Thursday, July 14, 2016

What if 750 GeV bump disappears?

I have been working for years with M89 hadron physics hypothesis inspired originally by p-adic length scale hypothesis around 1995 and also by strange cosmic ray events (see this). Later I realized that the strange and unexpected findings about the properties of quark gluon plasma could be perhaps understand in terms of M89 hadron physics. This inspired to consider also the possibility that the the candidates for M89 mesons are produced as dark particles having Compton length which is of same order of magnitude as proton Compton length.

If dark variants of particles are produced only at quantum criticality, it might happen that the production of M89 mesons occurs considerably only around critical collision energy for the proton beams at LHC and the bumps could disappear at higher LHC energies. Unfortunately, quantum criticality does not belong to the vocabulary of particle physicists so that I must be ready to tolerate merciless ridicule also in future! This seems to be the universal fate of all who see farther off than others.

I collect here what looks like the quintessence of the comments about M89 hadron physics. I have not edited the old comments and it I cannot exclude the possibility of some small internal inconsistencies.

Some background

Large Hadron Collider May Have Produced New Matter is the title of popular article explaining briefly the surprising findings of LHC made for the first time September 2010. A fascinating possibility is that these events could be seen as a direct signature of brand new hadron physics. I distinguish this new hadron physics using the attribute M89 to distinguish it from ordinary hadron physics assigned to Mersenne prime M107 =2107 -1.

Quark gluon plasma is expected to be generated in high energy heavy ion collisions if QCD is the theory of strong interactions. This would mean that quarks and gluons are de-confined and form a gas of free partons. Something different was however observed already at RHIC: the surprise was the presence of highly correlated pairs of charged particles. The members of pairs tended to move in parallel: either in same or opposite directions.

This forced to give up the description in terms of quark gluon plasma and to introduce what was called color glass condensate. The proposal was that so called color glass condensate, which is liquid with strong correlations between the velocities of nearby particles rather than gas like state in which these correlations are absent, is created: one can imagine that a kind of thin wall of gluons is generated as the highly Lorentz contracted nuclei collide. The liquid like character would explain why pairs tend to move in parallel manner. Why they can move also in antiparallel manner is not obvious to me although I have considered the TGD based view about color glass condensate inspired by the fact that the field equations for preferred extremals are hydrodynamical and it might be possible to model this phase of collision using scaled version of critical cosmology which is unique apart from scaling of the parameter characterizing the duration of this critical period. Later LHC found a similar behavior in heavy ion collisions. The theoretical understanding of the phenomenon is however far from complete.

The real surprise was the observation of similar events in proton proton collisions at LHC: for the first time already at 2010. Lubos Motl wrote a nice posting about this observation. Also I wrote a short comment about the finding. Now the findings have been published: preprint can be found in arXiv. Below is the abstract of the preprint.

Results on two-particle angular correlations for charged particles emitted in pPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV are presented. The analysis uses two million collisions collected with the CMS detector at the LHC. The correlations are studied over a broad range of pseudorapidity η, and full azimuth φ, as a function of charged particle multiplicity and particle transverse momentum, pT. In high-multiplicity events, a long-range (2<|(Δ η| <4), near-side Δ φ approximately 0) structure emerges in the two-particle Δ η-Δ φ correlation functions. This is the first observation of such correlations in proton-nucleus collisions, resembling the ridge-like correlations seen in high-multiplicity pp collisions at s1/2 = 7 TeV and in A on A collisions over a broad range of center-of-mass energies. The correlation strength exhibits a pronounced maximum in the range of pT = 1-1.5 GeV and an approximately linear increase with charged particle multiplicity for high-multiplicity events. These observations are qualitatively similar to those in pp collisions when selecting the same observed particle multiplicity, while the overall strength of the correlations is significantly larger in pPb collisions.

Second highly attractive explanation discussed by Lubos Motl is in terms of production of string like objects. In this case the momenta of the decay products tend to be parallel to the strings since the constituents giving rise to ultimate decay products are confined inside 1-dimensional string like object. In this case it is easy to understand the presence of both parallel and antiparallel pairs. If the string is very heavy, a large number of particles would move in collinear manner in opposite directions. Color quark condensate would explain this in terms of hydrodynamical flow.

