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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeOct 16th 2018

    am starting some minimum here. Have been trying to read up on this topic. This will likely become huge towards beginning of next year

    v1, current

    • CommentRowNumber2.
    • CommentAuthorDavidRoberts
    • CommentTimeOct 16th 2018
    • (edited Oct 16th 2018)

    Huge for your work, or huge for external reasons, or no comment?

    Edit: oh, I guess there will some CERN announcement on certain results around then (and presumably hundreds of theory papers shortly afterwards proposing solutions :-P)

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeOct 16th 2018

    Didn’t mean to be cryptic, sorry. Am writing from mostly offline family vacation.

    If the Run 2 data analysis of the B meson decay experiments at the LHC confirms the Run 1 data, which seems rather likely, it is apparently clear already that the further data will serve to push the statistical significance of the observed flavour anomaly, which currently is around 3 sigma (= heads up but let’s double-check) to well over 5 sigma (= discovery, call the press), which would make it the first detection of genuinely “new physics” at the LHC which the hep community is longing for so badly.

    Besides the new particle hiding here, it may be of interest for further development of the field that the effect comes not from the traditional direct detection scattering experiments, but from “precision measurement” of anomalies in comparatively low energy decays which reveal high energy particles in the form of “virtual” intermediate processes. This approach towards hep phenomenology (virtual high energy particles seen indirectly by precision measurement of low energy processes) may be the future of hep experiments beyond LHC.

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeOct 27th 2018

    added more references

    diff, v2, current

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeDec 30th 2018

    added more references and explicit pointers to the statement of an effect at around 4σ4 \sigma confidence

    diff, v7, current

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTimeJan 1st 2019

    added some graphics

    diff, v8, current

    • CommentRowNumber7.
    • CommentAuthorRichard Williamson
    • CommentTimeJan 1st 2019
    • (edited Jan 1st 2019)

    It doesn’t really matter, but apparently use of the HTML <center> tag is deprecated in HTML 5, so I replaced it with use of the new LaTeX centring syntax :-).

    • CommentRowNumber8.
    • CommentAuthorUrs
    • CommentTimeJan 1st 2019

    I see, thanks.

    • CommentRowNumber9.
    • CommentAuthorUrs
    • CommentTimeJan 16th 2019

    added pointer on possible explanation via leptoquarks (here)

    diff, v13, current

    • CommentRowNumber10.
    • CommentAuthorUrs
    • CommentTimeJan 20th 2019

    added pointer to this nice set of slides

    • Francesca Dordei, Lepton flavour universality at LHCb, August 2018 (cern:2634813, pdf)

    diff, v17, current

    • CommentRowNumber11.
    • CommentAuthorUrs
    • CommentTimeJan 22nd 2019
    • (edited Jan 22nd 2019)

    added a bunch of further pointers.

    references by Andreas Crivellin stand out. In Crivellin 18, published one month ago (, the author speaks of “compelling evidence for New Physics” (p. 2)

    diff, v19, current

    • CommentRowNumber12.
    • CommentAuthorUrs
    • CommentTimeJan 23rd 2019

    clarified the distinction between the claimed \gt 5 \sigma$ significance of all decay channels jointly, over that of each channel separately

    diff, v20, current

    • CommentRowNumber13.
    • CommentAuthorUrs
    • CommentTimeJan 23rd 2019
    • (edited Jan 23rd 2019)

    added here the two tables by Lyons and Dorigo, kindly pointed out by David C., which argue that the detection-threshold for the significance of the flavour anomaly is at 3σ3 \sigma and hence a) much lower than the conventional 5σ5 \sigma and b) long exceeded by the experimental signal.

    diff, v21, current

    • CommentRowNumber14.
    • CommentAuthorUrs
    • CommentTimeJan 23rd 2019

    added pointer to

    • Jacky Kumar, David London, New physics in bse +e b \to s e^+ e^-? (arXiv:1901.04516)

    from a few days ago.

    They now quote a statistical significance of up to 6σ6 \sigma, but I didn’t figure out where exactly they take that value from.

    diff, v22, current

    • CommentRowNumber15.
    • CommentAuthorUrs
    • CommentTimeJan 23rd 2019
    • (edited Jan 23rd 2019)

    The recent arxiv:1901.04761 seems to see the significance at 5.8 sigma (though I admit I don’t know what that “pull”-terminology is saying, here and elsewhere?) and tries to explain it with a dark matter particle. Somehow.

