Large Hadron Collider provides 1 inverse femtobarn for CMS and ATLAS, already!

Today at 21:10 hours European Time the Large Hadron Collider passed an important milestone when it reached 1/fb of integrated luminosity delivered to each of the large experiments CMS and ATLAS. The third major proton experiment LHCb which limits its luminosity has around 0.35/fb. These figures include the 47/pb delivered in 2010, but after another one or two good runs the total for 2011 alone will also surpass the one inverse femtobarn milestone.

Update 14-Jun-2011: With another good run today the total delivered for CMS passed the 1/fb mark for 2011 data alone at about 20:25.

This is an impressive achievement for the worlds most powerful particle accelerator at CERN which had originally expected to collect this amount of data only by the end of 2011. Better than expected performance now means that it records about 30/pb worth of collision data each day on average. With about 120 days of proton physics left this year, the beam operations team can expect to deliver at least 4.4/fb this year if they continue at this rate.

Potential luminosity increases

There is still some potential to increase this figure if they can continue to increase the number of protons circulating in the rings. The current quantity of 1092 proton bunches circulating in each direction will shortly be increased to 1236 and then finally 1380 once they overcome difficulties with power to the RF systems. This will increase the luminsity by 25%. Another goal will be to increase the efficiency by keeping the collider in Stable Beams for longer. Recent figures show that this state is only achieved for around 40% of the time due to a variety of technical issues. As these are sorted the figure may go up to 60% or even higher to give 50% more data. If this can be done quickly it would bring the expected total for 2011 up to around 7/fb. At 1380 bunches the rings are full to capacity with current bunch spacing so further improvements this year are only possible if the bunch intensity can also be increased, but this is not yet planned. 5/fb to 7/fb is already a spectacular number to aim for and they may not want to put these numbers in danger by taking such risks.

Expected conference announcements

The amounts of useful data recorded by the experiments is typically 90% to 95% of the amounts delivered. In a few days these figures will also pass 1/fb and this should be in time for the next big particle physics conference EPS-HEP2011 at the end of July. At last weeks PLHC2011 conference we already saw a few results using 200/pb, one fifth of the current standing. However, there are many standard searches for which we have still only seen plots using the 40/pb collected last year. For example the classic dimuon resonance curve has not yet been shown in updated form for either ATLAS or CMS. This could be because it was too dull to show. The dimuon signal is very clean but it is not expected to be the first place where new physics will appear. On the other hand, it may not have been shown for the opposite reason. If it had an inconclusive signal of a new resonance then they would surely want to wait for more data before showing it.

When will the Higgs be seen?

To get a better impression of just how significant the quantities of data now being collected are, it is useful to look at the projected Higgs Limits as shown in this figure.

With 1/fb of data there will either be a signal or an exclusion for the Higgs boson above 130 GeV. If it is excluded then it will be known to lie between the 115 GeV limit previously set by LEP and a new limit of 130 GeV. This is highly significant because the standard model on its own predicts that the vacuum would be unstable if the Higgs has a mass less than 135 GeV. New particles such as those predicted by supersymmetry would be needed to restore stability. In other words, this exclusion expected from 1/fb would be indirect evidence of physics beyond the standard model at the electro-weak scale. The EPS-HEP conference is likely to be a historic event where they will either describe the first signals for the Higgs Boson or the first good evidence for new BSM physics. If you want to attend today is the last day to register at the standard fee or 350 Euro!

If EPS-HEP is an anti-climax, the next big particle physics conference is Lepton-Photon 2011 during the last week of August. Another femtobarn of data will be available for analysis in time for that. There are smaller workshops and seminar opportunities going on all the time so a new discovery can come at any moment, but the physicists do like to time their results for these big events.

By the end of the year the situation will be even more dramatic. About 5/fb should be available, enough to exclude the Higgs boson at all masses, or more likely to discover it. If it is indeed a light Higgs there is a good chance that some other new particles will be discovered too.