In TGD framework these string like objects would correspond to color magnetic flux tubes. These flux tubes carrying quark and antiquark at their ends should however make them manifest only in low energy hadron physics serving as a model for hadrons, not at ultrahigh collision energies for protons. Could this mean that these flux tubes correspond to hadrons of M89 hadron physics? M89 hadron physics would be low energy hadron physics since the scaled counterpart of QCD Λ around 200 MeV is about 100 GeV and the scaled counterpart of proton mass is around.5 TeV (scaling is by factor is 512 as ratio of square roots of M89 =289 -1, and M107 ). What would happen in the collision would be the formation of p-adically hot spot at p-adic temperature T=1 for M89 .

For instance, the resulting M89 pion would have mass around 67.5 GeV if a naive scaling of ordinary pion mass holds true. p-Adic length scale hypothesis allows power of 21/2 as a multiplicative factor and one would obtain something like 135 GeV for factor 2: Fermi telescope has provided evidence for this kind particle although it might be that systematic error is involved (see the nice posting of Resonaance). The signal has been also observed by Fermi telescope for the Earth limb data where there should be none if dark matter in galactic center is the source of the events. I have proposed that M89 hadrons - in particular M89 pions - are also produced in the collisions of ultrahigh energy cosmic rays with the nuclei of the atmosphere: maybe this could explain also the Earth limb data. Recall that my first erratic interpretation for 125 GeV Higgs like state was as M89 pion and only later emerged the interpretation of Fermi events in terms of M89 pion.

Could M89 hadrons give rise to the events?

One can consider a more concrete model for the situation.

  1. The first picture is that M89 color magnetic flubes tubes are created between the colliding protons and have length and thickness which is 512 shorter than that of ordinary hadronic color flux tubes and therefore also 512 times higher energy. The energy of colliding protons would be partially transformed to that of M89 mesons. This process should occur above critical collision energy Ecr(p)=512 mp∼ .5 TeV and perhaps already above Ecr(p)= m(pi89)=67.5 GeV. One can worry about the small geometric size of M89 mesons: is it really possible to transfer of energy of protons consisting of quarks to a scale shorter by factor 1/512 or does this process occur at quark level and doesn't one encounter the same problem here? This problem leads to second picture.

  2. M89 mesons could be dark so that their size is same as the size of protons: this could make possible a collective transfer of collision energy in the scale of entire proton to that of dark M89 mesons transforming later to much smaller ordinary M89 mesons. If this is the size the value heff/h=512 is favourable.

  3. The proposal (see this) is that dark phases of matter are generated at quantum criticality: does quantum criticality mean now that dark M89 mesons are created only near the threshold for the process but not at higher collision energies? If so, the production of M89 mesons would be observed only near energies Ecr assignable to proton-proton cm and quark-quark cm. For constituent quarks identifiable as current quark plus its magnetic body, the masses would be roughly mp/3 and one would have Ecr(q)=3 Ecr(q) (note that the masses of u and d current quarks are the scale of 5-20 MeV so thatcolor magnetic energy dominates baryon mass).

  4. This brings in mind leptohadron model (see this) explaining the reported production of mesonlike states in heavy ion collisions. These states had mass slightly larger than twice the mass of electron and they decayed to electron-positron pair. The production was observed only in the vicinity of Coulomb wall of order MeV, the mass of electro-pion. The explanation is in terms of color excited electrons forming pion like bound state. If color excited leptons are light, the decay widths of weak bosons are predicted to be too large. If the produced states are dark, one circumvents this problem. Quantum criticality corresponds to Coulomb wall and explains why the production occurs around it.

    In the recent case quantum criticality could mean the threshold for production of M89 mesons. The bad news is that quantum criticality could mean that M89 mesons are not produced at higher LHC energies so that the observed bumps assignable to M89 would suffer the usual fate of the bump. Since quantum criticality does not belong to the conceptual repertoire of particle physicists, one cannot expect that the notion of M89 hadron would be accepted easily by the community.

