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Data Review Brings Major Setback In Higgs Boson Hunt

Velcroman1 writes "The quest for the elusive Higgs boson seemed over in April, when an unexpected result from an atom smasher seemed to herald the discovery of the famous particle — the last unproven piece of the physics puzzle and one of the great mysteries scientists face today. Scientists with the Tevatron particle accelerator at Chicago's Fermilab facility just released the results of a months-long effort by the lab's brightest minds to confirm the finding. What did they find? Nothing. 'We do not see the signal,' said Dmitri Denisov, staff scientist at Fermilab. 'If it existed, we would see it. But when we look at our data, we basically see nothing.'"

34 of 180 comments (clear)

  1. Please explain to this non-physics-type geek by halivar · · Score: 2

    What are the implications of such a particle not really existing in the first place? In terms of how we think our universe works?

    1. Re:Please explain to this non-physics-type geek by SimonTheSoundMan · · Score: 4, Funny

      Religious people will say "We told you that God isn't a particle".

    2. Re:Please explain to this non-physics-type geek by Richard_at_work · · Score: 5, Insightful

      If it exists where people are looking for it, it will confirm certain current theories. If it doesn't exist where people are looking, it damages certain current theories. If it doesn't exist at all, it calls for a complete rethink on many things.

      Basically, if the Higgs Boson exists where people think it does, it means our ideas about how the universe is constructed are well founded and once again science has provided evidence to back up its theories. If it doesn't, then that opens up doors for radical rethinks on those ideas, meaning possible new directions in which to go and new theories to seek evidence for.

    3. Re:Please explain to this non-physics-type geek by m50d · · Score: 3, Informative
      The elegant standard model of particle physics only works because the particles don't have intrinsic mass (they get their mass from coupling to the higgs field). This allows a symmetry between the three "families" of particles (electron/muon/tau, neutrino/mu neutrino/tau neutrino, up/strange/top, down/charm/bottom etc.)

      So if there is no Higgs boson then we're certainly missing something. I'm not sure if it's possible for the Higgs field to exist and not carry particles; certainly you'd normally expect for particles to be able to form in a field. If there's no Higgs field then either some other mechanism gives particles mass (and I'm not aware of any real proposals) or the standard model is wrong (which it probably is wrong, but we're short on replacements). If the standard model collapses, that puts us back to having 20+ different "fundamental" particles, all discovered through experiment, with no real idea of how they're related or how many more are out there.

      --
      I am trolling
    4. Re:Please explain to this non-physics-type geek by Anonymous Coward · · Score: 5, Informative

      First, to be clear: the Fermilab people haven't shown that the Higgs boson doesn't exist. They just didn't find it.

      If the LHC doesn't find it, then we can start saying it doesn't exist. That would pretty much invalidate the standard model of particle physics, which is the currently best-accepted theory we have (because it gets most things right). If the standard model is wrong, it opens the door for other physical theories to be considered. Right now we're not taking those other theories so seriously because they all get one thing or another wrong, but if the standard model is also wrong about the Higgs, then there's no particular reason to favor it over other theories that also get one or two things wrong.

    5. Re:Please explain to this non-physics-type geek by Paracelcus · · Score: 2

      Perhaps some aspects of current physical science need to be re-visited? Like maybe the Euclidean point that was the initial state of the universe was not a point at all? Maybe there is no need for a Higgs Boson?

      --
      I killed da wabbit -Elmer Fudd
    6. Re:Please explain to this non-physics-type geek by Richard_at_work · · Score: 5, Informative

      Some aspects of current science always need to be re-visited, and science in general isn't touchy about doing so.

      There may not be a need for Higgs Boson as you suggest, but the current theories suggest that there is - which is why its being looked for. No one has yet come up with a credible alternative that doesn't first throw out the entire current model, and quite honestly its currently cheaper to spend the money looking for the Higgs Boson than it is recreating the entire current model from scratch and coming up with evidence to support the change.

      But the chance that the Higgs Boson might not exist is not a reason not to look for it - because looking for it will either prove it does exist, or that it doesn't exist where we thought it did. Both outcomes are beneficial, and just because we didn't find it doesnt mean the money was wasted - the fact that it wasn't where we thought it was is great science in itself, because it brings new data to the table.

