Coming soon, Europhysics HEP 2011

In just four weeks the Europhysics HEP conference for 2011 will begin. This is a biannual meeting alternating each year with the ICHEP conference. This year it is being held in Grenoble and promises to be the biggest HEP event of the year with several hundred talks and poster sessions.

Abstracts of many talks have already been posted covering a wide diversity of experimental and theoretical subjects, but the main interest will be on the CMS and ATLAS searches. At the recent PLHC conference there were about a dozen reports using new LHC data. A couple form CMS and about ten from ATLAS. At that time about 200/pb of data was available. Although that was only a few weeks ago the LHC has now delivered much more and at Europhysics HEP they should be able to show the results of searches using 1000/pb. That is enough to say something significant about new physics. So far there are 13 abstracts posted for ATLAS that promise to use 2011 data and 20 for CMS.

These talks include a number of SUSY searches. If these find no new physics much of the most likely phase space for supersymmetry will be wiped out. SUSY in some form will still be possible, but it will have to be different from what the phenomenologists have predicted as the most likely scenarios. It will start to look like the last 30 years of research in hep-ph have been on the wrong track. If they do see hints something they will quickly be able to narrow down the available theories and tell us something very useful about the laws of physics.

Other presentations will look at the Higgs searches. With the 1/fb of luminosity likely to be included it should be possible to exclude the Higgs for masses above 135 GeV on the assumption that the standard model is the only physics in play. However, the standard model predicts vacuum instabilities for lighter Higgs masses. If this is the way it plays out we will know that something new must be there even if we don’t yet see it. The other possibility is that a promising signal for the Higgs will be seen at a higher mass. Either way there will be something to remember about Europhysics HEP 2011.

With just the 2010 data of 40/pb each, CMS and ATLAS have already produced hundreds of papers looking at different possible decay channels and search scenarios. As the amount of data available increases the possibility to look for rarer events in different channels goes up. With 1000/pb there will be a lot of things they can explore. Even with 6000 physicists between them divided up into small groups they will have to prioritize what they do for this conference. If you are one of those 6000 you should be too busy to be reading this so get back to work, and don’t expect any rest for a long time.

29 Responses to Coming soon, Europhysics HEP 2011

  1. Clara says:

    My own bet is that the standard model continues to hold, and that no new particles, no new symmetries, no mini black holes and no new dimensions will be found.

    This is also predicted from a simple fundamental principle by Schiller’s strand model. So far, it is the only model whose predictions match all experimental results. His summary at http://www.motionmountain.net/research.html is still looking good.

    And he even predicts the lack of a Higgs boson, and explains away the instabilities and unitary problems in other ways. This summer will be really interesting.

    • ervin goldfain says:

      “This is also predicted from a simple fundamental principle by Schiller’s strand model. So far, it is the only model whose predictions match all experimental results.”

      This is not true. There are other models that leave intact the structure of SM beyond the electroweak scale, are based on Higgs-free mechanisms for symmetry breaking and solve the unitarity problem in alternate ways.

      In my view, to gain acceptance, the strand model must be able to go beyond sketchy qualitative arguments. It falls short of this requirement, at least in its current form. For example, it fails to show quantitative results that match experimental data (numerical evaluation of SM parameters, cross-sections, invariant mass distributions and so on).

      • Kea says:

        Hear, hear. Clara’s statement is completely outrageous.

      • Clara says:

        Let me know those models, please – I’ll discuss them on my blog.

        The strand model makes a number of hard numerical predictions (W/Z mass ratio, hadron mass sequences, number of existing interactions, number of existing elementary particles) that match data.

      • Philip Gibbs says:

        I take it you mean postdictions not predictions. These quantities have been known longer than the strand model.

      • Kea says:

        Clara, I don’t see any decent mass predictions in your link above. He is even unaware of the Koide formula, it seems. And the braid idea really goes back to Bilson-Thompson and Kauffman and others.

      • Clara says:

        Well, predicting the number (3) of particle generations is a real prediction, in my eyes, as no other model I read about predicts that number. You may call that postdiction, if you want; but nobody else has an explanation for the number, so far. The same applies to all the other predictions/explanations I mentioned.

        The number of interactions and of symmetry groups varies greatly among unified models: E6, E8, SO(32), SU(5), SO(10) etc. Schiller’s strand model predicts that all of these are wrong, and that supersymmetry does not exist. You may call this a postdiction as well – who cares about the wording. In any case the strand model predicts the outcome of future experiments in a different way than almost all competing theories.