Further indications for M89 hadron physics

During last years several indications for the new physics suggested by TGD have emerged. Recently the first LHC Run 2 results were announced and there was a live webcast (see this).

  1. The great news was the evidence for a two photon bump at 750 GeV about which there had been rumors. Lubos told earlier about indications for diphoton bump around 700 GeV. If the scaling factor is the naive 512 so that M89 pion would have mass about 70 GeV, there are several meson candidates. The inspection of the experimental meson spectrum (see this) shows that there is quite many resonances with desired quantum numbers. The scaled up variants of neutral scalar mesons η(1405) and η(1475) consisting of quark pair would have mases 719.4 GeV and 755.2 GeV and could explain both 700 GeV and 750 bump. There are also neutral exotic mesons which cannot be quark pairs but pairs of quark pairs (see this) f0(400), f0(980), f2(1270), f0(1370), f0(1500), f2(1430), f2(1565), f2(1640), f?(1710) (the subscript tells the total spin and the number inside brackets gives mass in MeVs) would have naively scaled up masses 204.8, 501.8, 650.2, 701.4, 768.0, 732.2, 801.3, 840.0, 875.5 GeV. Thus f0 meson consisting of two quark pairs would be also a marginal candidate. The charged exotic meson a0(1450) scales up to 742.4 GeV state.

  2. There is a further mystery involved. Matt Strassler (see this) emphasizes the mysterious finding fact that the possible particle behind the bump does not seem to decay to jets: only 2-photon state is observed. Situation might of course change when data are analyzed. Jester (see this) in fact reports that 1 sigma evidence for Zγ decays has been observed around 730 GeV. The best fit to the bump has rather large width, which means that there must be many other decay channels than digamma channels. If they are strong as for TGD model, one can argue that they should have been observed.

    As if the particle would not have any direct decay modes to quarks, gluons and other elementary particles. If the particle consists of quarks of M89 hadron physics it could decay to mesons of M89 hadron physics but we cannot directly observe them. Is this enough to explain the absence of ordinary hadron jets: are M89 jets somehow smoothed out as they decay to ordinary hadrons? Or is something more required? Could they decay to M89 hadrons leaking out from the reactor volume before a transition to ordinary hadrons?

    Or could a more mundane explanation work? Could 750 GeV states be dark M89 eta mesons decaying only via digamma annihilation to ordinary particles be in question? For ordinary pion the decays to gamma pairs dominate over the decays to electron pairs. Decays of ordinary pions to lepton or quark pairs must occur either by coupling to axial weak current or via electromagnetic instanton term coupling pseudo-scalar state to two photon state. The axial current channel is extremely slow due to the large mass of ordinary weak bosons but I have proposed that variants of weak bosons with p-adically scaled down masses are involved with the decays recently called X bosons (see this) and perhaps also with the decays of ordinary pion to lepton pairs). Pseudoscalar can also decay to virtual gamma pair decaying to fermion pair and for this the rate is much lower than for the decay to gamma pair. This would be the case also for M89 mesons if the decays to lepton or quark pair occurs via these channels. This might be enough to explain why the decay products are mostly gamma pairs.

  3. Above arguments suggest the production of dark M89 hadrons with heff/h=512 at quantum criticality. The TGD inspired idea that M89 hadrons are produced at RHIC in heavy ion collisions and in proton heavy ion collisions at LHC as dark variants with large value of heff= n× h with scaled up Compton length of order hadron size or even nuclear size conforms with finding that the decay of string like objects identifiable as M89 hadrons in TGD framework explains the unexpected properties of what was expected to be simple quark gluon plasma analogous to blackbody radiation.

