Scepticism On The Opera Result: Protecting The Establishment ?
    By Tommaso Dorigo | October 11th 2011 07:14 AM | 55 comments | Print | E-mail | Track Comments
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    I am an experimental particle physicist working with the CMS experiment at CERN. In my spare time I play chess, abuse the piano, and aim my dobson...

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    I read with interest and some amusement (on the mouse joke) the piece written here by Sascha Vongehr. I find his arguments wrong and decided to answer him in the comments thread of his post, but my answer got a bit too long and I did not want to hijack a nice discussion that was developing there; plus I found out that what I was writing could be suitable for this blog in its own right. So below I explain what I criticize about his arguments.

    In short, Sascha takes the general scepticism by physicists to the 6-sigma result on superluminal motion found by Opera as an indication of them wanting to "protect the establishment" and the system of POP-science (publish-or-perish), and compares the high significance of that result to one-point-something-sigma effects used in other branches of science to "prove" something. He adds that the 6-sigma Opera result is actually a "confirmation" of the earlier "evidence" by Minos, which found a 1.8-sigma superluminal motion of neutrinos. Here is my reply.

    1. A 1.8-sigma result, in particle physics, is nothing. Sascha should not compare to other fields of science, which are totally different things with different metrics. In clinical studies 1.8 standard deviations may grant a publication (with all the negative side-effects that Sascha correctly highlights), but in HEP nobody even considers it an effect. We test hundreds of quantities, and some always fall in the "two-sigma" bin without there being any effect to worry about. 1.8 sigma effects occur once in 20 trials of the null hypothesis, so they are usually nothing, really. Not the "evidence" that Sascha claims Minos was. One would be ridiculed if one took very seriously such an inconclusive result. The reason is largely based on what I discuss in point 2 below, namely the "degree of belief" of a theory or its falsification.

    2. a 6.0-sigma result, in particle physics, is generally a significant observation of an effect. However, just how much one believes it depends on seventy years of practice in the field, when highly significant results have occasionally turned out to be due to unknown shapes of the probability density functions of the associated measurement errors. All but the most gullible of my colleagues know they should take with a pinch of salt a "significant observation", because we all know that our measurements are complicated and that we are not infallible.

    In the case of the Opera measurement there are a number of things that may have gone wrong, and this alone could have lead anybody to doubt the correctness of the measurement, even if it had been giving v=c. Just as an example, there is a subtraction of the time offset due to the travel time inside a light guide which is 8.5 km long. The travel time of the signal there is 40 microseconds, and this is allegedly known to +- 1 ns, i.e. one part in 40 thousand. Now, that measurement was done in 2007, and since then the refraction index of the light guide might have increased by 0.001+-0.001, adding a 40+-40 ns offset and making the 60-ns effect seen by Opera a insignificant result. [Yes, plastic materials do change their refractive properties in certain cases].

    I am giving this example just to explain how difficult these measurements are. Now, there is however another reason to doubt the correctness of the Opera measurement: indeed, physicists have learned to use the fact that "extraordinary claims need extraordinary evidence". No, it is not the same thing to find the top quark at 6-sigma or find that v>c at 6-sigma. The former was an expected result, the latter was not.

    Personal bias ? Anathema ? No, just risk analysis. We are Bayesians deep within, and we know that if somebody comes by and tells us "there is a fire downstairs" we are less likely to doubt it than if she comes in and tells us "there is a 12-foot spider downstairs".

    We need to remind ourselves that science progresses if we maintain a highly sceptical attitude toward anything we measure or find until we prove it and understand it; neither can be said of the Opera result. Science becomes chaos, instead if we accept any new measurement and its implications, however bold, as a new truth. So being sceptical is the right thing, and Sascha's argument is wrong. The scepticism on the Opera result is not due to physicists wanting to protect the establishment. It is due to their doing their job - requiring more evidence to accept more extraordinary claims.



    You bring up a valid point - but I don't think it really addresses the core of Sascha's post. The main point he was making, as I understand it, is that those who are established in a field will attempt to suppress their rivals through the peer review process. This is just a simple consequence of human nature - people generally want to maximize their own perceived self benefit.

    Thank you for pointing this out. Indeed, he has not grasped the content of my post. I myself doubted the results early and repeatedly and I know, since I am in HEP myself, very well what a sigma in particle physics is.
    Very happy to see this contribution from Tommaso. I also like Krauss' thoughts on this subject: .

    Many bloggers, including one on this blog site, let themselves get carried away in a hype that can only harm science. I believe most of them lack the true physics insight to present a balanced story, others are best descrbed as attention whores.

    Many bloggers, including one on this blog site, let themselves get carried away in a hype that can only harm science ... best descrbed as attention whores
    Maybe Tommaso is overdoing it a bit with hyping every hump on every bump for the Higgs and maybe his desperation for attention, say via trying to smear honey around big name's beards in order to get to venues like the ever worse TED events (admitted - TED is attention w**** territory) leave the good taste domain once in a while, but that you call him names goes too far and I would like to strongly distance myself from such behavior.
    About lack of true insight and a balanced story: You are welcome to learn from my posts. Feel free to ask questions wherever they go over your head.