        Schiller quotes Bilson-Thomson, but his strand model is much more powerful: it explains quantum theory, general relativity, the three particle generations, the standard model Lagrangian and much more. Bilson-Thomson’s trinions do not explain any of this.

      • Philip Gibbs says:

        Schiller has written loads of great physics stuff and even cites my work in there somewhere, so I would love him to be right. Realistically the strand model is very speculative and theories like this have long odds. It will take a few real successful predictions, not postdictions for people to take much notice.

      • Kea says:

        Clara, do you actually know any physics? Many people have predicted these things you mention, and before Schiller did, as far as I know. The idea of three generations goes back to Ehrenfest, for goodness sake. Until GR is rigorously derived (and Schiller does not have the mathematical skill for that) there is nothing special about this particular idea, and I have been in favour of a braid particle spectrum for far longer than Schiller.

  2. Luboš Motl says:

    Dear Phil, I think that the statement

    “SUSY in some form will still be possible, but it will have to be different from what the phenomenologists have predicted as the most likely scenarios.”

    is unscientific in character. It’s a fact that given the existing knowledge of physics – and I really mean string theory only which is the only framework promising to calculate the values of the fundamental parameters and/or their probabilities – it is not currently possible to calculate which values of the parameters of the effective theories are “more likely” and which are “less likely”. It is not known which SUSY breaking mediation is the right one, or more likely to be the right one, and so on. All these questions – and others – are obviously subjective.

    So whatever “measure” you’re using is building on something that is not science. In particular, you may use some probabilistic distribution obtained from a statistical treatment of all preprints in hep-ph but that’s like the poll about the length of the emperor’s nose in China, if you know what story of Feynman I am referring to. If no one knows an actual valid scientific argument that would say which gluino mass is right and which gluino mass is wrong, you don’t improve the situation at all by averaging a larger number of people who don’t know.

    I still think it’s more likely than not that even the LHC will see SUSY – with the odds dropping in the obvious direction (but by unknown difference) every time the limits get more stringent – but I have always considered the hep-ph ideas that new physics has to be behind the corner to be a wishful thinking, a deviation from what I consider a good science, an attempt to get a fast profit and a sensationalist bias. There is nothing wrong about e.g. 5-10 TeV superpartner masses. This still removes almost all of the hierarchy problem as well and preserves gauge coupling unification. Phenomenologists have spoken about many tricks such as the “little hierarchy problem” but there was never any problem of this sort.

    It’s not only natural but de facto omnipresent if the mass ratios of nearby particles spans an order of magnitude or a factor of 50. It’s just how Nature operates. The fine-structure constant, 1/137, is small by itself, too. If someone thinks that Nature is obliged to reveal totally new qualitative physics every ttime we pay $10 billion, he may be my guest – but the complaints should be directed to Mother Nature and the complaining person is free to emigrate to another Nature.

    In my deep opinion, it’s damn important to separate actual scientific arguments that have some evidence – either empirical or theoretical evidence – that underlies them from completely blind guesses such as the statistical treatment of some mutually incompatible papers on an arXiv. The latter may belong to the work of the IPCC but surely not to science!

    Most of the detailed models studied in hep-ph obviously have nothing to do with the real world. At most one BSM model the hep-ph have ever studied has something to do with the real world. I think that every sane person must realize that at least 9,999 papers among mutually pairwise 10,000 incompatible papers have to be irrelevant for the reality. If they didn’t realize this counting, that’s too bad. And if one sharply well-defined model on hep-ph turns out to be right, that’s great – but that still shows that the other papers are wrong and it is completely misguided to distribute the “validity” among all the models, the right one and the wrong ones, and speak about statistical distributions and likely values. The very point of the experiments is, quite on the contrary, to discriminate and concentrate all the validity capital at most to one model, not to distribute.

    All the best
    LM

  3. Philip Gibbs says:

    I should perhaps have said “more favoured” rather than “more likely”. The point I wanted to make here is that what ever happens in the next few weeks it looks like it is going to make a big difference, unlike some of the previous exclusions. I still think that there is more likely to be something positive than something negative, and SUSY remains the best motivated theory we have. It will remain so even if there are null results, but instead of looking at the simpler SUSY models with a reduced parameter space they may have to look at other corners. That will only change if and when something else is found that works instead of SUSY.

    • Luboš Motl says:

      I agree (or I dare to refine) that what the LHC will release within a few weeks should a priori be expected to bring us a significant portion of the information that the LHC will ever bring us because by now, a real progress in the search for new phenomena has been made.

      Again, this is just an expectation that may turn out to be completely wrong later, when the LHC makes no discovery after 1/fb but it does make discoveries after 10/fb, or something like that.