What if it does not show up?

The calculations that are used to calculate the exclusion limits are themselves based on assumptions that the Higgs will decay according to the predictions of the standard model. If the standard model is ruled out by not seeing the Higgs then these calculations will themselves be invalid. For example, a possibility is that there are heavy unknown particles into which the Higgs could decay. If these new particles produce jets that are hidden in the sea of background QCD it may be much harder to detect it. Another even weirder possibility is that the Higgs boson just isn’t there. If nature is devious enough we could still see no new particles this year.

57 Responses to Large Hadron Collider provides 1 inverse femtobarn for CMS and ATLAS, already!

  1. Ervin Goldfain says:

    Congratulations LHC for this impressive milestone!

  2. Glenn says:

    Thanks Phillip for your insightful commentary (as always) on all things LHC. I am not a physicist, but I always look here first for a very readable summary of what is going on.

    I hope they have enough time to analyze 2 / fb by the end of the summer (and go through the arduous review process for any results…)

  3. [...] hecho eco de esta noticia (como muestra el banner de viXra log). Philip Gibbs pone hora al evento, 21:10 hora de Madrid. Enhorabuena a todos los técnicos, ingenieros y científicos del LHC del [...]

  4. algernon says:

    ok, we got the inverse femtobarn, we got the glasses, now we only need the champagne bottle boson and we’re all set :)

  5. Kea says:

    Nature is not being devious. Fairy fields obviously do not exist. It was obvious ten years ago that they do not exist. The only deviousness is in the self delusion of thousands of arrogant stringers.

    • Philip Gibbs says:

      Kea, I missed the bit where you explained why the Higgs”obviously” does not exist, and what alternative mechanism for EWK symmetry breaking you propose. This would be a great moment to elaborate and secure your place in history :)

      I am also confused anout why you think it is just string theorists that expect it to be found. As far as I know the only physicists who have suggested it won’t be found are Hawking, Veltman and you, and I’m not so sure about the first two.

      • Kea says:

        Phil, there exist many theorists who don’t believe in the Higgs boson. And I use the term stringer (as opposed to String Theorist) in a wide, literal sense. EW symmetry breaking must be viewed from a quantum gravitational perspective, not from gauge theory. In the braid formalism, the other particles are specified by braid diagrams, whereas the Higgs mechanism is the process of defining emergent spaces from their underlying noncommutative and nonassociative categorical geometry.

        Why do you think we talk so much about the quantum Fourier transform? It sends a 1-circulant to a diagonal and a 2-circulant to a codiagonal, so that a SU(2)xU(1) matrix is sent by the inverse transform to a sum of a real 1-circulant and an imaginary 2-circulant, like for the mixing matrices. These things are more elementary than anything in the local theory.

      • Just to clarify terminology: a SUGRA supermultiplet obtained from usual theory of representations, is a “quantum gravitational perspective” or a “gauge theory perspective”?

      • Ulla says:

        A quantum gravitational perspective is not so easy to start with.

        Kea, you dislike arrogancy, but you are not humble yourself, long from it. Then there are humble correspondents that are most arrogant. And some hates arrogancy, but sometimes sounds very arrogant. This is no good startpoint to decide whom to listen to.

        “the Higgs mechanism is the process of defining emergent spaces from their underlying noncommutative and nonassociative categorical geometry.” – I asked about this once, but got no answer. Maybe you have an answer now? Where is it published?

      • Philip Gibbs says:

        If the symmetry breaking is due to quantum gravity does that mean we will see some quantum gravity phenomenology at the electro-weak scale, or just no Higgs?

      • Ulla says:

        That was a good question!

      • Lawrence B. Crowell says:

        I have pondered this. The theory of superconductivity involves a quartic potential and Bogoliubov coefficients. This is suggestive that since the Higgs field is quartic and Bogoliubov coefficients there may be some connection between the Higgs field and quantum field theory in curved spacetime. I am sure this has occurred to others as well.

