Talk:Higgs boson

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Ambiguous first sentence[edit]

The first sentence reads "The Higgs boson [...], whose discovery was announced [...], and confirmed likely to be a Higgs boson in March 2013." How can it be discovered and not discovered at the same time? Should it say that some *new particle* was discovered that is likely to be the Higgs boson but we just don't know yet? rkaup (talk) 05:03, 8 March 2014 (UTC)

You're right. This is exactly the point. A new particle is discovered that can be the Higgs boson but we cannot certify that it is really the Higgs Boson without the help of the next generation of particle accelarators. They are needed to measure the "self couplings" of this particle, that is to say the possibility of a single "Higgs boson" to decay into 2 or more similar particles, which is the main characteristic of the Higgs boson that is not shared by other particles. Fred1810 (talk) 20:55, 14 March 2014 (UTC)
I fully agree that the first sentence is confusing. The editor who made it this way wanted to stress that the discovery of a new particle - widely assumed to be the Higgs boson - was announced on July 4, 2012, but it was only on March 2013 that the measurement of some properties of this new particle confirmed that it does indeed behave as expected from the Higgs boson. In my opinion, now that it is accepted that the particle discovered in 2012 is a Higgs boson, and a Nobel prize has been awarded to Englert and Higgs for its prediction, we don't need to make the opening sentence so heavy. We can just write that the particle was discovered on July 4 2012, then the timeline of the various announcements is described in full detail in the second paragraph of the lead. Cheers, Ptrslv72 (talk) 17:07, 4 April 2014 (UTC)
I would go as far as to say that the discovery and/or announcement do not need to be mentioned in the first paragraph at all. In terms of modern news cycles this is now ancient history. We should probably go towards a lede that is more inline with that of other fundamental particles and leave the date of discovery etc. to a later paragraph summarizing the history. (see e.g. electron or quark both FAs). This also leaves more room for nuance regarding the current status.
The first paragraph should focus on answering the questions: "What is a Higgs boson?" and "Why is it important?" in an so accessible way possible.TR 09:18, 17 April 2014 (UTC)
Fine for me. Cheers, Ptrslv72 (talk) 13:23, 17 April 2014 (UTC)

suggestion for first to paragraphs[edit]

Procrastinating on writing an actual paper I had a go at the first two paragraphs:

The Higgs boson or Higgs particle is an elementary particle in the Standard Model of Partical physics. Its main relevance is that it is the smallest possible excitation of the Higgs field;[1][2] A field that unlike the more familiar electromagnetic field cannot be "turned off", but instead takes a constant value almost everywhere. Its existence explains why some fundamental particles have mass when the symmetries controlling their interactions should require them to be massless, and why the weak force has a much shorter range than the electromagnetic force.
Despite being present everywhere, the existence of the Higgs field has been very hard to confirm, because it is extremely hard to create excitations (i.e. Higgs particles). The search for this elusive particle has taken more than 40 years and led to the construction of one of the world's most expensive and complex experimental facilities to date, the Large Hadron Collider,[3] able to create Higgs bosons and other particles for observation and study. On 4 July 2012, it was announced that a previously unknown particle with a mass between 125 and 127 GeV/c2 (134.2 and 136.3 amu) had been detected; physicists suspected at the time that it was the Higgs boson.[4][5][6] By March 2013, the particle had been proven to behave, interact and decay in many of the ways predicted by the Standard Model, and was also tentatively confirmed to have positive parity and zero spin,[7] two fundamental attributes of a Higgs boson. This appears to be the first elementary scalar particle discovered in nature.[8] More data is needed to know if the discovered particle exactly matches the predictions of the Standard Model, or whether, as predicted by some theories, multiple Higgs bosons exist.[9]

Not entirely satisfied with the result though. So nice parts are that it tones down on all the Higgs hype that was a bit over present and make some attempt to give an idea what this Higgs field is. Maybe somebody can bend this in something useful?TR 12:09, 28 May 2014 (UTC)


Could the first paragraph be changed to define or describe the physical qualities of the Higgs boson, as per the article for the other bosons? As it is now, the first 3 paragraphs are able the history of the search for it, which I feel should come after its definition. Ashmoo (talk) 16:00, 7 August 2014 (UTC)

