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B Problems with the Higgs model

  1. Jul 29, 2015 #1

    dno

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    The supposed discovery of the Higgs three years ago was widely celebrated. Nobel prizes were handed out and the mystery of the origin of mass is now explained. But does the Higgs actually explain mass at all?

    When thinking about the Higgs, I think it's best to ask these questions first:

    1. Discovering a particle at around 125 GeV doesn't mean it's the Higgs. For it to be properly called the Higgs boson, it would need to show evidence that it can bestow mass to a particle. Is this the case?

    2. The Higgs is theorized to be an omnipresent particle. For such a particle, it's been very difficult to find, hasn't it? Why? Isn't it supposed to be common?

    3. Since it's supposedly omnipresent, shouldn't it account for the majority of mass in the universe? Also, shouldn't a Higgs particle be coupled to every fundamental particle around since it's everywhere? For every electron, there's a Higgs boson. For every quark, a Higgs, and so on. Saying it interacts very weakly doesn't explain anything. It only explains the problem away.

    4. What gives the Higgs its mass? After discovering its "existence" that only lasted a fraction of a second, it disintegrated into various known particles, while leaving a trace. So if the Higgs is made up of standard particles, what made them and further, what made the Higgs? Another Higgs?

    These inconsistencies, among others, made me question physics entirely. These should've been asked after its proposal and further scrutiny should've been placed on the Higgs after it was supposedly discovered. When scientists accept a theory, without making sense of it adequately by asking the simplest of questions, they fail at being scientists.

    Thoughts?
     
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  3. Jul 29, 2015 #2

    e.bar.goum

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    The fact that you don't know the answer to these questions doesn't mean that physicists don't. In fact, it's rather egotistical in the extreme to assume so.
     
  4. Jul 29, 2015 #3

    Orodruin

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    Technically, it is not the Higgs particle which gives rise to masses, but the vacuum expectation value of the Higgs field. The Higgs boson is another property of this field, namely its excitations on top of the vacuum.
    Based on this, the Higgs boson should have a number of predicted properties, including its coupling strength to other particles. These have been checked and found compatible to current experimental precision.

    You are mixing the Higgs boson with the Higgs field again. All particle fields are everywhere, but what we call particles are excitations of these fields. In a somewhat lacking two dimensional analogy, the fields are the surface of the sea and the particles are the waves.

    No, again this is based on your mixup of field and particle.

    The Higgs mass is proportional to the second derivative at the Higgs potential minimum. In some sense, the Higgs' interactions with itself is non-linear and therefore gives mass to the Higgs.

    The Higgs is not made of standard particles so the question is moot. Do you think a photon is made of an electron-positron pair just because it can pair produce?

    They are not incosistencies, they are gaps in your understanding of the model.

    The Standard Model of particle physics is one of the most successful scientific theories to date. It is accepted because it makes testable predictions which have been verified to great accuracy. This is the only criterion in science, not that a layman can "make sense of it " by patching together misunderstandings based on popularised versions of the theory.
     
  5. Jul 29, 2015 #4

    ChrisVer

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    In addition to what Orodruin said on this, I'd also like to add that most of the mass of the matter in the Universe doesn't come from the Higgs Field. For example the Higgs could give the quarks their masses, but the masses of the quarks is not sufficient to add up to the proton's mass or the neutron's mass.. Mass of composite particles is affected by the constituent interactions.

    The mass of the Higgs Boson is a free parameter of the standard model. And it appears because you have higgs bilinear couplings (as the mass term appears for all scalars).
     
  6. Jul 29, 2015 #5
    Some people say that the higgs gives the other particles mass, but that's inaccurate (at best). E.g., the Higgs gives only about 2% of the mass of the matter around us in everyday live. The rest is provided by the spontaneous breaking of chiral symmetry and the trace anomaly in QCD.

    Within the standard model of elementary particles the condensate of the Higgs field provides mass to the quarks and leptons. The Higgs field itself has a generic mass term by its own, but with the "wrong sign", so that the local SU(2) x U(1) gauge symmetry is broken to U(1). The great discovery of Brout and Englert, Higgs, and Guralnik, Hagen, Kibble (all three articles in PRL 13, 1964) was that in the case of such a spontaneous breaking of a local gauge symmetry is an exception to Goldstone's theorem that applies to global gauge symmetries only. In the case of a spontaneously broken local gauge symmetry the "would-be Goldstone bosons" are lumped into the gauge fields of the broken part of the symmetry group and thus provide the longitudinal third component of a massive vector boson, i.e., these gauge bosons become massive. In the
    case of the electroweak standard model that means that the SU(2) weak-isospin gauge bosons become massive (these are the three W and Z bosons), while the unbroken electromagnetic U(1) keeps its massless gauge boson (the photon).