        I have pondered something further along these lines. The sine-Gordon equation φ_xx – φ_tt = sin(aφ) has a potential V(φ) = cos(aφ)/a. I include a constant a << 1. This is approximated by V(φ) =~ 1/a – φ^2/2 + a^3φ^4/4!, which is similar to the Higgs potential. Further, this is S-dual to a theory of fermions with a quartic potential, the Thirring fermion model. So maybe hyperbolic dynamics is on AdS_2 with this funny perturbing potential constructs a Higgs model or something similar to BCS superconductivity.

  6. The non-existence of Higgs is of course far from “obvious”. Higgs vacuum expectation is not necessary for massivation. It is not however specialist knowledge that the massivation of gauge bosons requires Higgs to give them longitudinal polarizations if they are originally massless. As they should be in order to obtain gauge invariance necessary for a renormalizable QFT.

    In TGD framework it is however possible that all electroweak Higgses are eaten so that photon would have a very small mass defining physical infrared cutoff. This looks actually unavoidable in TGD framework. Spin 1 bosons are bound states of massless fermion and antifermion with opposite three momenta so that the composite is necessarily massive. Massless fundamental fermions make also possible twistorial description of massivation and allows to get rid of the infrared divergences of massless theories.

    The eating mechanism is much more general and means combination of massless multiplets of various spins to form massive multiplets. Also the higgsinos would suffer the same fate.

    If this theoretically beautiful picture is chosen by Nature, no Higgs will be found. If LHC announces the discovery of Higgs, I have to make a fresh start concerning the physical interpretation of TGD.

    • Ulla says:

      Maybe Higgs comes from some far-away island in a virtual Sea? :)

      Also the Ricci solitons is much about singularities.

    • Lawrence B. Crowell says:

      If the photon has a small mass it would mean that light from a distant source would exhibit dispersion. We know that ∂^2E – ∂^2E = mE, where E is the electric field, means we have propagators G(x,x’) ~ 1/(k^2 – ω^2 – m^2). So this small mass acts as a “frequency” that changes the linear dispersion. This should be apparent in deep space observations, such as these z = 9 galaxies being found by the HST.

      Even if the Higgs field is composite by some means I suspect it will appear as a scalar field at the lowest energy it is produced. Charged Higgs fields in SUSY is an added complexity, but I think the same should hold there as well.

  7. Philip Gibbs says:

    Today’s morning report confirms the 1/fb milestone, but expect a celebration when they have 1/fb for 2011 alone and more when the experiments have 1/fb recorded

    Another interesting note in the report is that they may push up bunch intensity a little. They can’t yet increase bunch number further because of RF power limits.

    • Anon Amateur says:

      Phil,

      I believe this 1/fb you are celebrating is in total luminosity, but not entirely stable luminosity. It includes collisions generated while in Adjust and other modes. You’ve commented in the past about the curious disconnect between your number and other sources. I believe this (as well as lag time on their part) is the cause of the difference you see.

      Hitting 1/fb of delivered stable luminosity will be another significant milestone. I believe this is what is being tracked on other blogs, such as T. Dorigo.

      And for other amateur readers such as myself, it is a third number that actually describes the volume of data available for analysis. Each experiment tracks it’s own recorded luminosity. If the experiments were not listening at the time the luminosity was delivered, it’s like a tree with one hand clapping in a forest… or something. :)

    • Philip Gibbs says:

      You can add the 926.88/pb on TD’s plot to the 29.20/pb delivered in yesterday’s run (fill 1867) that ended at a later time plus the 47.03/pb from last year and you get 1003.11/pb for yesterday evening. These may or may not include non-stable-beams data but it was what TD was looking at.

      Alternatively you can use the updated version of the plot at https://twiki.cern.ch/twiki/bin/view/CMSPublic/LumiPublicResults that is timestamped from early this morning with 959.85/pb and just add the 47.03/pb from 2010 to that giving slightly more.