References
  1. ^ Onyisi, P. (23 October 2012). "Higgs boson FAQ". University of Texas ATLAS group. Retrieved 2013-01-08. 
  2. ^ Strassler, M. (12 October 2012). "The Higgs FAQ 2.0". ProfMattStrassler.com. Retrieved 2013-01-08. [Q] Why do particle physicists care so much about the Higgs particle?
    [A] Well, actually, they don’t. What they really care about is the Higgs field, because it is so important. [emphasis in original]
     
  3. ^ Strassler, M. (8 October 2011). "The Known Particles – If The Higgs Field Were Zero". ProfMattStrassler.com. Retrieved 13 November 2012. The Higgs field: so important it merited an entire experimental facility, the Large Hadron Collider, dedicated to understanding it. 
  4. ^ Biever, C. (6 July 2012). "It's a boson! But we need to know if it's the Higgs". New Scientist. Retrieved 2013-01-09. 'As a layman, I would say, I think we have it,' said Rolf-Dieter Heuer, director general of CERN at Wednesday's seminar announcing the results of the search for the Higgs boson. But when pressed by journalists afterwards on what exactly 'it' was, things got more complicated. 'We have discovered a boson – now we have to find out what boson it is'
    Q: 'If we don't know the new particle is a Higgs, what do we know about it?' We know it is some kind of boson, says Vivek Sharma of CMS [...]
    Q: 'are the CERN scientists just being too cautious? What would be enough evidence to call it a Higgs boson?' As there could be many different kinds of Higgs bosons, there's no straight answer.
    [emphasis in original]
     [dead link]
  5. ^ Cite error: The named reference ScienceNews was invoked but never defined (see the help page).
  6. ^ Del Rosso, A. (19 November 2012). "Higgs: The beginning of the exploration". CERN Bulletin (47–48). Retrieved 2013-01-09. Even in the most specialized circles, the new particle discovered in July is not yet being called the “Higgs boson". Physicists still hesitate to call it that before they have determined that its properties fit with those the Higgs theory predicts the Higgs boson has. 
  7. ^ Cite error: The named reference CERN_March_2013 was invoked but never defined (see the help page).
  8. ^ Naik, G. (14 March 2013). "New Data Boosts Case for Higgs Boson Find". The Wall Street Journal. Retrieved 2013-03-15. 'We've never seen an elementary particle with spin zero,' said Tony Weidberg, a particle physicist at the University of Oxford who is also involved in the CERN experiments. 
  9. ^ Cite error: The named reference Huffington_14_March_2013 was invoked but never defined (see the help page).

Problems with the first paragraphs[edit]

The opening paragraphs need a lot of clarification, restructuring, factual accuracy clean-up, and probably a complete rewrite. Here's an line-by-line discussion of problems.

The Higgs boson or Higgs particle is an elementary particle in the Standard Model of Particle physics.

This is misleading. The standard model does predict a higgs boson which is consistent with the boson that was discovered in 2012, but this is not the definition or the limit to higgs bosons. There are ideas that should be separated: the standard model higgs boson, and higgs bosons in general. The first is a particle of the standard model and the simplest instance of a higgs boson. The second is a feature of a more general class of possible higgs mechanisms. For instance, if supersymmetry is found we should expect a total of five higgs particles.

Its main relevance is that it is the smallest possible excitation of the Higgs field

The second sentence should be reserved for further defining the higgs, rather than entering into a strange discussion of it’s “relevance” to some unstated topic as if this were a justification of funding. This appears to be an attempt to introduce its importance, which cannot be understated since it is the centerpiece of the standard model. It’s importance should be listed as follows:

  • First, the higgs boson discovery is proof that the higgs mechanism exists in nature.
  • Second, the higgs mechanism endows mass to all other known fundamental particles. This happens to be necessary for life in the universe to be possible.
  • Third, the evidence of the higgs mechanism resolves a long standing mystery of how the W and Z bosons acquire large masses when Electroweak symmetry in the absence of the higgs mechanism would require them to be massless.
  • Fourth, the discovery completes the standard model by resolves major structural inconsistencies, including the case of WW scattering where the standard model in the absence of a higgs mechanism predicts nonsensical probabilities greater than 1.
  • Fifth, the precise value of the higgs mass has major implications for the stability of the vacuum and the ultimate future of the universe.
  • Sixth, It’s the first fundamental scalar in nature.
  • Seventh, it’s a gateway to detecting other particles beyond the standard model.
  • Eighth, the higgs discovery brings the Hierarchy problem into clear focus as a mystery of the origin of the higgs boson mass. This sets the Hierarchy problem as one of the most important unsolved mysteries in physics.
Most of these points are factually inaccurate.
  • The Higgs boson is not proof that the Higgs mechanism exists in Nature. That has been beyond doubt since essentially LEP. The Higgs boson (once its properties are established) is proof that the Higgs field exists and causes the Higgs mechanism.
  • The Higgs mechanism is only responsible for electroweak symmetry breaking. Mass generation for fermions is a different mechanism (that is also made possible by the existence of a non-zero Higgs field).
  • The standard model would break electroweak symmetry with or without the Higgs (due to the occurrence of mesons). However, W and Z would be a lot lighter without a Higgs field.
  • The sixth point is already mentioned in the lede.
  • The seventh point is essentially BS.
TR 08:56, 16 September 2014 (UTC)

– a field that unlike the more familiar electromagnetic field cannot be "turned off",

This is totally confusing without an explanation of what “turned off” means and makes asserts that the reader has some sort of familiarity with electromagnetism. It also misses the grand picture of a field with non-zero value filling all of space.

The second part of that sentence clarifies what "cannot be turned off" means. Electric and magnetic fields are by far the most likely examples of fields that people will have encountered. Without such a comparison we will lose most of the audience the moment we start talking about fields.TR 09:15, 16 September 2014 (UTC)

but instead takes a constant value almost everywhere.

Why almost? It’s everywhere within our observable universe. This is hinting the higgs field’s non-zero VEV but never actually stating it. The non-zero VEV is only parenthetically mentioned once deep within the technical discussion even though this is the central feature of the higgs mechanism and evidence for it is a profound revelation discovery about the nature of the vacuum we inhabit. A main goal of the article should be communicating that we are swimming in a universal higgs field that has a non-zero value even in empty space, and that this field is required for life to be possible. Also, this is now a run-on sentence.

"Almost" because it is not constant whenever a Higgs boson is created. (Which happens all the time, be it for very short periods.) Also, this is about as accessible an explanation of what "having a non zero VEV", means.TR 09:08, 16 September 2014 (UTC)

The presence of this field explains why some fundamental particles have mass while the symmetries controlling their interactions should require them to be massless

This should explicitly mention the W and Z bosons rather than be vague. Shockingly, no where in the first paragraph on the higgs boson is there mention that the higgs endows mass to all other fundamental particles.

In my opinion "some" should simply be dropped from that sentence. (The Higgs field is responsible for the masses of all fundamental particles.) However, I have been overruled on that point in the past. I think the argument was that the sentence could then suggest that all fundamental particles have mass.TR 09:08, 16 September 2014 (UTC)
Also, note that the clause following this sentence gives an explicit statement of what it means that the W and Z bosons have mass. (Namely that the weak force has a short range.) That statement is a lot more accessible (and physically meaningful) then the rather abstract statement that W and Z have mass.TR 09:19, 16 September 2014 (UTC)

Despite being present everywhere, the existence of the Higgs field has been very hard to confirm, because it is extremely hard to create excitations (i.e. Higgs particles).

The explanation here is false. If that were the difficulty, LEP or the Tevatron would have discovered the higgs decades ago. The main difficulty is that almost all the higgs decay products look nearly identical to background noise products of particle collisions produced billions of times more often than the higgs.

I think "is hard to excite" is a pretty good summary of "is produced billions of times less than other particles in similar collisions.TR 09:27, 16 September 2014 (UTC)

The search for this elusive particle has taken more than 40 years and led to the construction of one of the world's most expensive and complex experimental facilities to date, the Large Hadron Collider,[8] able to create Higgs bosons and other particles for observation and study.

