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I What can we gain/learn by knowing the Higg boson completely?

  1. Jan 6, 2019 #1
    This is serious question.

    What knowledge can we gain by knowing or understanding the Higgs boson completely? What is the Higgs..

    1. Easy problem?
    2. Moderate problem?
    3. Hard problem?

    I need to see the complete lists of it that may be spread in many obscure papers in Arxiv. So kindly enumerate them.

    Remember China would spend 5 billions dollars to create 100 TeV machine to probe the Higgs even if they seemed to realize no new particles could be detected. So there may be utmost importance mastering the Higgs.
    Just in two months ago.



    My interests in the Higgs is this part "The Standard Model leaves the mass of the Higgs boson as a parameter to be measured, rather than a value to be calculated. This is seen as theoretically unsatisfactory, particularly as quantum corrections (related to interactions with virtual particles) should apparently cause the Higgs particle to have a mass immensely higher than that observed, but at the same time the Standard Model requires a mass of the order of 100 to 1000 GeV to ensure unitarity (in this case, to unitarise longitudinal vector boson scattering).[162] Reconciling these points appears to require explaining why there is an almost-perfect cancellation resulting in the visible mass of ~ 125 GeV, and it is not clear how to do this. Because the weak force is about 1032 times stronger than gravity, and (linked to this) the Higgs boson's mass is so much less than the Planck mass or the grand unification energy, it appears that either there is some underlying connection or reason for these observations which is unknown and not described by the Standard Model, or some unexplained and extremely precise fine-tuning of parameters – however at present neither of these explanations is proven."

    Would understanding the Higgs make us understand other stuff like dark matter, cosmological constant, etc. better? (what is the other "etc"?)
  2. jcsd
  3. Jan 6, 2019 #2


    Staff: Mentor

    You can never measure every property and you can't measure any property exactly. "knowing or understanding the Higgs boson completely" is not a thing.
    I don't understand that question.
    The roughly 5 billion dollars are the price for a proposed electron-positron collider at a collision energy of about 0.25 TeV. It has been suggested to use the same ring for a proton-proton collider later - with an energy of up to 100 TeV and probably a much higher price.
    Maybe. In the worst case all measurements agree with the Standard Model - then we know that a couple of proposed alternatives can't be true but it doesn't help that much. In the best case we find properties that deviate from predictions. Any deviation would revolutionize particle physics, how exactly depends on what we find.
    The Higgs boson is the particle where we have the fewest and least precise experimental measurements, so naturally many physics programs focus on that, but the Chinese collider (both variants) would do much more than just measuring properties of the Higgs boson in more detail.
  4. Jan 6, 2019 #3
    It means what is the mystery of the Higgs that is the easiest to solve, moderate to solve, and very difficult to solve. Example of difficult to solve is figuring out how the mass came to be by computations. So the Chinese collider would aim for the moderate or the very difficult? Easy to solve categority may be simply figuring out if it's composite or the vacuum metastable or stable or unstable.

    What do you mean "would do much more than just measuring properties of the Higgs boson in more detail.". Supposed the Chinese were convinced by Dr. Yang arguments nothing else would likely be seen: no new particles, no hidden dimensions, no mini black holes, no supersymmetry particles.. nothing. So it's still worth it to spend 20 billion dollars to study the Higgs only?

    If the Higgs still matches the prediction to the letter and no deviations. What does it mean?

    What kinds of deviations of the Higgs can as you describe "revolutionize particle physics"?
  5. Jan 6, 2019 #4


    Staff: Mentor

    I don't think these categories are meaningful, and apart from compositeness your questions are all about the theoretical side. Colliders are tools of experimental particle physics. They will tell you the mass and lifetime of particles, their decay modes and much more, but they won't solve problems of theoretical physics on their own. If one of the measurements deviates from predictions this will help theoretical physics a lot, but see above: How exactly depends on what deviates from expectations. If all measurements are in agreement with predictions then we just know some ideas were dead ends, but it doesn't tell us which idea is the right one.
    See the article you linked, or the Wikipedia article, or similar sources. The Chinese collider can also measure the Z and W bosons in more detail, look for new particles, measure some more properties of other particles and so on.
    It means theorists have to work harder. We know the Standard Model can't be everything, we just don't know yet what else there is. The open theoretical problems can give some guidelines but so far we don't have a theory that solves all of them.
    Every deviation would. The decay of a Higgs to two muons is more likely? Less likely? The decay to two photons is more likely? Less likely? Any other decay? The angular distribution of the decay Higgs->4 muons shows a different distribution than expected? The lifetime of the Higgs is shorter or longer than expected? We produce Higgs bosons where we don't see their decay products? We produce two Higgs bosons together more or less often than predicted? And so on. Every possible deviation would help theorists a lot. Similar for all other particles.
  6. Jan 7, 2019 #5
    Thanks for all your information. It has finally made me understood a lot regarding the china colliders and googling many news makes more sense.