      As I write this there is another 40.20/pb for CMS from today’s long run, so CMS has now passed the 1/fb mark for 2011 data alone.

      I am not so sure about ATLAS because they had made more adjustments and the morning meeting plot did seem to suggest they needed numbers from outside stable beams to meet the target, but with another 40/pb today they will certainly be there now without any qualifications.

      Using the numbers from the plots on the stats page at https://lhc-statistics.web.cern.ch/LHC-Statistics/ would have left you a few /pb short last night but I was not trusting those. Let’s face it, none of the numbers are that exact, but whatever numbers you use for total delivered all time, they were all well past 1/fb by noon today.

      I agree the recorded data is more important for the experiments and results but the beam operations groups usually celebrate based on delivered numbers. I think they are watching the total for 2011 alone and depending on what numbers they are looking at they may still be 10/pb short. If they keep this fill going for a few more hours they will flag it on the status I bet.

      • algernon says:

        ATLAS currently claims 958/pb recorded on their website (2010+2011. updated before the last fill).

        As I’m writing they’re crossing the 42/pb mark on fill #1868 and that would make it for recorded lumi too, though I’m not sure whether the vistar reports recorded or delivered lumi.
        In the latter case, we’d still be very very close.

        So you got it, 1/fb recorded as of June 14, amazing.
        (not sure why they didn’t include recorded 2010 data in some of their recent papers, though.)

      • carla says:

        I make it another 45/pb *delivered* to pass the 1/fb *recorded* for 2011. So celebrations and another slap on the back for the LHC team from General Rolf-Dieter Heuer sometime Wednesday, I guess.

        I don’t see any point messing around with the current setup if their goal is to provide data for the summer conferences. They haven’t managed to dump after a programmed length of time and them seaminglessly moving onto the next fill. Shouldn’t that be their main goal?

      • Philip Gibbs says:

        The CMS plot was showing the 1/fb mark yesterday and with this latest run even the LHC-statistic page will show 1/fb for 2011. If they had included the 26/pb from missing fill 1745 they could have celebrated much sooner with the rest of us :)

  8. Ervin Goldfain says:

    Phil,

    I wish to make a couple of comments here:

    1) There are indeed Higgs-less models that have been advanced over the years. Some are published in peer-reviewed journals and some posted on arXiv, viXra or debated in various physics blogs.Hopefully LHC will shed light on this issue in the not-so-distant future.

    2) I thought mud-slinging is not encouraged on your blog. Maybe I was wrong. It looks like some commentators still play the blame game. Hostility has nothing to do with science matters.

    Cheers,

    Ervin

    • Philip Gibbs says:

      1) I know there are Higgs-less models and they could be right. I was just interested in what Kea’s version of the theory was because she keeps mentioning the idea without referring us back to her work.

      2) A bit of controversy, provocation and argument is fine so long as it leads to an interesting discussion. I delete only as a last resort when the thread degenerates too far.

    • carla says:

      @Leo Vuyk your profile says you’re an architect so I’m a little lost as to how you can possibly say anything about “what is wrong with physics” until you’ve got a PhD in theoretical physics. What do you know about Lagrangians and gauge invariance in particle physics for example?

      • Leo Vuyk says:

        Thanks Carla,
        I agree that my action has the sound of blasphemy.

        However, I have been assured by mathematicians , that for the simple Rotational form changing freedom of the ring shaped new massless Higgs particle I proposed, the Math is not available and has to be invented.
        Let alone that my form models for ( click-on) combinations of Fermions and Gluons into complex quarks can be described.
        The result was that I did research on the possibility for Function Follows Form in Quantum mechanics resulting in my Quantum- FFF model..

        http://vixra.org/author/Leo_Vuyk

        Consequently I tried to interprete questions made by Smolin,.Bell and Bohm.
        That’s all.