First, although expense is a concern it’s pretty impolite to the experimentalists to highlight the project cost first, especially while presenting such a poor explanation of the motivation. It gives the reader the impression that scientists are throwing away huge amounts of their tax money for some trivial esoteric reason. A better statement would be "..the world's largest, most ambitious, most complex, and most expensive experimental facilities...". Second, the LHC's defining feature is not that it’s able to create higgs bosons, but to discover the higgs boson anywhere within the allowed mass range imposed by precision electroweak measurements done at LEP. Both LEP and the Tevatron created higgs bosons but were unable to discover them. (Also, the LHC's ability to create other particles is a little off topic.) A better statement would be "the Large Hadron Collider, able to create Higgs bosons in sufficient quantity to be discovered and studied."

By March 2013, the particle had been proven to behave, interact and decay in many of the ways predicted by the Standard Model, and was also tentatively confirmed to have positive parity and zero spin,[1] two fundamental attributes of a Higgs boson.

It should be emphasized here that we have not proven it to be the standard model higgs boson, only that it is a higgs boson consistent with the standard model higgs boson. We absolutely have not proven that it is the standard model higgs boson not something subtly different. In particular, it is not at all clear that the higgs boson discovered decays precisely the rate predicted by the standard model. Pulu (talk) 07:27, 16 September 2014 (UTC)

Yes, and that emphasis is given just two sentences later in the same paragraph.TR 09:27, 16 September 2014 (UTC)
Such a proof is impossible. All known particles could be something slightly different, but we still call the muon "muon" and not "muon-like particle". And its decay channels are still under investigation as well because they could deviate from the SM. There is no fundamental difference, the measurements for the Higgs are just less precise (in comparison to the muon, by orders of magnitude). The "Higgs-like" particle is so Higgs-like everyone treats it as the SM particle now. And there won't be a magic moment where suddenly measurements will say "it is exactly the Higgs!" - just more and more precise confirmations (or new physics). --mfb (talk) 21:32, 17 September 2014 (UTC)

Statement of the Higgs Mass[edit]

I am reverting a change made to the article where the best estimates of the higgs boson mass from ATLAS and CMS were replaced by a single out of date figure listed by the PDG. The higgs mass should be kept up to date and as precise as possible since many theories are extremely sensitive to the exact value of the mass. The higgs mass is known from experiments done at the ATLAS and CMS experiments, so their latest results should be considered the most authoritative. It may be appropriate to list a single mass instead of two if and when a paper is published which combines the measured masses into a single mass with better resolution than either estimate individually. The mass listed on the 2014 PDG does not achieve this since the mass listed uses CMS and ATLAS masses published in 2013--which excludes a large section of the data (only 12 fb^-1 of 8 TeV collisions from CMS) and do not use the most modern methods for reducing the systematic uncertainty. Pulu (talk) 16:44, 15 September 2014 (UTC)

I disagree. Having two different masses in the infobox of an encyclopedia is confusing for the general reader, who will be dumbfounded how a single particle can have two different masses. (or worse can be led to believe that two particles have been found). Your arguments for keeping the mass "as up to date as possible" are irrelevant for an encyclopedia. Furthermore, the PDG value has the advantage of coming from a secondary source. It has long been a best practice to list the PDG values for particle data, even if more recent results are available, precisely for that reason. TR 20:59, 15 September 2014 (UTC)
I can understand the desire to have a simple statement of the higgs mass in the infobox. Unfortunately, this particle is quite new and the state of human knowledge currently consists of two separate estimates. The PDG, which usually serves as a grand repository of establish knowledge, is unable to reflect the current, rapidly changing state of knowledge as rapidly the experiments' publications and subsequently wikipedia, so this best practice will fail the readers. (As for keeping wikipedia up to date, that is absolutely relevant, extremely important, and most of the point of having a digital encyclopedia.) There is also physics motivation for listing as precise a value of the higgs mass as possible. Many model parameters are exponentially dependent on the higgs mass, while only logarithmically dependent on the masses of every other particle in nature. One of the central goals of particle physics is to establish the higgs boson mass as precisely as possible, and the article should reflect this. If we are to list a single value, I agree that we should list the PDG value. However this should be accompanied by a listing of the true state of knowledge in the article. Therefore I propose we change the infobox back to the PDG value for simplicity and add discussion within the article in which this and future up-to-date estimates of the higgs boson mass are presented for those interested. Is this agreeable? Pulu (talk) 04:07, 16 September 2014 (UTC)
Yes, that we would be a suitable approach IMHO.TR 08:40, 16 September 2014 (UTC)
Per WP:CALC, I've added an up-to-date combined CMS-ATLAS estimate; it is 125.17 ±0.26 (stat) +.16
-.15
 
