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First steps after the Higgs Boson

  1. Oct 4, 2011 #1
    The standard model predicts, and relies on, the higgs boson. We have not witnessed it yet, because the energies required to do so were beyond us in the past.
    Current models predict, however, that (if the Higgs Boson exists) CERN WILL see it.

    I know its still early, but CERN hasn't turned up any evidence yet...At what point would it be reasonable to conclude that the Higgs does not exist? No matter how many times we fail to find it experimentally, there is always a chance that the next run will turn one up. When do we reach the tipping point?

    IF we were to conclude that the Higgs is not a reality, what should our next steps be? Are there any current models of the world without it? Do we start from scratch or is there any evidence that its possible to salvage the standard model without it?
     
  2. jcsd
  3. Oct 4, 2011 #2

    Bill_K

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    The good news is that the LHC has been doing very well. The bad news is that it hasn't found anything yet. As of today the accumulated data amounts to 4/fb, equal to about 270 trillion collisions. We'll get to 5/fb by the end of the year (the prediction had been only 1/fb). By the end of 2012 perhaps 15/fb (about a quadrillion collisions) and if still nothing is found, this should be enough to definitively exclude the Higgs' existence.

    The optimism surrounding the inauguration of the LHC didn't make clear what a long and difficult process this might turn out to be. Everyone hoped for some quick results. But the Tevatron at Fermilab ran for ten years before achieving its goal of finding the top quark, and the hunt for the Higgs might very well take that long too. Here's the problem. Even with a quadrillion collisions to work with, the only way of spotting the Higgs is to filter the data on every expected property. In other words you must assume in advance you know precisely what it is you're looking for, what it can decay to and in what proportions, everything except for the mass. If you fail to find it that way, you must then broaden the search, which can require far more data and far more time.

    There are many, many alternatives to the standard Higgs, including multiple Higgses, composite Higgses, spin one particles, and so on. To really find the answer could wind up taking not just 15/fb but 10 or even 100 times as much.
     
  4. Oct 4, 2011 #3
    Well its good to hear that there are alternatives to the standard Higgs, I realize data sifting is a long and tedious process. I wonder if funding for the project would continue if the project needed so many fb of data :/
     
  5. Oct 5, 2011 #4
    If one talks about the Higgs as it is described in the standard model enough data should be collected this year to exclude it OR to see some hint of where it might be. This means that the question about a standard model higgs might be settled next summer, and should definitely be settled with the data collected next year.

    There are many other higgs possibilities apart from the standard model higgs, and if one, or more, of these are realized there is no guarantee that it will ever be discovered.

    Cheers
     
  6. Oct 5, 2011 #5
    In prediction, data luminosity in this year (about 5/fb)will be enough to see the evidence of higgs. But the biggest problem now is how to identify the partille such as photon or quark and so on.

    Fermi lab found top in their run i, but failed to find higgs in run ii. We should be patient. I always believe that the truth is there, someday we'll get it.
     
  7. Oct 5, 2011 #6
    What if the Higgs Boson is actually the equivalent of dark matter?
     
  8. Oct 5, 2011 #7
    ?

    These are two completely different things....are you very familiar with dark matter?
     
  9. Oct 5, 2011 #8

    ZapperZ

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    That doesn't actually make any sense if you understand the physics of each one. That's like asking "What if photons are actually electrons?"

    Zz.
     
  10. Oct 5, 2011 #9
    Wikipedia has an interesting collection of beliefs about dark matter.
     
  11. Oct 5, 2011 #10
    Wikipedia has an interesting collection of beliefs about dark matter that are often incorrect and may confuse someone who doesn't understand the proposition.

    Err on the side of caution when reading a wiki, check any interesting information against more reputable sources.
     
  12. Oct 5, 2011 #11
    From Wikipedia we read:
    The Higgs boson is the only elementary particle in the Standard Model that has not yet been observed in particle physics experiments. It is a consequence of the so-called Higgs mechanism, the part of the SM explaining how most of the known elementary particles obtain their masses....

    Relying on the concepts behind this Wikipedia excerpt, and the reasonable assumption that dark matter has mass, then isn't it reasonable to imagine that Higgs bosons and Dark Matter might be related.
     
  13. Oct 5, 2011 #12
    The Higgs Boson is a part of the standard model. Dark Matter is a name given to whatever substance makes up the difference between the mass of the universe predicted by the Standard Model and the observed mass of the Universe.