      • carla says:

        @Leo I’m questioning your competence to criticize physics, not the right to criticize. “What is wrong with physics” has the air of a deluded personality. If you took a more humble approach such as “It’s fun to make up physical theories” then people like myself wouldn’t find it so irritating. On the other hand, viXra.org is for people not competent enough to publish on arXiv.org so you certainly have a right to link to your theory from here.

  9. Lawrence B. Crowell says:

    In this discussion on the Higgs field I notice there appears the word “believe,” which is probably not the best word to use here. Nobody believes in the Higgs field, where this “belief” idea might come from Lederman’s coining of the term “God Particle” to describe the Higgs.

    The Higgs field is a particle physics version of a range of phase transition physics from the Curie point to superconductivity. The locking of a gauge freedom in symmetry breaking is similar to breaking of QED in superconductivity. The theory is generically similar to the Landau-Ginsburg potential physics employed in condensed matter physics. This type of phenomenology appears in a number of guises in physics, and it should not be that surprising to think it might occur in particle physics. As a result this is a reasonable hypothesis to work on and to test in accelerator experiments.

    The Higgs field might turn out to be an emergent process, where it could be composed of fermions of some nature. There are dynamical symmetry breaking theories of this nature or related form. In that sense I can consider the prospect the Higgs field as not fundamental. I would find it rather surprising if there should turn out to be no signature of a Higgs or Higgs-like phenomenology in TeV physics.

    • Philip Gibbs says:

      The word “believe” is not reserved for religious faith, nor does it imply an absolute belief beyond reason. You can believe something because you find the scientific evidence for it to be rationally convincing. Scientists are starting to avoid the word because some people say science is like religion and using the word “believe” seems to confirm that, but only to people who don’t understand the literal meaning of the word or who lack the ability to reason logically. Unfortunately there are enough people in that category (they dont read this blog of course) that it probably is better to avoid the word.

      • Lawrence B. Crowell says:

        That is in part my point. The word belief had a broader meaning in the past, but the word is far too wrapped up in matters of faith.

  10. Alejandro Rivero says:

    Let me explain that my question about SUGRA was in good intention. I still hope that all the elementary spectrum will fit in a single supermultiplet. The expectations are raised, respective to 30 years ago, because now the neutrinos are massive, so it is reasonable to account for them 4 degrees of freedom each, instead of 2 as in the traditional standard model. With this account, the total SSM, susy but higgs-agnostic Standard Model, should be naively a 120+120, but it is a fact of representation theory that each massive bosons in a N=1 supermultiplet asks for another chiral 1/2 supermultiplet to be added, and then, having three massive bosons, we need at least a 126+126. Such is the SSM, and now you can choose either to complete to the MSSM, a 128+128 it is, or to add a graviton+gravitino and get again a 128+128, excapt that then it is a SUGRA one.

    • Lawrence B. Crowell says:

      The decomposition E_8 — > SO(16)x128 contains the spinor of SO*(16) ~ spin(16) which contain the 28 monopole charge plus the dual 28 “magnetic” monopole charges, or NUT charges, 2 mass scalars and 70 scalar of N = 8 SUGRA. The complex spinor realization indicates the split form E_{8(8)} is decomposed into spin(16)(x)128, here (x) means otime, and is equivalent to SO(16,C) , which is the corresponding group by the Konstant-Sekiguchi (KS) which acts on 128 . The spin(16) ~ SO(16,C) is the corresponding n-partite entanglement SLOCC (stochastic local operations & classical communications) group for the maximal compact subgroup decomposition of the exceptional group. In this way a 4-partite entanglements in a set of 8 qubits has a correspondence with a “heterotic black hole.”

      • Ulla says:

        Can you tell something also about heterotic E8 strings, and the asymmetric aspect of them.

      • Lawrence B. Crowell says:

        The E_8 has mcs SO(16)x128 and so the E_8xE_8 string states can sit in SO(32). This is a sort of “map,” but there are open questions. This is the closed string which has a correspondence by M-theory is the IIB string.