 (sys). Someone should check the calculations, since the asymmetry in the CMS error margins implies a skewed confidence distribution, and I'm not sure the formulas for combining heteroskedastic sets of estimates are the same when that's the case. NeonMerlin 12:26, 3 October 2014 (UTC)
How did you get the ±0.26? Combining the CMS value with this uncertainty with the ATLAS value with a comparable uncertainty should lead to a smaller value. The combination of the systematic uncertainty is non-trivial as those can be correlated. --mfb (talk) 12:46, 7 October 2014 (UTC)
Agree with Mfb. The combination of ATLAS and CMS results is a non-trivial task that requires understanding of how the systematic uncertainties are correlated. It has to be performed by the collaborations and definitely does not fall under WP:CALC, which refers to routine calculations. Cheers Ptrslv72 (talk) 23:04, 12 October 2014 (UTC)
I removed the homemade combination, but I did not act on Pulu's last suggestion (which FWIW I find good). On a more general note, the article is hypertrophic, and somebody (not me) should undertake the heroic task of slimming it down. To start with, I would get rid of the useless "technical aspects" section at the end, but there is much more fat to cut... Cheers, Ptrslv72 (talk) 23:18, 12 October 2014 (UTC)

Are scientists certain?[edit]

So, I read in the article: As of 2013, scientists are virtually certain that they have proved the Higgs boson exists. I cannot find this in sources, so I tried to put a citation need. While editing, this notice appeared: Read this before editing! 1) Be very careful not to suggest the discovery is finished. Do not say the Higgs boson has been definitively discovered or confirmed. I guess that at least one of the two statements should be corrected or at least modified. It is hard for me to grasp the difference between "virtually certain" and "definitively discovered". This is a matter of subtle philosophy; the latter makes sense for everyone (except solypsists, perhaps;) but the meaning of "virtually certain" is extremely vague. (By the way, I would bet that the particle is an Higgs boson, but I suspect that noone is virtually certain, so far)! Best.78.15.203.91 (talk) 20:19, 19 September 2014 (UTC)

My personal experience as particle physicist is not a reliable source, but experimental physicists working on that consider the SM-like Higgs boson as found beyond reasonable doubt (there is never 100% certainty). Now the research is about "is there something else? More Higgs-like particles, or something that gives the SM Higgs boson a deviation from the SM prediction?" The official statements are more careful - the media always exaggerate news, that has to be compensated somehow. --mfb (talk) 12:34, 7 October 2014 (UTC)

CERN Scientists Report Discovery is Not Higgs Boson [ http://www.dumb-out.net/cern-scientists-report-discovery-higgs-boson/11406 ][edit]

Time to gut out all the hype and nonsense in this article. They have NOT found the Higgs boson. 50.141.70.3 (talk) 19:10, 8 November 2014 (UTC)

We go by scientific consensus, not a single paper, also that article is not accurate. Bhny (talk) 19:12, 11 November 2014 (UTC)
That is the personal opinion of Mads Toudal Frandsen, and apparently no one follows him. He also does not have a model that can explain all the measurements done so far (or he did not share it, which is the same thing). --mfb (talk) 00:24, 13 November 2014 (UTC)

I just saw this - important to the article?[edit]

I just found this in the news - should it be in the article, or at least an external link? Bubba73 You talkin' to me? 00:32, 9 November 2014 (UTC)