    Quantum criticality (see this) suggests that the production of dark M89 mesons (responsible for quantal long range correlations) is significant only near the threshold for their production (the energy transfer would take place in scale of proton to dark M89 meson with size of proton). Note that in TGD inspired biology dark EEG photons would have energies in bio-photon energy range (visible and UV) and would be exactly analogous to dark M89 hadrons. The criticality could correspond to the phase transition from confined to de-confined phase (at criticality confinement with much larger mass but with scaled up Compton wavelength!).

    The bad news is that the rate for the production of M89 mesons with standard value of Planck constant at higher LHC energies could be undetectably small. If this is the case, there is no other way than tolerate the ridicule, and patiently wait that quantum criticality finds its place in the conceptual repertoire of particles physicists. New results about 750 GeV bump will be released at the beginning of August and there are "reliable" rumors that the bump is disappearing. The group led by my finnish colleague Risto Orava (we started as enthusiastic physics students at the same year and were coffee table friends) is scanning for old LHC data for possible evidence for 750 GeV state. If the bump is there but disappears at higher energies, it would provide support for quantum criticality.

  4. Lubos mentions in his posting several excesses, which could be assigned with the above mentioned states. The bump at 750 GeV could correspond to scaled up copy of η(1475) or - less probably - f0(1500). Also the bump structure around 700 GeV for which there are indications (see this) could be explained as a scaled up copy of η(1405) or f0(1370) with mass around 685 GeV. Lubos mentions also a 662 GeV bump (see this). If it turns out that there are several resonances in 700 TeV region (and also elsewhere) then the only reasonable explanation relies on hadron like states since one cannot expect a large number of Higgs like elementary particles. One can of course ask why the exotic states should be seen first.

  5. Remarkably, for the somewhat ad hoc scaling factor 2× 512∼ 103 one does not have any candidates so that the M89 neutral pion should have the naively predicted mass around 67.5 GeV. Old Aleph anomaly > had mass 55 GeV. This anomaly did not survive. I found from my old writings > that Delphi and L3 have also observed 4-jet anomaly with dijet invariant mass about 68 GeV: M89 pion? There is indeed an article about search of charged Higgs bosons in L3 (see this) telling about an excess in csbarτ-νbarτ production identified in terms of H+H- annihilation suggesting charged Higgs mass 68 GeV. TGD based interpretation would in terms of the annihilation of charged M89 pions.

    The gammas in 130-140 GeV range detected by Fermi telescope (see this) were the motivation for assuming that M89 pion has mass twice the naively scaled up mass. The digammas could have been produced in the annihilation of a state with mass 260 GeV. The particle would be the counterpart of the ordinary η meson η(548) with scaled up mass 274 GeV thus decaying to two gammas with energies 137 GeV. An alternative identification of the galactic gamma rays in terms of gamma ray pairs resulting in the annihilation of two dark matter particles nearly at rest. It has been found that this interpretation cannot be correct (see this).

    Also scaled up eta prime should be there. Also an excess in the production of two-jets above 500 GeV dijet mass has been reported (see this) and could relate to the decays of η'(958) with scaled up mass of 479 GeV! Also digamma bump should be detected.

  6. What about M89 kaon? It would have scaled up mass 250 GeV and could also decay to digamma. There are indications for a Higgs like state with mass of 250 GeV from ATLAS (see this! It would decay to 125 GeV photons - the energy happens to be equal to Higgs mass. There are thus indications for both pion, kaon, all three scaled up η mesons and kaon and η' with predicted masses! The low lying M89 meson spectroscopy could have been already seen!

  7. Lubos mentions (see this) also indications for 285 GeV bump decaying to gamma pair. The mass of the eta meson of ordinary hadron physics is .547 GeV and the scaling of eta mass by factor 512 gives 280.5 GeV : the error is less than 2 per cent.

  8. Lubos tells (see this) about 3 sigma bump at 1.650 TeV assigned to Kaluza-Klein graviton in the search for Higgs pairs hh decaying to bbbar +bbbar>. Kaluza-Klein gravitons are rather exotic creatures and in absence of any other support for superstring model they are not the first candidate coming into my mind. I do not know how strong the evidence for spin 2 is but I dare to consider the possibility of spin 1 and ask whether M89 hadron physics could allow an identification for this bump.