  11. Emergent Higgs is of course possible and also emergent gauge bosons. In TGD framework all bosons reduce to composites of fermion-antifermion bound states assignable to light.like throats of wormhole contacts. All these
    Higgses can end up to longitudinal polarizations of otherwise massless particles.

    • Lawrence B. Crowell says:

      To Matti & Jal,

      Let me assume the Higgs field is composite. If it is a neutral Higgs scalar it might indeed be composed of fermion-antifermion pairs. The charged Higgs is a more complicated matter. Maybe the Higgs boson is a T-quark condensate. Now let us suppose we give the Higgs vacuum enough energy to pull this composite particle out of the vaccum. We are at a scale where we are just beginning to observe the particle. It might be analogous to Rutherford’s experiment which found the nucleus, but which gives no details as yet. The first ideas of an atom were similar to thinking of billiard balls — no structure was apparent and the atom, or nucleus in the case of Rutherford, was just a “ball.” I suspect much the same would hold for the Higgs field, where our first measurements will be of a scalar field.

      The TGD idea seems to bring up worm holes a lot. This I have found to be somewhat curious. In the above post I wrote I indicate there are 28 NUT-charges. The Taub-NUT spacetime is similar to a black hole, but where time replaces the radial coordinate. This spacetime is analogous to the Dirac monopole string. If it is “bolted” onto a spacetime, or a D-brane, it can be a source of a NUT charge on a brane. Maybe in that sense there can be something similar to a wormhole at work in the universe.

      • Ulla says:

        Remark: A ‘wormhole’ is also understood as a chemical bonding. There are many of them.

      • Lawrence B. Crowell says:

        I never heard of a chemical bond referred to as a wormhole. I don’t think that is what Matti is referring to. The use of the word “throat” suggests a spacetime configuraiton.

      • The trick here, the missing ingredient of compositeness, is that such a massless boson will be part of a _chiral_ supermultiplet, and then how do you expect it to couple either with electromagnetism or with colour?

      • Lawrence B. Crowell says:

        The standard SM production of a Higgs would be for two gluons to emit a Z particle apiece or a Z^+ and Z^- particle. This results in Z + Z — > H or W^+ + W^- — > H. An alternative approach would be if the gluons product a T T-bar pair and there is a T + T-bar interaction which goes into the Higgs. However, this last mechanism might be more subtle with a 4-fermion interaction similar to a BCS Cooper-pairing. In this case there is some color locking which plays the role of the Cooper Pairing, and the resulting Higgs particle is similar to a Cooper pair of electrons.

      • Ulla says:

        A chemical bond is indeed a spacetime change. Excitation of atoms can change the spacetime quite a lot.

  12. jal says:

    I am an interested amateur.
    No one is making the reference that particles/jets are emergent from a Perfect Liquid from which the properties are still unknown and are being determined.

    Lawrence B. Crowell Says:

    “The Higgs field might turn out to be an emergent process”

    What properties would the Perfect Liquid have for an Emergent Higgs, etc.?

  13. To Lawrence and Ulla:

    wormhole contacts do not correspond to chemical bonds. I try to explain.

    In TGD space-time is extremely complex many-sheeted 4-D surface: this in all length scales. One has large number of space-time sheets roughly parallel and with distance of order 10^4 Planck lengths CP_2 size. Stack of 3-branes might be a linguistic picture more familiar to Lawrence.

    The sheets can touch here and there. Actually this is highly probable. This means formation of a wormhole contact. It has **Eulidian** signature of metric: this is something which I want to write with bold and underline! Euclidian signature makes sense since Poincare invariance is realized at imbedding space level. Lawrence likes dualities and the descriptions of the theory based on either the Euclidian regions (Feynman graphs with lines replaced with orbits of 3-D surfaces) or in terms of the Minkowskian regions between them are dual: this is analogy for QFT and its Wick rotation.