    Excitations of the Higgs field above its vacuum expectation value (VEV) appear as physical particles in the theory, and that's the Higgs boson. It gets its mass from the generic mass term and part of the Higgs-self interaction around the VEV. This leads to an effective mass term for the Higgs boson with the right sign.

    For the usual choice of a "minimal Higgs sector", where the Higgs fieldn is a SU(2) weak-isospin doublet (4 real field-degrees of freedom, of which 3 are providing the longitudinal components of the W and Z bosons and 1 describes Higgs-boson particles after spontaneous symmetry breaking).

    In the original version of the Standard Model, the fermions are massless. When you try to add a mass term by hand, it violates gauge invariance. If there is a Higgs boson, there would have to be an interaction term between the Higgs boson and the fermions, and that interaction term has the same mathematical form as a mass term for the fermions would have, if there were a mass term, and so therefore you can use the interaction term between the Higgs boson and the fermions for the mass term for the fermions, and thus you end up with a mass term for the fermions.

    What bothers me the most is that the tone of the original question was not "I don't understand it so please help me understand it" but instead "I don't undertand it so the scientists must be all wrong." Part of education is trying to get the student to think about their own education in the right way.
     
  7. Jul 29, 2015 #6

    Orodruin

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    While I agree, I believe most of your technical expose is lost on the OP based on the level of the thread.
     
  8. Jul 30, 2015 #7

    dno

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    Just to be clear: I'm not opposed in any way to learning more about this. The tone of "arrogance" stems from the belief that something's wrong as over the years I've become wary and grown skeptical of scientist's explanation about the world. When a leader of a field like Witten can one day publish an 800 page paper and later abandon it to work on something else, it raises flags. This is how I feel about supersymmetry, string theory, the anthropic principle - which to me is a strange form of reasoning. When the multiverse was invoked to explain the universal constants, I thought it to be lazily conceived idea. After more than a decade of multiverse debates, the idea hasn't even progressed. And so this is why I'm skeptical.

    As far as I know, only the mass of the Higgs was measured and no evidence of it giving mass to particles was discussed. This is what I wrote above as problem 1. All it needs to convince me is to give evidence that either the particle or the field bestows mass to other particles. This is its most essential property and that the Higgs's mass discovery alone shouldn't be enough to solve the problem of the origin of mass.

    Perhaps I wasn't careful enough about my wording. Interchangeable usage of boson and field when describing the Higgs is common. Regardless, if the particle is merely an excitation of the field, it means to create it, it had to be induced and didn't occur naturally. Raise the energy enough and who's to say a new particle won't come into existence? Raise it again, another particle could be created and again and again. To use your analogy: Suppose I drop an object on the surface of the sea. This would create waves but without the object and my intention, the surface remains undisturbed. But like the experiment, I could drop a heavier object and another one heavier and so on. The result would be that the waves created correspond to the objects dropped. So the following question is: What makes physicists so sure the Higgs boson wasn't only created?

    What do you mean when you say "non-linear"? Am I right in saying that the Higgs interacting with itself gives it mass?

    So, according to your explanation, as Higgs particles are only excitations, they're only made of energy? If so, shouldn't the Standard Model be separated into two types of particles, one short-lived and in some sense formless and the other with mass that's "permanent"?

    Shouldn't it be, though? According to SR, since energy is mass, and a field has energy, shouldn't this be accounted for? It would be inconsistent to say this field is omnipresent and then say it doesn't when one of its implications isn't wanted. It explains it away by sweeping it under a rug.

    Speaking of implications, what is the Higgs model role in cosmology? It pervades all of space so it's in the same domain as GR and dark energy on the largest scale while it also should have something to say about QM. Further, another problem I also have about the Higgs model is that it seems to be tacked on, that is, it isn't a part of a more comprehensive theory of the universe. Rather it's a patchwork idea much like inflation is to the big bang.