      Plus of course the chance that other discoveries may be made during the hunt for the Higgs Boson.

    7. Re:Please explain to this non-physics-type geek by Mr_Huber · · Score: 5, Informative

      Currently, things weigh more than they should. The mass of a particle is a function of the kinetic energy of the particle and it's component parts, if any. If we run the numbers, we get good masses for some particles, not good masses for others. A proposed solution to this problem is the Higgs field, a nonzero field that permeates space. Anything coupling with this field gains additional mass through interaction with the field.

      Picture a person at a party. Normally, they are free to move through the party fairly easily. Now make that person famous. Admirers flock around, and the celebrity has trouble moving. Nonfamous people are particles that do not couple with the HIggs field. Celebrities are particles that do couple with the field, surrounded by a paparazzi of virtual Higgs particles.

      Nice theory. It fills a gap in the standard model and now the math all works. So now we have to find the particle. You need the mass of a particle to find it in an accelerator. Roughly (very roughly), you need to create collisions where the sum energy of the little explosion is about that of the particle in question, then watch a statistically large number of those to see if something matching your particle appears. If it does, it's off to Stockholm for dinner with the king. If not, it's back to the drawing boards.

      The problem is, the theory doesn't predict the mass of the particle. It doesn't even say if it is one particle, a family of similar particles or a family of different particles. So there's a wide spread of masses to examine. And all the masses are really high, far higher than any other existing accelerator could reach. So we have the new CERN experiment, slowly scanning the possible masses, looking for the particle.

      If we don't find that particle, then we're back to square one, why are some particles heavier than predicted? For decades, we've assumed it was some sort of variant of the Higgs boson. But if that's not the case, it's back to the blackboard for more theories.

      In general, this is a problem for particle physics. Finding or not finding the particle will affect chemistry, biology and general astronomy not at all. It might or might not have an affect on cosmology, but that's hard to say without a particle to talk about. More interesting for cosmology is that while searching for the Higgs, the experiment might come across more esoteric things, such as evidence for supersymmetry. Evidence for supersymmetry would automatically generate the prime number one candidate for dark matter. And nailing down the properties of dark matter would give us another probe of the Big Bang.

      More information than you wanted probably, but I hope it helps.

    8. Re:Please explain to this non-physics-type geek by cfc-12 · · Score: 2

      It means the universe has disappeared and been replaced by something even more bizarre and inexplicable.

    9. Re:Please explain to this non-physics-type geek by Richard_at_work · · Score: 2

      Depends on what you mean by "falsified".

      Can the LHC team fake it? Certainly they can, but it would be a complex fabrication - if their results showed that the HB fell outside of the limit of anything other than the LHC then independent verification would be impossible until another collider in the LHCs class could be constructed to run the same tests. In the mean time, as support for their findings, the LHC team would be pressed to release the raw data from the collisions - terabytes of data that would need falsifying to support the findings.

      Would a falsification stand up for long? It depends how well it was done - science has several times been caught out by well done fakes to support one theory or another, but ultimately they have all fallen to scrutiny - or have they? Well, if any haven't, then they are standing up to scrutiny - what does that mean? :)

    10. Re:Please explain to this non-physics-type geek by marcosdumay · · Score: 2

      Yes, it is expected to be in a certain mass range, have a certain spin (zero), a certain electric charge (zero), a certain color (none - "color" refers to strong force charge), and so on. The LHC can sample all the "places" it is expected to be, and can prove it doesn't exist. Now, of course, somebody can come after that with a different theory, with a different particle and name it after Higg.

      IANAP by the way.

    11. Re:Please explain to this non-physics-type geek by slimjim8094 · · Score: 3, Informative

      Falsifiability is when you describe an experiment that would show your theory to be false. Falsifiability is a requirement of a valid hypothesis. Gravity would be falsified by showing that objects with mass didn't accelerate towards each other - if you could show that, you disprove gravity. Evolution is falsified by watching a species spring from nothing. Creationism can't be falsified because "it's all God" - anything that happens that you didn't expect, God could've done - which is why creationism isn't science.