    A simple model for the contact is as a piece of CP_2 type vacuum extremal which touches both space-time sheets (topological sum is the term used by mathematicians for touching). One can also make more complex construction by drilling throats with genus 1,2,… to both Minkowskian space-time sheets and connecting with a piece of CP_2 type vacuum extremal (slightly deformed of course).

    At both Minkowskian sheets there is a 3-D surface at which induced metric changes signature from Minkowskian to Euclidian. This surface has degenerate 4-metric and 3-metric and is light-like -like an orbit of massless photon which is actually 2-surface than point like particle. I call this region wormhole throat. It enjoys generalized conformal symmetries by its light-likeness implying metric 2-dimensionality and TGD reduces to almost topological QFT since Kahler action reduces for preferred extremals to Chern-Simons at these surfaces.

    This throat is carrier of elementary particle quantum numbers, in particular fermion and antifermion quantum numbers. The simplest guess is that bosons and their superpartners are constructed by adding to both throats fermions and antifermions. It turns out that this is not quite yet the story: one must have pairs of these contacts since both throats carry magnetic homological magnetic charge and the charges must compensate. Also the screening of weak forces can be understood if pairs are used: the second throat pair carries only neutrino and antineutrino screening the net weak isospin.

    Free fermions and their super partners. are obtained by gluing just single CP_2 type vacuum extremal to Minkowskian space-time sheet. They can also
    touch second space-time sheet but now second throat does not carry fermion number. Again screening of magnetic charges forces pair of these objects.

    Amusingly, physical particles are very stringlike objects albeit 3-D, which should make string enthusiasts very happy;-)! Stringy description indeed emerges in finite measurement resolution also at mathematical level in very precise sense. Wormhole throats are replaced effectively by discrete braids of points carrying fermion number and purely bosonic quantum numbers and the magnetic flux tubes are replaced by string world sheets connecting the braid strands at different wormhole throats.

    • Lawrence B. Crowell says:

      Well you might want to see if you can get a U-duality theory or some composite of S & T dualities there. I will say in some ways I have difficulties in seeing some aspects of what you have been proposing. The CP^n structures might have some relevance, such as CP^3 in T-space, with some current work that is going on, such as the mini-revolution in twistor space Witten kicked off a few years back.

      In the string paradigm particles are open string attached to a D-brane which target maps to spacetime. It might be that strings on a small scale are indeed “composite,” or they might be in some cases Taub-NUT spacetime that are bolted onto branes. Of course such a brane would have NUT charges. The T-NUT space is similar to the Dirac monopole string, so maybe strings on branes have Chan-Paton factors which correspond to NUT monopole “gravi-magnetic” charges. Strings which connect branes would then mean there are isolated NUT charges on a brane. I am not sure how to physically interpret that.

      LC

  14. Luboš Motl says:

    Dear Phil, I just randomly ran onto a paper that I didn’t previously read – just the abstract, assuming it was empty:

    http://arxiv.org/PS_cache/arxiv/pdf/1103/1103.6208v1.pdf

    Do you see the 3-sigma excess of the dileptons at 265 GeV on Figure 1? It’s kind of fun. I think that papers should put a summary of their 3-sigma excesses at some visible place.

    • Alejandro Rivero says:

      It could be funny to have an statistics of papers with 2 and 3 sigma excess, just to see if they fit to a gaussian distribution :-D

    • Philip Gibbs says:

      I’m not sure that this is really three sigma if you take into account the systematic uncertainty shown by the faint yellow areas (I think), but I have not seen that plot updated.

      What did you make of the latest ATLAS conference note https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/CONFNOTES/ATLAS-CONF-2011-090/ ? Does it exclude more parameter space?

      • Luboš Motl says:

        Dear Phil, for the most relevant CMSSM and MSUGRA, the answer is actually No. Despite quintupling the data, it has the same constraints as the previous paper based on the 2010 data. It’s because the 2010 paper had a deficit of events and the deficit is gone now, so the non-improvement of the bounds is nothing to be thrilled about.