    To Jeffery: I don't mean to ignore you. But with a limited understanding and a decent amount of skepticism, my ammo is limited. I think some of your points are addressed
    above, though.

    Last, suppose for instance that someone came up with another way to explain the origin of mass. Should it be shot down completely? Is the Higgs result so unequivocal that it should go unchallenged? Are physicists 100% certain what they found was the Higgs and that the problem of the origin of mass has been solved?

    On a side note, as someone who's read popular accounts of physics and cosmology over the past decade, what hope is there of better science communication with the public when someone like me is being given inaccurate ideas by those who should know better? Why couldn't someone come up with a proper analogy of the Higgs without it being dumbed down to the point of being absolutley wrong. For example, with inflation, it can be said as space and time expanding exponentially. General Relativity as spacetime curvature. Big bang as a dense primordial fireball from which everything came into existence. With the Higgs, I'm being told practically everything I know is wrong. So what is it? Is it so impossible to come up with a better analogy to better understand it to dissect it?
     
  9. Jul 30, 2015 #8

    ShayanJ

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    You seem to demand that people come up with better and better analogies for physical concepts so that they can educate you to become a physicist and criticize other physicists only with learning analogies and without learning any actual physics. That's impossible. You can't become a physicist without learning physics!

    P.S.
    Right now, you're criticizing physicists while you have no understanding of the physics involved, that's what people call "arrogance"!

    Also, yes, sometimes there is no good analogy.
     
  10. Jul 30, 2015 #9

    dno

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    It's really pointless to go this route. I came here to ask questions and hopefully find answers. If I was so arrogant, I wouldn't have let Orudruin's post sway my views.

    And what's wrong with criticizing some views by physicists? Should they be immune from it? When Kaku goes on and on about his crazy ideas, should I just accept them? Debates about the existence of "nothing"? Right now no one knows the reality of the multiverse, so why are physicists criticizing each other about this? They're all equally ignorant about it just as you consider me ignorant of physics.

    And to ask better clarification about one aspect of physics is me asking others to educate to become a physicist? Really?

    How do you picture it? It can't be that this idea only makes sense through equations.
     
  11. Jul 30, 2015 #10
    There is nothing wrong IF one understands this views. You clearly don't, and that's the point. We study hard for over 5 or 6 years to understand things like Standard Model, and you just read some pop-science stuff and think it's enough to say things like: "When scientists accept a theory, without making sense of it adequately by asking the simplest of questions, they fail at being scientists.". It's not enough.

    Why? You can't truly learn and understand japanese poetry without knowing japanese. The same goes with physics - you HAVE TO use math, it's the language of physics.
     
  12. Jul 30, 2015 #11

    ShayanJ

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    Yeah, arrogance can increase!

    Do you also criticize neurosurgeons? What about rocket engineers? or any other professions? If not, what makes you think you can criticize physicists? I hope you get the point of these questions.

    Also, physicists aren't just a bunch of dudes always enjoying how much they agree with each other on all issues! The multiverse theory has only a few proponents among cosmologists right now and is the subject of debate among physicists themselves.
    Every theory in physics, has some proponents that work on it. But they're not like advertisers of a particular product that just want you accept their theory. What they do, is extracting the predictions of the theory about different situations. Then those predictions are compared with experiment. If they agree, good for the theory, if not, they see if they can modify their theory accordingly. If not, the theory is abandoned.

    Also, when you don't know enough to judge between different theories, you're not supposed to do so. So people outside scientific community are only supposed to accept theories which are mainstream and all physicists agree on them. If you want to be able to judge between theories, you should know enough physics and also be aware of experimental results. Otherwise there is no value to your judgements, even if you think otherwise.

    No, its completely acceptable to come here and ask for clarification. There is no problem with that. But criticizing physicists on the same issues that you ask clarification for here is really an inconsistent thing to do. If you know enough about them to criticize people, why do you need clarification? And if you need clarification, then how can you think you can criticize people based on the misunderstandings you're even willing to admit?

    Actually sometimes that happens in physics. Sometimes, only equations can describe the theory accurately and there is no other accurate way of communicating it, there is no accurate way of picturing it.
     
  13. Jul 30, 2015 #12

    Orodruin

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    This is wrong. We have measured the mass, the spin, and several of its couplings. And again, the Higgs boson does not give mass to particles, the vacuum expectation value does.