      It's not about fabrications or hoaxes. The GP's question (I hope) is whether somebody could construct an experiment that shows that the boson *doesn't* exist, at least not as we understand it.

      --
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    12. Re:Please explain to this non-physics-type geek by DerekLyons · · Score: 2

      The data might be there, but you just sent thousands of scientists off on a theoretical goose hunt and cast doubt on every large scale experiment currently running.

      No I didn't. I started with one guy, or a couple guys that get a flash of inspiration over a beer, or a handful at a weekend BBQ or a conference. You're correct in assuming there is unlikely to be a large scale assault - you're incorrect in assuming that's the only possible route.

    13. Re:Please explain to this non-physics-type geek by __aamnbm3774 · · Score: 2
      I'm still shocked by this outrageous quote from the summary

      the last unproven piece of the physics puzzle

      maybe according to the Current standard model...maybe...but hardly the last physics phenomenon that exists, even at microscopic levels.

    14. Re:Please explain to this non-physics-type geek by slew · · Score: 3, Informative

      Ok, here's the higgs boson car analogy...

      Suppose you have car and emperically you figure out how to drift it into many different turns. In certain configurations, you notice a certain amount of differential side-slip and you collect data. You make a theory about drifting based on various combinations of tires (particles), and road surface types (fields). One thing that you notice is that you don't really know why there's certain side-slip angles with different treads, so you propose a theory that the coupling between the tires and the road surface is different between these situations and that affects the skid dynamics (apparent mass), that you experience. Okay now you have this great theory and a bunch of empirical data of skid dyanmics that works for you by assigning magic number (masses) to various combination tires and surface types.

      But you wonder if you can find a way to predict the dynamics and you come up with this idea that this coupling is a fundamental relationship of the coupling between tires and road surfaces (kinda like friction). Your theory is that there is some interaction between the tire and road which is like "friction" caused by the tread design and tire deformation amount. So you devise an experiment to see if you can find the thing causing this "friction".

      The higgs field is analgous "friction" and the search for the higgs-boson is analagous to the search for the source of friction. If you think of friction being caused by atomic forces, there is some range of forces that can cause the macroscopic changes in skid dynamics that you see empirically. Likewize with Higgs, the higgs-boson need to be found in a certain range of collision energy if it is consistant with the standard model to match the empirical data of obverved mass and coupling constants up to Planck scale energies (where gravity is more quantized and mass probably has different physics).

      If we find the thing that causes atomic forces that is consistant with our theory of "friction" (with say the tread design, or say the tire deformation amount), then probably something else explains the skid dynamics that isn't "friction", but something else. So we have to determine by experiment what the skid dynamics are for each tire and road combination. Likewize, with w/o Higgs we are struggling to have a theory of mass, but that doesn't mean mass (and the resultant dynamical behaviour) doesn't exist, just we don't know why it exists and can't predict it from known theories.

  2. The Presence of Absence by The+Living+Fractal · · Score: 4, Insightful

    Sometimes not seeing what you expected is worth seeing in itself...

    --
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    1. Re:The Presence of Absence by Richard_at_work · · Score: 2

      My exact first thought on reading the summary was "well, its not a setback, its just one place less to look!"

    2. Re:The Presence of Absence by grasshoppa · · Score: 2

      The lack of data itself is as interesting as a "Well that's odd" moment in other experiments.

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  3. Re:Budgets by The+Living+Fractal · · Score: 4, Insightful

    No, you don't. Finding nothing in specific conditions is different than finding nothing in your backyard. I doubt you can collide subatomic particles in a controlled environment in your backyard.

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    I do not respond to cowards. Especially anonymous ones.
  4. Re:And of course... by The+Living+Fractal · · Score: 3, Insightful

    I disagree. Sometimes math fails (root: because we fail at math) and the only recourse is to smash things together to see what falls out.

    --
    I do not respond to cowards. Especially anonymous ones.
  5. Re:And of course... by Richard_at_work · · Score: 4, Insightful

    And of course you can provide evidence to back your assertion that the entire thing needs a rethink? Just from your comment, I'd rather give these scientists billions of dollars for the LHC than give you $10 for lunch.

  6. Re:Budgets by Sir_Sri · · Score: 2

    At the TeV scale anyway.