    Thanks for the offer. If I need any advice on how to act like a clown or how to become an attention w***e, I will not hesitate to contact you. For science related matters I prefer to go to a well-respected scientist like Tommaso.

    Sascha read your comment, as did I, and thought you were saying Tommaso was out for attention - and he was therefore defending him.
    Yes PT, but that was not the only thing he argued about -otherwise his post would be just the thousandth on the beaten-to-death issue.

    He focused the first part of his post on the "knee jerk" reaction of scientists to a result that goes against the established science. It's even in the title...

    An establishment-science cheerleader calling the widely known and deeply problematic issue of publish-or-perish and the major role of peer-review in there a "beaten-to-death issue" is exactly the kind of arrogance that the public increasingly perceives, the very source of their justified distrust of science.
    BTW: "knee jerk" does not refer to the necessary and reasonable doubt that people (including me) expressed but to those very many scientists who plainly refuse on grounds of their half-knowledge of relativity theory, i.e. on "well known facts" that are actually no more than misunderstandings that gotten popular via mediocre people doing half-cooked science outreach (popular science Einstein books for example). The public gets smarter and keeps score, and if scientists are ever more known as proud hacks that like to overstep their boundaries into areas they actually do not understand, then there goes the trust into climate science consensus, safety of vaccines, ... It is well known that those who are skeptical about global warming are more (not less) scientifically knowledgeable than average. You ever wondered how such can possibly be?
    Very well put T. and I agree wholeheartedly with that perspective.
    But I can't help wondering... In a couple of posts you have recently indicated you expect the Higgs will turn up @119GeV +/-2. and you have mentioned the 2 sigma CMS observations or "hints" in association with this belief.
    You have done a great job at shooting down various 2/3 sigma observations that have emerged from HEP collaborations over the years, so what is it that makes the Higgs observations special?
    Are you trying to tell us something via a "discreet" channel? :)

    Hi DB,

    no, I am not saying anything based on unpublished data, really. I only say that I do believe we will find the Higgs, so to me a 2-sigma effect in the only meaningful hiding place of the Higgs is something to take quite seriously. It's all a matter of prior belief, or preconception if you wish. Of course, 2-sigma remain 2-sigma, so they are, at the very best, a loose indication.

    Are you saying that if the Higgs will be found in the next couple of years at 5-sigma, then it is more likely to be found where there is currently a 2-sigma signal, than at another energy? I presume one could calculate the probability of that, but it's beyond my statistical expertise.Will it will turn out that there is almost no extra likelihood of it being at this 2-sigma energy than anywhere else, and this is a good example of human inituition failing where it comes to probability, or that it's actually very likely to be in this position? (simple analogy: if I keep flipping a coin, given I've already flipped three heads in a row, what is the chance that this will be the first time I go on to flip 8 heads in a row?)

    Hi Brett,

    the point is that indirect electroweak information points to the Higgs being light, with most of the probability density concentrated in the M<130 GeV region...

    I'm ussually all for any scientific experiment, but come on! This hypothethetical "God" particle, and I understand how cool it is to slam particles togetjher and see what happens, but give us something practicle, something tangible, we can use to improve life. Can anyone give exact figures as to how many hours and how much capital has been spent on this theory? I hate to be so critical, but I believe I could find many more important scientific projects that are HIGHLY unfunded [i.e. alternative electrical production]. The Higgs isn't hiding, the tiny little "common sense" porticle is!

    the general scepticism by physicists to the 6-sigma result on superluminal motion found by Opera as an indication of them wanting to "protect the establishment"
    I just read to here and already am amazed that an intelligent guy like you has so little reading comprehension - but such I anticipated in the text already, didn't I. I am myself skeptical about the results and have publicly said so early on and repeatedly many times! Maybe you should read again?

    And telling me (I started out in high energy particle physics) what a sigma is in particle physics is almost an insult. You really think I do not know all that??? It is beside the point!

    And I never would be so naive as to think that scientists "want to protect the establishment". Humans are generally not close to as rational as would be needed for any such conspiracy. Human brains are rationalization engines; that is what they are evolved for.
    This reaction reminds me of a plea I once made to a close one : "if a single word or bit of my expression is found offensive, please try to view it instead as an algebraic variable of unknown value to then fix the value from context as best fits an assumption of shared understanding".

    Sascha, your text is there for anybody to judge. You do spend a large part of the post saying what the post is not about; but you also write:

    The recent 2011 OPERA results, although often portrayed as just a one-off strange fluke, is actually a confirmation of the earlier MINOS experiment

    Which calls in a 1.8 sigma result as a significant one. Then you say:

    And what a confirmation it is: A whopping confidence level of six standard deviations. [...] Translated in terms of vaccine studies: Your doubting this study would make scientists call you publicly a baby killer.