    • CommentRowNumber16.
    • CommentAuthorUrs
    • CommentTimeJan 25th 2019
    • (edited Jan 25th 2019)

    Today’s arXiv:1901.08290 sees the anomaly at 4sigma and suggest to explain it by an “extended Higgs sector” and right-handed neutrinos.

    • CommentRowNumber17.
    • CommentAuthorUrs
    • CommentTimeJan 25th 2019

    and then there is today’s

    • Domagoj Leljak, Blazenka Melic, Monalisa Patra, On lepton flavour universality in semileptonic B cη c,J/ψB_c \to \eta_c, J/\psi decays (arXiv:1901.08368)

    I don’t understand yet really the point they are making, but they point to

    • Monika Blanke, Andreas Crivellin, Stefan de Boer, Teppei Kitahara, Marta Moscati, Ulrich Nierste, Ivan Nišandžić, Impact of polarization observables and B cτνB_c \to \tau \nu on new physics explanations of the bcτνb \to c \tau \nu anomaly (arXiv:1811.09603)

    which I had missed earlier. This has some informative graphics from p. 10 on

    diff, v25, current

    • CommentRowNumber18.
    • CommentAuthorUrs
    • CommentTimeJan 28th 2019

    Today in arXiv:1901.06380 review of the flavour anomalies as seen by the BELLE experiment, at 3.78 sigma.

    • CommentRowNumber19.
    • CommentAuthorUrs
    • CommentTimeJan 31st 2019

    Today’s arXiv:1901.10484 claims that if one assumes the putative leptoquark to respect certain residual abelian flavour symmetries of the Yukawa couplings (which apparently is plausible when asking for UV-completion of the model) then not only is the resulting fit to the flavour anomaly data “excellent” but also the remaining choices become very constrained, making the leptoquark explanation of the flavour anomalies “extremely predictive”.

    • CommentRowNumber20.
    • CommentAuthorUrs
    • CommentTimeJan 31st 2019

    also today:

    more analysis of the potential lpetoquark model for flavour anomalies;

    • Michael J. Baker, Javier Fuentes-Martin, Gino Isidori, Matthias König, High-pT Signatures in Vector-Leptoquark Models (arXiv:1901.10480)

    and a replacement from last month on how the same leptoquark that could explain the flavour anomalies might also explain the anomalies seen at the ANITA experiment:

    • Bhavesh Chauhan, Subhendra Mohanty, A common leptoquark solution of flavor and ANITA anomalies (arXiv:1812.00919)

    diff, v34, current

    • CommentRowNumber21.
    • CommentAuthorUrs
    • CommentTimeJan 31st 2019

    and yet one more today: This article

    • Natascia Vignaroli, Seeking leptoquarks in the tt¯t \bar t plus missing energy channel at the high-luminosity LHC (arXiv:1808.10309)

    talks about possible direct detection of the leptoquarks motived by the flavour anomalies

    diff, v34, current

    • CommentRowNumber22.
    • CommentAuthorUrs
    • CommentTimeFeb 5th 2019
    • (edited Feb 5th 2019)

    today in

    • G. D’Ambrosio, A. M. Iyer, F. Piccinini, A.D. Polosa, Confronting BB anomalies with atomic physics (arXiv:1902.00893)

    more investigation of the possibility that the anomalies could be pointing to a Z’-boson

    diff, v36, current

    • CommentRowNumber23.
    • CommentAuthorUrs
    • CommentTimeFeb 7th 2019
    • (edited Feb 7th 2019)

    New measurements by LHCb reported today in (arXiv:1902.02092) for one of the decay channels. It concludes by saying the 2.8sigma discrepancy found earlier by ATLAS in this channel is confirmed, but “with higher precision”

    • CommentRowNumber24.
    • CommentAuthorUrs
    • CommentTimeFeb 7th 2019

    Ah, no, apparently that channel is not a flavour anomaly, but a pentaquark resonance (arXiv:1606.06999)

    • CommentRowNumber25.
    • CommentAuthorUrs
    • CommentTimeFeb 11th 2019

    added pointe to today’s

    • Srimoy Bhattacharya, Aritra Biswas, Zaineb Calcuttawala, Sunando Kumar Patra, An in-depth analysis of bc(s)b \to c(s) semileptonic observables with possible μτ\mu \to \tau mixing (arXiv:1902.02796)

    We thus conclude that the models IV and V, while still incapable of a satisfactory explanation of R(K *) LowR(K^\ast)_{Low}, is not only allowed by the plethora of flavor observables, but also is of high statistical significance, with quite a precise prediction for effective Wilson coefficients, providing a possible path-way for future model builders. High precision experiments inthe coming days will illuminate the map even further.

    diff, v40, current

    • CommentRowNumber26.
    • CommentAuthorUrs
    • CommentTimeFeb 14th 2019

    Today arXiv:1902.04900 sees the effect globally at 5.3 to 5.8 sigma.