    So the CEPC is just prelude to the Super Proton Proton Collider with center of mass of 100 TeV. https://arxiv.org/abs/1507.03224

    But looking at china citizens commentary about it. I read that

    "While USA is pushing the muon-collider with full-speed, why Gross is not pushing MC as a Chinese program? Obviously, Gross is still hoping for the miracle on SUSY. He wrote: {Of course the SPPC will also explore much higher energies, and will have the power to produce new particles [as SUSY] that are nearly ten times heavier than can be produced at the LHC. It will certainly continue the search for supersymmetry (amongst other things), precisely because supersymmetry is currently a hypothesis.}

    Roughly, we can divide human constructions into four categories.

    One, tool: with definite utility mission, such as, house, high way, vehicle, etc.
    Two, toy: for unlearned to learn.
    Three, art: to express the human spirituality, above the utility.
    Four, tomb: to house the dead.

    Beijing Electron-Positron Collider (BEPC) was a toy by design. So, it has produced absolute nothing (a big zero), and it is expected and excused. But, the 100 Tev pp collider can never be claimed as a toy while all the data and evidences already guarantee that it will produce absolute nothing (a bigger zero); as SPPC is definitely a SUSY machine while SUSY is definitely dead below 100 TeV.

    So, SPPC cannot be a tool for new physics. It will be a joke as a toy. It is simply a tomb which house the dead dream of a wrong physics (SUSY).

    They three also emphasized one ‘non-science’ argument: {this could be a great chance for China becoming the leader in the particle physics field.}

    The future of the particle physics is on the muon-collider, not pp-collider. The best physicists will not waste their live with a dying project. Only the third and fourth level people will use this kind of dying project as their welfare check department."

    The gist of it (even if you will not agree with the commentary which is so few in the internet so allow some critiques of the china colliders) is that only the Muon-Collider can prove if quarks/leptons have substructure. Is it not? What if the future of physics is not really SUSY but Compositeness Model? Then even the China SPPC would be dead end. Won't a muon-collider be more promising??
  7. Jan 7, 2019 #6


    Staff: Mentor

    I don't know where you read that but it is full of factually wrong statements and various other problems.
    No, proton-proton colliders can possibly see that as well.

    A muon collider is much more challenging - it is an interesting concept, but there is a lot of research that has to be done to make it work. It provides clean collisions but the collision rate would be very low.
  8. Jan 7, 2019 #7
    Ok. I guess this is the definitive guide to physics beyond the standard model that can be probed by the CEPC


    "Naturalness and Higgs Measurements".

    The CEPC will start taking data in the 2028 according to https://en.wikipedia.org/wiki/Circular_Electron_Positron_Collider

    So it looks like we have to wait another 10 years for SUSY and company.

    The CEPC project is almost 90% good to go? Would its computers be in Chinese or English? (seriously)

    Hossenfelder said the LHC "will remain the largest particle collider in human history." I guess she spoke so soon.
  9. Jan 7, 2019 #8


    Staff: Mentor

    Don't trust these extremely preliminary timelines. Even if the project gets the final approval (sounds likely now, but we don't know yet) it is unclear when things will start.
    CEPC can only cover a small range of SUSY parameter space directly, although the precision experiments with known particles still contribute to the search. Meanwhile the LHC will accumulate more data.
    She didn't, please don't misquote physicists.
  10. Jan 7, 2019 #9
    I didn't misquote him. Don't you read her blogs regularly? Lately she wrote this article:


    "In summary: Since the naturalness-based predictions did not pan out, we have no reason to think that the remaining LHC run or an even larger particle collider would see any new physics that is not already explained by the standard model of particle physics. A larger collider would be able to measure more precisely the properties of already known particles, but that is arguably not a terribly exciting exercise. It will be a tough sell for a machine that comes at $10 billion and up. Therefore, it may very well be that the LHC will remain the largest particle collider in human history."

    Will CEPC and SPPC funding be all on China account. Or would other countries help? Can China be influenced by outsiders? Can Hossenfelder constant negativity influence it?

    I wholeheartedly support the CEPC and SPPC project. It's the only way humanity can move forward. The physicists who don't support it are those who thought there was nothing more in the world than the standard model and quantum gravity which is unreachable in any future particle accelerator if it's near the planck scale and not closer as mentioned in Warped Passages.

    For those who don't who still don't support CEPC and SPPC. Just visit china and see for yourself the open secret of why there is categorical need for beyond the standard model machines, because there are phenomena that can only be explained by new beyond the standard models. This is why the real Elite or inner circle in China is so convinced wholeheartedly for the CEPC and SPPC. Although of course there are distractors in china because they don't want to look at the evidence which the rest of the world still haven't seen. It's so damn obvious. Because the evidence is censored elsewhere in the world, just discover it yourself. Even mentioning it here can get this thread locked or deleted. Its paradoxical that physicists need guiding light or principles for BSM. But when the guiding principles are right under their noses. They strongly clobber it without even hearing the sides or looking into it. This is because as Lee Smolin and Hossenfelder reasoned in their books. Physics community is like herd community.