    Which is why one cannot be the other...if the higgs were dark matter, our problems would be solved.
     
  14. Oct 5, 2011 #13
    Dark matter is conjectured for the purpose of explaining unobserved mass. Dark Matter is a useless concept without mass...
     
    Last edited: Oct 5, 2011
  15. Oct 5, 2011 #14
    A bit bold to state given that 90+% of the contributors are quantum and nuclear physicists from the many accelerator and synchrotron sites all round the world. What pray tell are more reputable sources that those folk who publish in AIP etc.?
     
  16. Oct 5, 2011 #15
    Do you suggest that dark matter does not have mass?
     
  17. Oct 5, 2011 #16
    I am suggesting the opposite. Dark Matter HAS to have mass. That's the whole idea of dark matter.
     
  18. Oct 5, 2011 #17
    I can edit a wiki article right now. Wiki articles CAN have false information, and are not published for academic reference. At the very least, it is usefull to google whatever information you find in a wiki just to verify it from another source.
     
  19. Oct 5, 2011 #18
    Well then, perhaps you can help all of us understand the differences between "substance", "matter" and "mass".

    The phrase "observed mass" seems a stretch, but I'll let it pass for now. My question is: Does the mass of Hydrogen gas, claimed by many to account for 90+% of the universe, dominate our universe as suggested by 90+% or has dark matter take over as the dominant "substance"?
     
  20. Oct 5, 2011 #19
    Yes, you can momentarily edit a wike article to change what it shows, but their are Wiki-Hawks who monitor various high profile pages and "fundamental" info pages that are very soon reverted to Status Quo beliefs and concepts.
     
  21. Oct 5, 2011 #20
    Substance: A word I use loosely because Dark Matter is a loose concept, not a specific thing. It is used to describe a discepancy in the observable universe.

    Matter: Everything in this universe that is not energy, space, or time.

    Mass: A property of matter theorized to be carried by the Higgs Boson, much like the relationship between electrons and the electromagnetic force.

    What does this have to do with whether or not the Higgs Boson could be dark matter? Yes, the Higgs has mass. If you are curious about the prevalence of Hydrogen gas in the universe, that is something that can be researched(google?) and which I don't know off the top of my head.
     
  22. Oct 5, 2011 #21
    OK. I understand the question. Bear with me.
    Let me divert to the use of the word "observable".
    What scientific instruments are used to "observe" matter, mass or substance?
    What physical properties are being detected by those scientific instruments?
    If dark matter has mass, and mass is detectable by our current day scientific instruments, then why can't we "detect" or "observe" dark matter?
     
  23. Oct 5, 2011 #22
    Unfortunately, we don't have a "mass detector." We can use radio telescopes, thermal imaging, and spectral analysis to find objects and determine their distance, size, and makeup. We can deduce mass by understanding the gravitational effects of what we see and knowing the intrinsic properties of what we observe.

    Dark matter is a thought.

    Put simply, when we look out into the universe, we see more "gravity" than there should be. What I mean by this is that the observed matter in the universe does not account for the activity we see: We assume that this means there is something out there that we are not detecting. We call this "Dark Matter," and some calculations reveal that up to 90% of the universes total mass could be "dark matter."
     
  24. Oct 5, 2011 #23

    ZapperZ

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    The electric field and a charge are "related". But does that mean that electric field IS charge? Think!

    Zz.
     
  25. Oct 5, 2011 #24

    ZapperZ

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    But your standard, we don't have a charge detector, a particle detector, a wave detector, a immorta1 detector, etc.. etc. Show me where you think you have a "detector" of anything, and I'll show you a "thought".

    Zz.
     
  26. Oct 5, 2011 #25
    Your description is limited to measuring various wavelengths of light (dipole oscillations) at a distance. So what causes dipole oscillations? The answer to that is the explanation for how we observe (detect) objects and matter at a distance.

    Nearly all astronomical physics is based on measuring light, but matter, in close proximity, can be measured by magnetic field strengths, and electric field strengths. Is it fair to say, that we have no clue as to whether or not dark matter or dark energy does or does not have either electrical or magnetic properties?

    If you read my earlier posts, you should find that astrophysicists have claimed for many years that hydrogen accounts for more than 90% of the total universe mass. Isn't it strange how a new concept with no proof of existence can so quickly displace an older "fact".

    I still take issue with the use of the word "mass".
     
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