SUSY was not round the corner

ATLAS have produced new exclusions limits for SUSY (Taffard) models using jets plus missing transverse energy from 1/fb of data. These go well beyond previous limits leading to the conclusion that “SUSY” was NOT “just rounnd the corner” as theorists hoped.

Where does this leave SUSY? Well SUSY is a many parameter theory with a lot of variations and it remains the most plausible explanation for many observations. More searches may find it.

Ultimately it will be the Higgs searches that have the final say. SUSY predicts a light Higgs with higher mass partners. If the Higgs is found to be something different SUSY will be much harder to motivate. Until the Higgs sector is resolved, SUSY lives on.


36 Responses to SUSY was not round the corner

  1. Luboš Motl says:

    A genuine elimination of a part of possibilities.

    Why is the generic limit still not at 1 TeV? I thought it would already be there. Do you understand what is meant by the “quark mass” in the real world where there are clearly many quark flavors with different masses? It’s hard to figure out whether such bounds eliminate a particular model or not.

  2. paolo says:

    if You forget about WeSeeBumpsEverywhereCDF experiment there are not so many observations to be explained with it. susy is nice but not now, just not now (and foreseeable future)

    • Philip Gibbs says:

      As we keep saying, even if everything is negative this week the implications would be profound.

      The Higgs would be pushed back to regions where it does not work as a standard model particle. We would have to wait for more data to finish the exploration of the Higgs mass range, but that will be done probably by the end of this year.

      Everybodies favourite model would be ruled out or its motivation would be weakened or lost. Theorists would have to use the new constraints to find new models that fit while still explaining dark matter and inflation. Without these results they would have no idea where to concentrate their efforts.

      That is why the LHC (and other experiments) are certain to be successes, whether we like their results or not.

  3. Luboš Motl says:

    Dear Philip, your comment happens to be randomly linked to what I was going to write.

    Half an hour ago, Fermilab has released a press release claiming that the Higgs is most likely between 114 and 137 GeV, see my blog for a link.

    I am very happy that the jungle of cheap models that the phenomenologists have been producing for years – physics that was wished to be behind the corner, much like the predictions of a warming doom – will be entirely exterminated.

    Needless to say, I agree that whether someone likes the results or not, the LHC speaks an authoritative language.

    Cheers, LM

    • Philip Gibbs says:

      Fermilab will be assuming that their precision tests are good, but they require too many assumptions. Tomorrow ATLAS and CMS could show us a signal at 200 GeV 🙂

    • Paul says:

      JFC, Lubos, did you have to bring up global warming. How are we supposed to trust an ideologue like you about anything.

    • Luboš Motl says:

      Dear Paul,

      ideally, you shouldn’t trust anyone – and the problem why millions of people have been deluded and believe in medieval superstitions is that they have replaced reasoning (and even elementary looking at the reality with their eyes) by a “belief”. You should do your best to check the data yourself and do the best estimates of the causes of the variability and the predictions for the future that you are capable of, given your education and math skills.

      It just happens that when you do so correctly, you will find out that any scaremongering about the climate contradicts science. The climate will continue to change just like the weather and the atmospheric physics as any time scale just like it did at any point in the recent 4.7 billion years. This is the *only* result of pure science in this conglomerate of questions. Any kind of scaremongering or “proposed cures” is ideology, and the more scaremongering someone is or the more “policies” someone proposes, the more ideology he is doing.

      Cheers
      LM

      • X says:

        That is why string theory has been considered a religion

      • Luboš Motl says:

        String theory has only been considered “religion” by people who have feces in their skulls. But that’s true for any important theory in science.

      • X says:

        The analogy with religion has been noted by a number of prominent physicists (including Nobel winners as Feynman or Glashow). Superstring theorists as Jim Gates agree:

        “String theory is often criticized as having had no experimental input or output, so the analogy to a religion has been noted by a number of people. In a sense that’s right; it is kind of a church to which I belong. We have our own popes and House of Cardinals. But ultimately science is also an act of faith—faith that we will be capable of understanding the way the universe is put together.”

        http://www.pbs.org/wgbh/nova/elegant/view-gates.html

        The reason for disagreement with you is that all of these people do not have theirs skulls empty as you have Lubos.

      • Ulla says:

        One reason for the analogy is also the Religion War symbolism. Everyone is fighting for the truth, trying to discredit the other part, often with ugly means, again demonstrated by Lubos. Why M-theory is considered the true ‘religion’ is because its status.

        We should all realize it is just a religion, no fact. Here its incompetence to proove anything is dramatically demonstrated. The fecal affect hardly improves theory.

      • Dilaton says:

        X:

        Phil and Lumo do a very cool job to inform us in real-time about the latest results from the EPS-HEP conference and even generate prelininary combined plots before these are officially presented 🙂

        I think THAT is the purpose of the last posts here indcluding this one and the corresponding comments!

        You have chosen the wrong blog for Your purpose 😉

      • X says:

        Ulla: ok.

        Dilaton: But neither Lubos reply to paul nor to me was about the conference. If you don’t like him (you) get corrected, just don’t post crap against the climate guys and remain *on topic*.