    Whatever, I will support the CEPC and SPPC and will defend them against those who are against it.
  11. Jan 7, 2019 #10


    Staff: Mentor

    The original statement had an important context:
    China needs international expertise for CEPC and even more for SppC and they will look for international funding as well.
    Super-KEKB (operational), ILC (probably dead), CLIC, FCC-ee, FCC-hh, plasma wakefield acceleration, muon collider, ... and that is just the collider section of particle physics.
    Or they think other projects have a better knowledge gain to cost ratio. Again you misrepresent what others say.
    You think they care about particle physics? They care about the prestige, the international experts and the useful side-projects such a machine brings.
    What the heck is that.
  12. Jan 7, 2019 #11
    Can other mentors give me permission to share just one link for the open secret that gives the Chinese so much motivation for the CEPC and SPPC? It involves the Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, too.
    Last edited: Jan 7, 2019
  13. Jan 7, 2019 #12
    Darn. I may risk getting this thread locked or moved again (sorry Auto-Didact).

    I'm trying to re-read Hossenfelder book "Lost in Math" to review her arguments. I want to ask about Naturalness as it applies in daily life.

    When we drive a car, dance, or go about our daily routine. Is it Naturalness (with formulas close to unit 1 and not 0.000000637)? Or what is the counterpart of "Naturalness" (used in physics and particle physics) in daily life. This analogy is to understand or master of the concept of Naturalness arguments in Hossenfelder book which is becoming best seller. Her book and arguments can even influence funding and support for the China's CEPC and SPPC which still require international cooperation and collaboration from the experts.
    Last edited: Jan 7, 2019
  14. Jan 7, 2019 #13


    Staff: Mentor

    Is it peer-reviewed science?
    Hard to tell the quality of a link without seeing the link - if in doubt you can send me a private message.
    I'm not sure if there are good analogies, but here is a try:
    If careful measurements have established that a parking lot has a width of 1.63456619494 m and a car has a width of 1.63456619436 m this might be coincidence - but you'll spend some time to determine if both values might have some causal relation.
  15. Jan 7, 2019 #14
    It may be peer-reviewed in 2050 when the world is more advanced and new generations of physicists replaced our current ones. Let's not mention it again here as this public forum is to discuss mainstream current views.

    How about this. A car moving across the street at an angle. An ant or any insect which can only see 2D can detect the circles or round shape and let's say the insect can measure the wheel to be 2.36352662234324 foot diameter, and detect the windshield to have area of say 9.62664673245345 sq. foot. They can't figure out how it works or why they move (not together since the car is circling the ant at off angle). So an ant Sabine among them may say never to bother with any computations because they are only random and no statistical precedence. The truth may be something they will never figure out. That it's a car with person driving it. This is good analogy of naturalness right? We may not have the tool or understanding at present time to realize the higher level of naturalness (the car with humans driving it) which produced those ratios.
  16. Jan 7, 2019 #15


    Staff: Mentor

    That's the point of the discussion. Can we find a theory that explains these values? Is there such a theory?

    In my example the deeper "theory" is: The car manufacturer or the parking lot builder looked at the other object to set the width of their object.
  17. Jan 7, 2019 #16
    That's what will arrive maybe 50 years into the future. We are dealing with very very difficult theory that is not only in the cutting edge of physics but way way beyond it.

    The CEPC and SPPC will give us more clues. Unfortunately. Some seem to be against it. Do you think Hossenfelder is not against them or publishing materials discouraging it?

    If many western or European physicists are against it. Do you think the Chinese can figure out how to build the CEPC or SPPC by their own?

  18. Jan 7, 2019 #17
    For some figure. Right now who are the physicists pessimistic of the CEPC and SPPC?


    1. Dr. Hossenfelder
    2. Dr. Yang
    3. (pls add).

    optimistic or actively supporting it:

    1. the rest?


    1. don't care if it succeeds or not.

    I want it to succeed because the CEPC and SPPC is our future and humanity's last hope.
  19. Jan 7, 2019 #18


    Staff: Mentor

    Someone could find a solution this year (and then people work out the details in the following years). We don't know.
    Not necessarily.
    What gives you that impression?
    Why do you think this would be necessary just because some people think other projects are more important?
    Certainly not with the given time frame and quality.

    For every big project there are many people who support it and many who do not. That is how opinions work.
    This is nonsense.

    Stop making wrong claims please, otherwise I'll close this thread.
  20. Jan 7, 2019 #19
    I'm most interested in the Hierarchy Problem and Vacuum Metastability. The CEPC and SPPC can address them.. don't they?

    Or do they need more than 100 TeV machine?

    US won't develop any muon collider? Do you think there is stil possibility quarks are composite or have subquarks. What kinds of exclusions before we can consider it as 100% not composite?
  21. Jan 8, 2019 #20


    Staff: Mentor

    CEPC can measure the Higgs mass more precise but the dominant uncertainty for the vacuum stability question comes from the top mass where CEPC won't contribute. SppC might help with it - not clear how much, the LHC will make very accurate measurements already.
    Unless one of the machines finds something completely new they won't help with the hierarchy problem.
    We don't know if such a collider will be built in the future. There are some people working on some critical concepts like the cooling at the moment (MICE).
    You can never be sure that they are not composite, but it is quite unlikely already.
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