      Still, the BSM literature is obviously unrepresentative of the people’s opinions about what the LHC finds. The LHC may find “nothing” – let me avoid what it says about the Higgs, there could be a “trivial Higgs” at 750+-320 GeV only – and many people counted this possibility as a likely option. It was always a likely option. But of course you won’t find hundreds of original recent papers about this BSM model because this BSM model is called the Standard Model.

      Of course that if there is just the Standard Model up to 14 TeV, the LHC won’t find anything new. But even this wouldn’t justify the statement that physics has gone in a wrong direction. It could still have been walking in a totally correct direction – the same one as the experiments – just the experiments haven’t managed to catch up with the theory yet, just like they previously couldn’t and didn’t at the Tevatron.

      But hep-ph, guessing particular models that could be relevant in the next experiment, was never walking in a single direction, anyway: it was walking in thousands of directions. A question is whether the right models are among these directions. But there’s no question that a vast majority of these directions are irrelevant for the upcoming observations.

      All the best
      LM

  4. Guest says:

    I look forward to read about the results presented at this conference.

    And I like Lumo`s comment which has almost gained the mass of a post ;-).

    This comment is a badly needed contrast to seeing some sourballs celebrating each null result of any kind of search for new physics.
    Otherwise one could be discouraged by the cheering sourballs from having fun with nice books about cool stuff :-/

    • Luboš Motl says:

      Thanks, Carla, one must be a real sourball to celebrate every null result haha. I am clearly a conservative physicist even when it comes to the expectation whether new things are ever observed – in most cases – but seeing nothing isn’t a reason to celebrate. Seeing nothing is a reason to do nothing when it comes to emotions, celebrations, and crying. :-)

    • Kea says:

      Those would be the sourballs with their own quantitative predictions (which the stringers can’t actually manage themselves) that have so far been correct?

    • Luboš Motl says:

      Dear Kea, one thing is very clear: sourballs haven’t said anything meaningful about physics so they couldn’t ever possibly be correct. Do you really need to explain this trivial point?

      • Guest says:

        Null results by themself are of course ok and valuable.

        But the sourballs are celebrate every corresponding paper as complete and definitive “game over” for new physics, for example SUSY and all stuff that depends on it.
        This leaves the impression that it is no longer reasonable wanting to learn more about “new physics” (?) …

  5. Kea says:

    No, I don’t need to explain it. There are intelligent experimentalists around who can check it for themsleves.

  6. Philip Gibbs says:

    Interesting comments about negative results.

    One of the most important negative results in recent times is the non-decay of the proton. Super-Kamiokande has pushed its lifetime up to about 10^34 sec while some GUT theories predicted lifetimes around 10^31 sec. A lot of models were ruled out. One of the strengths of SUSY is that it can still fit with this result.

    Super-Kamiokande got a Nobel prize for atmospheric neutrinos without ever a mention of the proton stability. Negative results are undervalued. If they had measured a lifetime instead they could have looked at the different decay modes and provided quantitative information that would have constrained models too. But with a few free parameters you could fit a lot of models to that data. The negative result may actually have ruled out more models and so given better information.

    The worst case scenario might be that the LHC just finds a SM Higgs around 140 GeV. The vacuum would be stable and the SM could hold up to higher energies. But we would still have dark matter, inflation, electro-weak precision measurements, running coupling constants that don’t meet, etc. They would have to find new models for all these things to explain what happens.

    I don’t think that is the way it will pan out but if it does it is not a disaster, It may just be hard to sell the beauty of such negative results to the public and the funding bodies.

    • ervin goldfain says:

      “The worst case scenario might be that the LHC just finds a SM Higgs around 140 GeV. The vacuum would be stable and the SM could hold up to higher energies.”

      I think that, for many theorists, one of the most surprising results would be not finding a light SM Higgs and no new physics. It is probably too early to draw definitive conclusions. But I agree with you on the impact of selling these null results to funding agencies.

  7. Tony Smith says:

    As to “The worst case scenario might be that the LHC just finds a SM Higgs around 140 GeV. The vacuum would be stable and the SM could hold up to higher energies.”
    and
    its “impact of selling these null results to funding agencies”

    why not sell the LHC as an explorer within the Standard Model plus Gravity of the energy region above electroweak symmetry breaking (order of 1 TeV) ?

    In that region, clearly accessible by the LHC, assuming only the Standard Model plus Gravity, the Higgs mechanism will not be around to generate mass, so everything will be massless, which is an interesting new regime that needs to be explored because:

    1 – The T and B quarks may not be so different,
    and the Kobayashi-Maskawa matrix may look very different,
    with possible consequences for CP violation (will it go away?
    will it get larger?)

