, and came across a short story using Alvarez's version. I'll put them in an "In Culture" section. Alanf777 (talk) 20:16, 19 September 2012 (UTC)

Citation needed[edit]

Article currently reads in part muon-catalyzed d-t nuclear fusion (like most other types of nuclear fusion), produces far fewer harmful (and far less long-lived) radioactive wastes. This is a common speculation, but so far as I know no more than this, and possibly wishful thinking. The opposite speculation is that fusion will never be environmentally acceptable owing to the nuclear waste produced by neutron activation of the plasma facing material. Andrewa (talk) 06:41, 8 September 2012 (UTC)

Considering the material will be in place for 40 years at a time this is not an issue. Materials chosen will likely lead to particles with a very short half life, and thus the small amount of material (comparatively) is not a considerable issue. IRWolfie- (talk) 22:22, 25 July 2013 (UTC)

Hall effect?[edit]

The book: Negele, J. W.; Vogt, Erich (1998). Advances in nuclear physics (illustrated ed.). Springer. pp. 194–198. ISBN 0-306-45757-1 doesn't mention Hall effect anywhere, let alone p.194-198. — Preceding unsigned comment added by (talk) 22:08, 17 January 2013 (UTC)


I just added Category:Cold fusion. Sorry for not mentioning it when I did the edit. Anyone object to the added category?--Solomonfromfinland (talk) 05:32, 11 November 2013 (UTC)

The category is almost certainly unjustified. As generally understood, Muon-catalyzed fusion isn't 'cold fusion' in the Fleischmann & Pons sense - as this article makes clear. Per WP:BRD, I am going to remove the category again, and suggest that you don't restore it without first gaining consensus. AndyTheGrump (talk) 02:07, 18 November 2013 (UTC)
I agree that the category is inappropriate for the article. Headbomb {talk / contribs / physics / books} 05:12, 18 November 2013 (UTC)
I was thinking of cold fusion in the broad sense, that is, nuclear fusion at temperatures much lower than “hot fusion”. In that case the category would be appropriate.--Solomonfromfinland (talk) 05:17, 18 November 2013 (UTC)
You might want to consider starting a new category "room temperature fusion", and both this article as well as the cold fusion category (among other things) could go into it.Anythingyouwant (talk) 05:24, 18 November 2013 (UTC)
That category would be rather useless, as it would contain pretty much nothing. Headbomb {talk / contribs / physics / books} 06:01, 18 November 2013 (UTC)
Headbomb, perhaps User:Solomonfromfinland will agree with you, but I feel it's a legitimate suggestion. If you look at Category:cold fusion, it contains lots of biographic articles, so I don't see why a category about "room temperature fusion" couldn't have some as well (e.g. the folks who have been involved with muon-catalyzed fusion).Anythingyouwant (talk) 06:07, 18 November 2013 (UTC)
Would it be appropriate to restore this article to Category:Cold fusion, and write on said category page, something like, “Articles dealing with nuclear fusion at room temperature, or at least temperatures much lower than “hot fusion”.”? Also, does anyone object to me including a large number of biographies in said category?--Solomonfromfinland (talk) 06:13, 18 November 2013 (UTC)
According to this source, it might be better nowadays to call muon catalyzed fusion "cool fusion" to distinguish it from the fringe "cold fusion". I think the consensus here so far is that the cold fusion category should not host the legitimate and proven muon catalyzed fusion.Anythingyouwant (talk) 06:23, 18 November 2013 (UTC)