    You can pretty easily get a particle accelerator that will fit in your yard, it's just not going to be powerful enough to see anything new.

  7. Re:Budgets by jmd_akbar · · Score: 2

    When something touches even the air, it's particles are colliding with something..

    So there you are..

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    Nothing here... So... SHOOO!!!
  8. Re:And of course... by bhagwad · · Score: 2

    If anything, this just shows me the way science should work. An assertion is taken, tested impartially and if found wanting it's discarded without a second thought. No emotion, no hysterics. Just science.

    Your worries about a huge conspiracy are shall we say...a tad loony?

  9. THIS by Anonymous Coward · · Score: 2, Insightful

    For sure --- I've been reading Dr. Dobb's Journal of Tiny BASIC Calisthenics & Orthodontia for years and yet no publicly funded research money has ever gone to this cause. It is beyond a crying shame.

  10. Re:And of course... by m50d · · Score: 2
    You know how they "fixed" the ether? It wasn't with pen and paper, it was by thinking about the implications, then doing the experiments (in particular, michaelson-morely), and then looking at the results. The same thing they're doing now with the Higgs.

    I don't think the Higgs exists either. But it's the best candidate explanation for observed phenomena. There is an upper limit on the mass of a standard model Higgs, and testing in the relevant range is reasonable; even if we don't find the Higgs, we'll likely find something interesting. Of course, if you have a better candidate model, then by all means make the predictions, publish them, and see whether they match what the LHC comes up with.

    --
    I am trolling
  11. The Higgs Boson disappears my socks. by Oxford_Comma_Lover · · Score: 4, Funny

    > I doubt you can collide subatomic particles in a controlled environment in your backyard.

    Of course I can. That's where I keep my old dryer. I have long hypothesized that the Higgs Boson is responsible for the disappearance of my socks... it is an interesting particle, ineffective against sock/antisock pairs, leaving unpaired socks in its wake, explaining the unaccounted for shortage of antisocks in the universe.

    --
    -- IANAL, this isn't legal advice, and definitely isn't legal advice for you. Also, Squee!
  12. Um guys by voss · · Score: 2, Funny

    "I'm pretty confident that towards the end of 2012 we will have an answer to the Shakespeare question for the Higgs boson, to be, or not to be?" Rolf-Dieter Heuer, director general of CERN, said at Britain's Royal Society."

    Id be perfectly okay if you wait until 2013 to get your answers. Its not that I believe all these December 22,2012 things its just that
    some idiot who forgot to carry their zero might be stupid enough to rush something and accidentally cause some sort of catastrophe. Lets all just
    shut down all the accelerators on December 14th,2012 and give everyone a holiday until January 7th, 2013.

  13. Not the Higgs by wuzzeb · · Score: 5, Informative

    Sorry, the summary and title is just plain incorrect. This announcement has nothing to do with the Higgs.

    A few months ago, CDF claimed that they detected a new particle which could not be the higgs, but was speculated to be a new particle. As explained here, it wasn't possible for the new particle to be the Higgs.

    Today DZERO announced that they did not see any signal where CDF claimed to see one. So one of the two projects has an error in their analysis.

    More info orig, new announcement, DZERO refutes, another source, even another source

    1. Re:Not the Higgs by renhwa · · Score: 2

      This comment should be emphasized. The summary and title are way off the mark.
      1. This was not a data "review," but rather an entirely new analysis. Fermilab has two experiments that study proton-antiproton collisions, named CDF and D0. CDF published the original paper, and then D0 tried to verify their claims. Reproducibility of results is a tenet of science; having multiple ~independent experiments at Fermilab allows results from one experiment to be verified at another. This story demonstrates exactly why we need independent verification to be confident in a result.
      2. This is not a setback. The CDF bump was unexpected and quite exciting, but not vital to the progress or science, nor anybody's daily business in the particle physics world.
      3. This never had anything to do with the Higgs. Generally, people have not been regarding the CDF bump as a possible Higgs signal, but rather an indication of something new.

      See D0's paper. And...let's stay away from FoxNews for science writing.