    2 – Massive neutrinos may lose their mass, and so neutrino oscillation phenomena may change in interesting ways.

    3 – With no massive stuff, Conformal Symmetry may become important, leading to phenomena such as:

    a – Twistor stuff may be directly observable. See for example the book Mathematics and Physics by Manin, who says there:
    “… What binds us to space-time is our rest mass, which prevents us from flying at the speed of light, when time stops and space loses meaning. In a [massless] world … there are neither points nor moments of time; beings … would live nowhere and nowhen; only poetry and mathematics [ and the LHC ] are capable of speaking meaningfully about such things. One point of CP3 is the whole life history of a free …[ massless particle ]… the smallest event that can happen to …[ it ]…”.

    b – Segal conformal cosmological stuff (maybe Dark Energy) may be observable;

    c – Since the Conformal group acts in 6-dim spacetime, maybe two new large physical spacetime dimensions might emerge.

    Tony

    PS – The above suggestion should be supplemental to approaches based on superstring theory and GUT models,
    but
    the above approach emphasizes stuff that from an extremely conservative viewpoint should almost certainly be seen by the LHC in its energy exploration range,
    while
    superstring theory cannot say where its superpartner particles might be found (maybe they only appear at or near the Planck energy of about 10 to the 19 GeV, far beyond the reach of the LHC)
    and
    new GUT particles (leptoquarks etc) might only appear up near a GUT unification energy of 10 to the 14 GeV or so, also far beyond the reach of the LHC).
    Therefore,
    the above conservative approach might be an easier sell to funding agencies.

    • Ervin Goldfain says:

      “Therefore, the above conservative approach might be an easier sell to funding agencies.”

      ….assuming that funding agencies are going to understand all these proposals. Not an easy sell for sure!

    • Bill K says:

      To create a fireball of false vacuum, wouldn’t you also need an extremely high density? Wouldn’t you need to get the Fermi levels up to ~250 GeV also?

  8. Tony Smith says:

    As Ervin Goldfain says: “… Not an easy sell … ”
    but
    given the experience that physics lab/university PR people have in hyping the LHC with stuff from black hole creation to extra dimensions to recreating the Big Bang to listening to the music of the strings
    and
    given the success of popular physics books and media written and produced by marketing-oriented physicists
    and
    given the enthusiasm with which popular media propagate such stuff with impressive graphics and animations

    it seems that carrying out such a sell successfully ought not to be beyond the capability of PR people plus marketing-oriented physicists plus happily cooperative media.

    Tony

    • Lawrence B. Crowell says:

      The idea behind extra large dimensions is interesting, along with the prospect for black hole or AdS signatures. The compactification of a particle on a length scale R leads to a mass or energy that scales as ~ 1/R. If R is on the order of the string length this is a huge mass term. However. maybe this compactification scale has a renormalization group flow with the transverse energy of interaction. Then at low energy the compactification length might be on the order of {100GeV}^{-1} and which may becomes smaller at high energy interactions or transverse momentum. If there is a renormalization group flow of this sort it could then potentially be the case that at TeV energy scales there are amplitudes or channel processes corresponding to black holes or AdS-gluon chain physics.

      Standard QFT does not work beyond about 1TeV in energy. The Higgs mechanism is the obvious fix to this problem. However, the energy scale from transverse momentum scales >~ 1TeV may involve physics that is quite different from what we currently know.

  9. ervin goldfain says:

    Clara writes:

    “Well, predicting the number (3) of particle generations is a real prediction, in my eyes, as no other model I read about predicts that number. You may call that postdiction, if you want; but nobody else has an explanation for the number, so far. The same applies to all the other predictions/explanations I mentioned.”

    There are counterexamples to your statements. Regarding the number of generations see, for example,:

    http://dx.doi.org/10.1016/j.cnsns.2007.04.016

    I agree with Phil that the strand model is a very speculative construction, at least in its current form and content.

    • Clara says:

      Ervin, your article is not on vixra nor on arxiv, but I’d like to read it. And avoid wasting time with people who claim that the three generations go back to Ehrenfest – which is utterly wrong.

      • Ervin Goldfain says:

        Clara,

        We can continue the discussion elsewhere to avoid getting too much off the topic of this post.

        I can certainly email you a copy of my paper if you give me your contact information. My address is:

        ervingoldfain@gmail.com

        Cheers,

        Ervin

  10. tpqr13 says:

    Clara, I have this vague feeling that they see something.
    Maybe it’s because they re putting so much effort to accumulate data in the 7TeV energy regime and not thinking to go higher any time soon.

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