      • Alex says:

        X,

        That Jim Gates quote is a terrible quote. There is this deep distinction between informed faith, and faith for no good reason or even in light of unreason, and they are so different that it is hardly appropriate to use the same word. There is good reason to have “faith in science” because we simply know that it has always worked in the past – in fact it seems to be the only thing that has ever produced reliable and useful results. If he’s taking his comparison seriously, that’s problematic.

  4. Ulla says:

    If the symmetry is screwed maybe the Susy island after all has a chance?

    http://www.fnal.gov/pub/presspass/press_releases/2011/CDF-Xi-sub-b-observation-20110720.html

  5. Kea says:

    Remains the most plausible? You’ve got to be bloody kidding …

  6. Felix Lev says:

    The fact that Lambda > 0 implies that dS is more relevant symmetry than Poincare or AdS, right? But the dS algebra does not have a SUSY generalization.

    • Alex says:

      Hi Felix Lev,

      Why do we have to insist on a global SUSY realization in dS if we have supergravity at our disposal? That sounds kind of artificial to me

      • Felix Lev says:

        Hi Alex,

        Thank you for your comments. Supergravity, as well as standard gravity and General Relativity, is based on a flat spacetime background. Then to explain the fact that Lambda > 0, supergravity should treat the term with Lambda as dark energy or other fields, right? Then we have the standard cosmological constant (CC) problem (in standard quantum gravity with a reasonable cutoff, a disagreement by 122 orders of magnitude between theory and experiment). Supergravity can reduce the order of disagreement but to what extent? Is there any other way to explain the CC problem in supergravity?

      • Alex says:

        Ah now I get where you’re coming from. I thought you were talking about consistency. Yes indeed, I am not aware of a good solution of the cosmological constant problem using supergravity. I suppose if you break SUSY at a high scale as the usual models do, with a TeV scale graviton or so, you basically have standard FRW spacetime and something that looks like global susy locally, so my intuition would be that radiative corrections to the cosmological constant would be like the usual global SUSY claim, namely >40 instead of 120 orders of magnitude in E^4 units. The only tentative solutions ever which I’ve heard lately are constructions in d>4 which had a sort of self-tuning behavior which would reset the net 4D cosmological constant to close to 0 in a dynamical fashion. But those were kind of vague, and I don’t understand them in any detail.

      • Felix Lev says:

        Consistency is important too. In my papers I argue that the notion of the spacetime background is not physical. On quantum level, symmetry should be defined not such that the spacetime background is flat or curved but by commutation relations of operators describing a system under consideration. Then if we accept dS symmetry, the cosmological acceleration has a trivial explanation without dark energy or other fields. However, in standard quantum theory (over complex numbers) the dS algebra does not have a SUSY generalization. I am not saying that the global dS symmetry is the ultimate solution but at least, from the point of view that Lambda > 0, it’s more relevant than Poincare or AdS. In a quantum theory over a Galois field it’s possible to reconcile dS with SUSY.

  7. Kea says:

    Lambda = 0 with a varying c.

  8. […] valores posibles para la supersimetría a baja energía. Como nos resumen Philip Gibbs en ”SUSY was not round the corner” (merece la pena ver las figuras) y Peter Woit en “Results from EPS-HEP 2011,” […]

  9. Felix Lev says:

    Kea, in the literature I did not see such an explanation of the cosmological acceleration (that Lambda = 0 with varying c). Could you, please, elaborate?

    • Kea says:

      Louise’s varying c blog discusses the no DE scenario within the FRW context, but I prefer to discuss it in the context of QG itself, wherein one expects Lambda=0 as a condition upon emergent geometry. Since modern holographic cosmologies talk about varying hbar, and we know that alpha cannot vary much, it is very silly to have foibles about varying c.

  10. Philip Gibbs says:

    CMS were going to provide a series of ten posters covering SUSY results with 2011 data. They have all been withdrawn except one which only used 36/pb. Looks like they could not get it ready in time.

  11. A little clarification concerning variable c cosmology. The only manner to make sense of it in General Relativity framework is to start from Robertson-Walker line element ds^2= g_aa*da^2-a^2 ds_3^2 . gaa==c^2 would be the natural identification for variable c. In standard cosmology c goes to zero at the limit of Big Bang and in TGD framework where space-time is a 4-surface this indeed has concrete interpretation in terms of how light-velocity is measured in practice: it takes more time to travel from point A to B along wiggled surface than along geodesic of imbedding space. In Louise Riofrio’s cosmology c becomes infinite. This result is a complete catastrophe since the time behavior of energy density and thermodynamics would change completely. It would not be a Big Bang anymore.

  12. phil says:

    I’m impressed by how well the LHC experiments are nailing the SM predictions, when seeing these null results. At this early stage it wouldn’t be so shocking to see some minor anomalies due to imperfect understanding of the detectors, but everything we see (at least) seems consistent with the systematics being very well controlled.

    Gives confidence for when (let us hope not if) something new is claimed!

  13. X says:

    A little precision: These go well beyond previous limits leading to the conclusion that “SUSY” was NOT “just round the corner” as [[[SOME]]] theorists hoped.

  14. […] but ruled out even at low mass. A SUSY multiplet can still work but searches for MSSM signals have excluded the best parts of the SUSY spectrum. There is certainly a big conundrum here. Theorists may be sent back to the […]

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