  14. Re:And of course... by Anonymous Coward · · Score: 5, Insightful

    Actually not. Naively explained so you can understand it, the Higgs mechanism to work needs a Higgs mass between 114 GeV upwards to ~170 GeV. Outside of that region things don't work and it's safe to say you have to look for better ideas.

    The reason why physicist think the Higgs boson is there it's because 3/4th of the idea has already been discovered, the W^+ , W^- and Z bosons. What is left of the picture is that 1/4 which correspondes to the Higgs in the electroweak theory. If there is supersymmetry there might be 5 Higgs bosons which would make the discovery of each of them a little bit more difficult. But hopefuly feasable in the LHC.

    If you let me, I would give an analogy*. Think of you trying to solve a puzzle, a very complicated one indeed. After years of work you manage to assambly a consistent arrangement of all the pieces that not only fits, also gives a pretty picture. All there's to find a piece that you lost somewhere in the room to put it in it's place. At this point you are pretty confident that the chances of it not fitting are small, and that you got it right. But physicist don't take this for granted, they wan't to find the piece and prove it. And if it doesn't fit, don't worry, we will work on the puzzle again.

    *NOTE: If needed the image of the puzzle can be that of a car.

  15. Re:What nonsense. by MightyMartian · · Score: 2

    Translation: I have blinders on, can only see in one direction and would, if in charge, starve key areas of basic research whose benefits we cannot guess at this time.

    --
    The world's burning. Moped Jesus spotted on I50. Details at 11.
  16. Let's set the record straight by jma34 · · Score: 2

    Let's get things straightened out. About a month ago the CDF experiment at the Tevatron at Fermilab found a "bump" in their data. It was statistically significant and was unexplained. This "bump" cannot be the Higgs boson from The Standard Model because it has the completely wrong cross-section. This was a fully public result from the CDF experiment.

    About the same time there was a "leaked" abstract from an internal note from the ATLAS experiment at the LHC which claimed to have a signal for a Higgs boson. This was never a public or published result.

    Now today we have an announcement from the D0 experiment at the Tevatron that they looked into the CDF bump and see nothing. This isn't a set back for the Higgs since it was never about the Higgs. The ATLAS leaked abstract has never been confirmed even by ATLAS so lets not get our underpants in a knot. Lets also not conflate the two since they don't have anything to do with each other.

  17. Re:And of course... by Artifakt · · Score: 2

    What would count as good evidence that the standard model has a big flaw in it? When people started thinking the epicycle model was wrong, it happened for several reasons (paraphrasing Thomas Kuhn for much of this):
            By Copernicus' time, 1) there were a lot of accumulated observations that no one had during the first few hundred years, and new tools made those latter observations more accurate. 2) The formulas to calculate epicycles grew more and more complex to account for those observations, and people could point to the history of the model to show what that trend implied for its future. People lost confidence that the next tweak would be the last. 3) the epicycle model still didn't predict some basic things, such as the exact start time of some planets appearing to precess, accurately enough.
            So, for 1), the standard model hasn't been around for hundreds of years. In the time it has been around, we have developed much more powerful accelerators, but we haven't invented a significantly new class of tools (such as the Galilean or Newtonian telescope, or reasonably accurate to a few seconds a day clocks, all of which came in as epicycle models were being rejected). Progress on the observational side has all been evolutionary, not revolutionary, so progress on the theoretical side will tend to mirror that, rightly or wrongly.
    For 2), The Higgs is one of a very few testable predictions which could add some math to the rest of the standard model. It makes the math a little more complex to include it, but by itself, it doesn't suggest that every 20 years or so, we will again have to add some more complexity. Evidence for condition 2) would have to come from more than just Higgs Boson research, i.e. finding some other unexplained particle that definitely isn't the Higgs to suggest we are seeing ever mounting complexity. A possible Higgs candidate slightly outside the projected ranges, or something which seemed mostly Higgslike but for some odd property (say, a cluster of related particles all with no spin or color, but slightly varying energies), wouldn't make most theoreticians rethink the whole model so much as try to tweak it a little.
    3) We could argue that 3) is being met, in the form of the gravity related incompatibilities of QM and General Relativity. If we still face that question in 100 or 200 years, more and more working scientists will regard it as a situation like 1), and arguments that the change needed is major will gradually gain traction.

    --
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