  15. Ervin Goldfain says:

    Phil,

    It is unrelated to this post but deserves (at least) a kudos note:

    …the number of viXra submissions has gone over 2000…

    Congratulations for a job well-done!

    Cheers,

    Ervin

  16. Bill K says:

    (Sorry, things are getting too narrow up there!…)

    “The standard SM production of a Higgs would be for two gluons to emit a Z particle apiece or a Z^+ and Z^- particle. This results in Z + Z — > H or W^+ + W^- — > H. An alternative approach would be if the gluons product a T T-bar pair and there is a T + T-bar interaction which goes into the Higgs.”

    I’m not sure about the first part, since Z’s are neutral. And the t t-bar mode won’t happen if the Higgs lies within the usually quoted mass range. The leading Higgs production, I believe, comes from b b-bar.

  17. Dear Lawrence,

    I used the comparison with branes just to give something which might be familiar. TGD is not string theory. If you try to understand TGD in string theory framework you get totally misled and the outcome is complete nonsense with branes.

    If you want to understand the difference between TGD and string models/H-theory at sugra level look

    http://bolvan.ph.utexas.edu/~vadim/Classes/01f/396T/table.pdf

    which gives rough overview about basic fields of sugras in various dimensions and also summarizes the type of spinors used in various dimensions.

    *As you know well, M-theory corresponds to D=11 and N=1 SUSY with Majorana spinors. TGD to D=8 and N=2 SUSY with Dirac spinors: there is no inherent need for Majorana spinors in super-symmetry: this fact is of utmost importance forgotten when the M-theory became in fashion. Theoretical physics is 99 per cent of “folk wisdom” and the outcome is tragedies like this. Always something very very important tends to be forgotten as the tsunami of fashion sweeps out most intelligent life forms.

    *Non-Majorana SUSY allows to have separate conservation of quark and lepton numbers among other things. This is enormous difference with respect to MSSM and M-theory inspired models. Already now the results from LHC have almost excluded SUSY in Majorana sense.

    TGD has hitherto survived: in particular the explanation of muon magnetic moment anomaly has not been lost like in MSSM. Basic prediction is that super-partners for the least broken SUSY are obtained by adding to the state either right-handed neutrino or antineutrino. R-parity is broken by massivation of neutrinos implying the mixin f M^4 chiralities so that these states decay to particle and neutrino. This will serve as a unique signature of TGD SUSY.

    Some additional comments relating to TGD-M-theory relationship.

    *Imbedding space (11-D target space in M-theory) is not dynamical in TGD and is fixed by the existence of the geometry of “world of all classical worlds”-analog of loop space but for 3-surfaces) requiring infinite dimensional symmetries. Therefore there is no landscape.

    *There are no branes, just the basic 3-D objects and their 4-D orbits plus strong form of holography implied by general coordinate invariance.

    *And most importantly, TGD produces standard model symmetries from its very definition -not as input by hand but from extremely general principles-. TGD is also able to predict! And even more, it predicts correctly;-). If Witten had proposed TGD for say 20 years ago, the physics today would look totally different;-).

    • Lawrence B. Crowell says:

      Thanks for the tutorial. I am fairly aware of the SUSY and SUGRA theories. With regards to your TGD idea there are a couple of possibilities. The one is the twisted M^4xCP^2 seems to suggest something like a boson-fermion structure similar to anyonic physics. The other is the use of number theory is suggestive as a way of counting microstates. P-adic number theory and modular forms are used in the derivation of the integer partition.

  18. carla says:

    There’s now a press release from CERN June 17th stating that LHC achieves 2011 milestone http://public.web.cern.ch/press/pressreleases/Releases2011/List.html

  19. carla says:

    A bad week for the LHC with the 3 days lost over the cryogenics and other problems so only 50/pb has been collected. Fingers crossed with the 1236 bunches and breaking the 50/pb for one fill tonight.

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