    1. Very naively the scaled up J/Psi of the ordinary M107 hadron physics having spin J=1 and mass equal to 3.1 GeV would have 512 times higher mass 1.585 TeV: error is about 4 per cent. The effective action would be based on gradient coupling similar in form to Zhh coupling. The decays of scaled up Ψ/J could take place via hh → bbbar+bbbar also now.

    2. This scaling might be too naive: the quarks of M89 hadron physis might be same as those of ordinary hadron physics so that only the color magnetic energy would be scaled up by factor 512. c quark mass is equal 1.29 GeV so that the magnetic energy of ordinary J/Psi would be equal to .52 GeV. If so, M89 version of J/Psi would have mass of only 269 GeV. Lubos tells also about evidence for a 2 sigma bump at 280 GeV identified as CP odd Higgs - this identification of course reflects the dream of Lubos about standard SUSY at LHC energies. However, the scaling of η meson mass 547.8 MeV by 512 gives 280.4 GeV so that the interpretation as η meson proposed already earlier is convincing. The naive scaling might be the correct thing to do also for mesons containing heavier quarks.

  9. Lubos (see this) also tells about an excess (I am grateful for Lubos for keeping book about the bumps: this helps enormously), which could have interpretation as the lightest M89 vector meson - ρ89 or ω89. Mass is the predicted correctly with 5 per cent accuracy by the familiar p-adic scaling argument: multiply the mass of ordinary meson with 512.

    This 375 GeV excess might indeed represent the lightest vector meson of M89 hadron physics. ρ and ω of standard hadron physics have mass 775 MeV and the scaled up mass is about 397 GeV, which is about 5 per cent heavier than the mass of Zγ excess.

    The decay ρ→ Z+γ describable at quark level via quark exchange diagram involving emission of Z and γ. The effective action would be proportional to Tr(ρ*γ*Z), where the product and trace are for antisymmetric field tensors. This kind effective action should describe also the decay to gamma pair. By angular momentum conservation the photons of gamma pairs should be in relative L=1 state. Since Z is relativistic, L=1 is expected to be favored also for Z+γ final state. Professional could immediately tell whether this is correct view. Similar argument applies to the decay of ω which is isospin singlet. For charged ρ also decays to Wγ and WZ are possible. Note that the next lightest vector meson would be K* with mass 892 MeV. K*89 should have mass 457 GeV.

  10. Lubos (see this) also reports that ATLAS sees charged boson excess manifesting via decay to tb in the range 200-600 TeV. Here Lubos takes the artistic freedom to talk about charged Higgs boson excess since Lubos still believes in standard SUSY predicting copies several Higgs doublets. TGD does not allow them. In TGD framework the excess could be due to the presence of charged M89 mesons: pion, kaon, ρ, ω.

  11. A smoking gun evidence would be detection of production of pairs of M89 nucleons with masses predicted by naive scaling to be around 470 GeV. This would give rise to dijets above 940 GeV cm energy with jets having total quantum numbers of ordinary nucleons. Each M89 nucleon consisting of 3 quarks of M89 hadron physics could also transform to ordinary quarks producing 3 ordinary hadron jets.

For background see the article Indications for the new physics predicted by TGD and the chapter New Particle Physics Predicted by TGD: Part I of "p-Adic physics".

For a summary of earlier postings see Latest progress in TGD.


Leo Vuyk said...

Dissappearing or not, MHO says there should be series of diphoton excesses. if they are based on real particle interlocking processes like this: said...

Quantum criticality is something new and hopefully means rehabilitation for many researchers who had the fate of discovering this kind of phenomenon. It appears at critical values of parameters only and if this is not known it is very easy to miss it. Free energy research, cold fusion research, precognition, psychokinesis,...: all those branches of so called pseudoscience. Generation of dark matter as such could be quantum critical phenomenon. This could explain that there has been no progress in its understanding. Problem is here the narrow mindedness of particle phycisists. Condensed matter physicists are talking about quantum criticality.