    This again comes back to your ignorance of what the model says. If the field exists (and it does, we can see the field excitations), then it has to give a mass to other particles proportional to its couplings with them. There is no way out. You would have a problem if you knew the field existed but particles did not have masses. The theory predicts a coupling proportional to the masses (or rather, masses proportional to the couplings) and that is exactly what we observe.

    Nothing is "made" of energy, this is another common misconception arising from popular science.

    No, you need to learn the actual theory rather than popsci before you can make any inferences about what the model says.

    No it is not - only in bad popular science.

    Your inference is wrong. The waves themselves propagate independently from what you dropped and the fact that there is the possibility of waves is due to the existence of the water surface. How the surface interacts with other things tells you its interactions, just as the Higgs field can interact with other fields.

    No, it should not. Again, you are not using the theory correctly and again it seems based on your superficial grasp through popular science. Nobody is sweeping anything under a rug here. Energy = mass is also a popsci oversimplification and you cannot just apply it to anything without understanding what you are doing.

    No, you just need to take ca 5 years of undergraduate courses in physics and preferably do a doctorate in high-energy physics, after that I will be happy to give you an account on how the standard model works.

    As someone else said, why do you expect physics to be reducible to a level where you do not need any prerequisites? I assume this is not true about other professions such as brain surgeon or helicopter pilot. They may be able to give you a summary of what they do and why, but it does not mean you will be able to fly a helicopter or be allowed to poke around in someone's brain.

    Because the way you are doing it, you are essentially telling the helicopter pilot that he cannot possibly fly the helicopter without getting out of the helicopter and turning the rotor by hand.

    Now why would you think that? Can you imagine an infinite dimensional vector space? In fact, the mathematics is what is the theory, anything else is just trying to make analogies from which no inferences can be made.

    This pretty much sums it up very nicely.
     
  14. Jul 30, 2015 #13

    BWV

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    Any layperson (like me) ought to place their confidence in the process of science rather than ambiguous descriptions used in popular science. I cannot judge whether any of the physics described in the OP is correct, but find it ridiculous to think that the OP is correct given how diverse the physics community is and how vigorously open problems are contested. The process of science works despite the foibles of individual scientists. The probability of any individual physicist being a charlatan is likely only slightly higher than the population as a whole (after all it does take a strong ego to become a physicist), but the probability that the entire profession mere charlatanism is absurd.
     
  15. Jul 30, 2015 #14

    mfb

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    There is evidence, but I think you do not have the required knowledge to understand it. If you think otherwise, read the publications from ATLAS and CMS.
    In your opinion, what can we physicists do better than now? Making up accurate analogies for everything is not possible.

    Add differential cross-sections and parity to that list. There are also weak upper and relevant lower limits on its lifetime.
     
  16. Jul 30, 2015 #15

    ChrisVer

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    have you ever studied particle physics or quantum field theory?
    These are some requirements in order to make a descent conversation on these stuff....
    Otherwise it's enough for you to understand that the higgs field gives the mass to elementary particles in the Standard Model. The fact that adding the proton quark masses up, you don't get the proton's mass, or that different configurations of quark states give different mass to particles, should already answer your question.
    Also the vacuum energy is infinite, this doesn't imply any infinite mass.

    I don't understand what you mean by this... what would be a more comprehensive theory of the universe? The Standard Model itself is not a fundamental theory, rather it's an effective field theory. That is known. Some people dislike it, some others accept it.

    The Higgs model wouldn't imply much in the cosmology that we know of... the Electroweak symmetry era ended at around the temperatures ~100GeV, where the universe underwent a phase transition (from the one vacuum to another).


    But nevermind these. The Higgs field etc, was a model to help us describe the symmetry breaking and the existence of massive gauge bosons and massive fermions.
    This model predicted the existence of (at least) one scalar particle (The Higgs Boson), which was actually discovered in ATLAS and CMS. So there is no way to deny the model (a physicist cannot deny the experiment), you can only try to find ways to solve the problems that it brings along.

    As for people comments, you should understand there is a slight difference between asking questions in order to understand something, and stating some things that are incorrect (as for example that phrase with the interchange of the field<->boson for the Higgs being something common).
     
    Last edited: Jul 30, 2015
  17. Jul 30, 2015 #16

    PeterDonis

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    Thread closed for moderation.

    Edit: it will remain closed
     
    Last edited by a moderator: Jul 30, 2015
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