    • CommentRowNumber27.
    • CommentAuthorAlizter
    • CommentTimeFeb 14th 2019

    @Urs what sigma was it before?

    • CommentRowNumber28.
    • CommentAuthorUrs
    • CommentTimeFeb 14th 2019

    Have a look at the entry: flavour+anomaly#StatisticalSignificance

    • CommentRowNumber29.
    • CommentAuthorUrs
    • CommentTimeFeb 19th 2019

    added pointer to today’s

    • P. Ko, Takaaki Nomura, Chaehyun Yu, bsμ +μ b \to s \mu^+ \mu^- anomalies and related phenomenology in U(1) B 3x μL μx τL τU(1)_{B_{3-x_\mu L_\mu - x_\tau L_\tau}} flavor gauge models (arXiv:1902.06107)

    with more on the hypothesis that it’s a Z’-boson causing the flavour anomalies

    diff, v42, current

    • CommentRowNumber30.
    • CommentAuthorUrs
    • CommentTimeMar 6th 2019
    • (edited Mar 6th 2019)

    added pointer to today’s

    • Oscar Cata, Thomas Mannel, Linking lepton number violation with BB anomalies (arXiv:1903.01799)

    diff, v45, current

    • CommentRowNumber31.
    • CommentAuthorUrs
    • CommentTimeMar 11th 2019
    • (edited Mar 11th 2019)

    for when the entry becomes editable again, the following should be added:


    presents new measurement results on a polarization observable in B-meson decays, and finds disagreement with the standard model at 1.7 σ\sigma, on top of the global 4σ\sim 4 \sigma of the previous observables

  1. It should become editable some time this evening European time. Apologies for the continued inconvenience.

    • CommentRowNumber33.
    • CommentAuthorUrs
    • CommentTimeMar 11th 2019

    All right, thanks a million!!

  2. Change <img> tags to imagefromfile blocks to make them render, and change a <br\> to use \linebreak.

    diff, v46, current

    • CommentRowNumber35.
    • CommentAuthorUrs
    • CommentTime7 days ago
    • (edited 7 days ago)

    Richard, thanks for looking into this.

    Let me just see if I understand where we are headed. Now it looks a little like I’ll have to incrementally rewrite parts of many nLab entries for them to work again. To be frank, that makes me feel a little overwhelmed. This affects many dozens of pages, I am afraid, and I don’t even know how to find all those affected.

    And there are more tags in use.

    For instance, just now I wanted to upload my slides to Equivariant Super Homotopy Theory (schreiber), for my talk tomorrow morning. But editing the entry does not work. There is an image there, which you just told me how to work around. But the parser actually complains about the div-tag, which maybe we don’t have a workaround for yet.

    I don’t have any insight into that sanitiser business, and I understand that you have good reasons not to build on that solution. But maybe just for the moment, so that we all have some time to take a step back and think about how to proceed with the security implementation, might it make sense to just implement the sanitiser, say as an intermediate hack? That would, I suppose, make the nnLab work and be secure for the time being, and give us time and leisure to make plans.

    What do you think?

  3. I will disable the stricter checking for the moment, so that you can upload your slides. Just a second, I’ll let you know when it’s done.

    • CommentRowNumber37.
    • CommentAuthorRichard Williamson
    • CommentTime7 days ago
    • (edited 7 days ago)

    Now done, you should now be able to upload your slides. We still have the security level of #1 here in place. The new syntax still works.

  4. Let’s continue the discussion of #35 over at that thread.

    • CommentRowNumber39.
    • CommentAuthorUrs
    • CommentTime7 days ago

    Excellent, thanks!!

    • CommentRowNumber40.
    • CommentAuthorUrs
    • CommentTime6 days ago
    • (edited 6 days ago)

    added pointer to today’s review

    and included a graphics from that article

    diff, v48, current

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