Too early, I'd say. Yet I think it should be considered as a caution to those editors who have chosen to edit the article to strongly suggesting that the (or even a) Higgs particle has been definitively found, based on current sources. When (and if) more solid information emerges, we can include information about the possibility that the particle observed at CERN is not a Higgs. —Quondum 15:07, 9 November 2014 (UTC)
Yea, every article I have read seems to be written by amateurs. Most of them have very poor grammar and make some false statements (i.e. one articles states that it is the CERN scientists which are saying they were wrong). Approach these articles with skepticism. — Preceding unsigned comment added by 2607:FCC8:A6C1:D000:B0A7:DAD7:160:5179 (talk) 04:39, 10 November 2014 (UTC)
The first sentence alone contains several inaccuracies. Anyway, due to the nature of the scientific method, there will always be an infinite number of alternative hypotheses that have not been ruled out by experiment. Come practice is to assume the simplest hypothesis compatible with observation, until it is ruled out by new observations. In this case, the simplest hypothesis is that the found particle is the SM Higgs. It still could be something more complicated (Supersymmetric Higgs, a composite Higgslike particle etc.). The lede already comments on this possibility.
Note, that this situation is not much different than that of other supposedly fundamental particles. E.g. not all preon models have been completely ruled out, however or quark article refers to quarks as fundamental particles. This in accordance with WP:CRYSTAL BALL.TR 15:34, 10 November 2014 (UTC)
This is a weird story, but it appears to be more about media sensationalism than physics. The article in question was posted on the arXiv more than one year ago and, at the time of writing this, it has collected 9 citations. The article itself is nothing special, it just argues that a class of Technicolor models can accommodate the existence of a particle with properties compatible with those of the 125-GeV scalar observed at the LHC. After what I would consider an unusually long review process - perhaps some referee was not convinced - it appears that the paper has been accepted by Physical Review D. Then on November 7, in another somewhat unusual step, the University of Southern Denmark, home to one of the authors, put out a press release about the publication of the article. It is this press release, with the suggestive title "Maybe it wasn't the Higgs particle after all", that was picked up by many science blogs in the past few days. In summary, this is just one of the dozens (or hundreds) of recent articles that proposed a BSM interpretation of the LHC findings, and not a particularly famous one if judged by citations. For some reason, the home institution of one of the authors decided to push the story, and it became viral on the blogosphere. I guess we can wait for the dust to settle before considering changes to the article. Cheers, Ptrslv72 (talk) 11:40, 12 November 2014 (UTC)

Quantum triviality[edit]

The following sentence was add to the article

There are also issues of Quantum triviality, which suggests that it may not be possible to create a consistent quantum field theory involving elementary scalar particles.

Obviuously, a statement like that needs a reference. Moreover, my recollection of the subject is a bit hazy, but doesn't quantum triviality put an upper bound on the Higgs mass? Wasn't it bounds like that that allowed the statement that the LHC would either find the Higgs or prove its non-existence?TR 14:56, 11 November 2014 (UTC)

Needs a criticism section[edit]

I've been reading article after article on notable scientists with PhDs who say the there's a good chance they did not find the Higgs boson. One of many examples is a team of physicists from Denmark, Belgium, and the UK question the CERN finding. One possibility is that its light techni-quarks. Another criticism is that the CERN data analysis team is not open to the public. 72.25.65.244 (talk) 18:50, 7 December 2014 (UTC)

But this article is about the Higgs boson. How do you criticise a particle? CodeCat (talk) 18:53, 7 December 2014 (UTC)
What?? The page needs a section that questions the finding of the Higgs boson? — Preceding unsigned comment added by 72.25.65.244 (talk) 18:58, 7 December 2014 (UTC)
It does not. A new particle has been found beyond reasonable doubt and this particle is called "Higgs boson" now. Yes there are models that might somehow be able to reproduce the observed mass, couplings, decay channels, limits on the width, differential cross-sections, spin and so on (I didn't see any model so far that takes into account all those measurements!) if you tune it enough to look exactly like the Standard Model Higgs boson without anything else. So what? More tests will most likely rule them out or make them pointless. --mfb (talk) 23:53, 7 December 2014 (UTC)
Physists around the world with PhDs at universities disagree with you. I'm not spending another second on this. Enjoy your Wikipedia. 72.25.65.244 (talk) 03:18, 8 December 2014 (UTC)