    This is certainly not the first time that a new result goes against the standard interpretation of accepted scientific knowledge about space and time
    and little after:

    The only aspect important here is the bare fact of that scientists outright reject an experimental, high confidence level confirmation of a previous result, all completed by many established scientists using the most advanced, checked and double-checked means available that usual money can’t even buy.

    Ever been in the presence of scientists and tried to point out similarities between science and religion? Here we have an experiment that very many established scientists worked on with super reliable instruments, getting significant confirmation of another, already significant experimental observation, [...] yet the majority of scientists simply refuse the result because it does not fit their belief system.

    Now please try to explain in what respect did I mis-summarized your post when I wrote "the general scepticism by physicists to the 6-sigma result on superluminal motion found by Opera as an indication of them wanting to "protect the establishment" " (the quote you quoted above to explain I misread you.

    Ah, and BTW in the last paragraph above you again call a 1.8 sigma effect (Minos) as "already significant experimental observation", which I honestly find laughable from somebody who needs not be explained what a sigma is.

    "yet the majority of scientists simply refuse the result because it does not fit their belief system.

    Now please try to explain in what respect did I mis-summarized your post when I wrote "the general scepticism by physicists to the 6-sigma result on superluminal motion found by Opera as an indication of them wanting to "protect the establishment"
    Scientists go according to their belief systems, as I do often myself, and as they partially should do, which I also said in the post and repeated in the comments. Where do I conclude that this is to "protect the establishment"??? Nonsense - nothing but your reading what you want to read instead of what I write.

    you again call a 1.8 sigma effect (Minos) as "already significant experimental observation"
    "significant to 1.8 sigma" means "significant to 1.8 sigma". Do you want to give the public a long list showing for which type of science this is 'actually truly significant' in some sort of metaphysical interpretation of truth that I thought the whole point about sigmas is that we can do without? If HEP error estimation is perhaps all wrong then you guys should maybe start first learning physics properly, because error/accuracy estimation is the most important subject you guys should have learned as undergrads. If I combine a measurement from nanotechnology with one from HEP in order to find out whether a novel experiment may be testable today, could you tell me the new way of how to propagate the statistical error depending on that the two involved relative errors are fundamentally different since one is nano but the other HEP? I only know the usual stat-laws, so enlighten us.
    We have a few experiments that clearly show that, dependent on the neutrino energy and perhaps distance (as I pointed out) plus density of passed matter (as Tamburini points out) show that neutrinos arrive earlier than expected. What the hell do "experts" scream around about that this must be a systematic error because they learned their relativity theory from popular science magazines? And they do not admit that it is their belief more than their knowledge!
    Did you look at the graph you copied into your own Tamburini post? Do you see a single neutrino result that is widely off, thus indicating that neutrino experiments are all "extremely difficult" and blah blah blah? Extreme difficulty (as people now point out in order to justify special "HEP-sigmas") my ass. However difficult, the reliability (including all difficulty) is exactly what is taken care off by presenting a measurement result attached with an error. If I am unsure about stuff, I increase the error accordingly in my papers! So what are you saying? None of this weaseling around by you guys makes sense. Do proper physics, stop making it a social dance for the invited in-crowd, and the trust of the public may eventually return. You cannot on one hand tell people that Global warming is shown with statistical significance (= rigorous) and on the other hand dismiss the whole concept of significance as not being rigorous but depending on what the in-crowd feels like and stretchable all the way from 1.8 out to 6.
    Bayesian updating? I am on your side! 100% totally on your side. But your prior is what? The consensus of those people that have been selected by POP science, that are allowed to participate. Take Exxon's experts global warming prior and add HEP significance and global warming becomes an unlikely hypothesis.
    Did you look at the graph you copied into your own Tamburini post? Do you see a single neutrino result that is widely off, thus indicating that neutrino experiments are all "extremely difficult" and blah blah blah? Extreme difficulty (as people now point out in order to justify special "HEP-sigmas") my ass.
    Sascha, it is others, not HEP physicists, who take with too much excitement 1.8 sigma results. I claim that a sound measurement in a hard science discipline is not significant if it results in a number different from the expectation by 1.8 sigma, which happens 5% of the time if there is no effect. a 1-in-20 chance is not an effect, period.
    As to Tamburini's graph, that is a wild speculation, so observing that you can fit a line through four points choosing a suitable variable on the x-axis is not providing a lot of insight in the way those error bars are calculated.


    Who is excited about a 1.8 sigma result? We are talking about a six sigma confirmation with there being no measurements that disagree - on the contrary, if you look at Tamburini's graph, there are five (!) points and the error estimates overlap with the line. Also my erruditions before Tamburini's were about all experiments agreeing without us proposing artificial models that have four fine tuned parameters fitting an elephant! I do not mean to say that thus Tamburini or my proposal are correct, what I mean to say is that if something is as it is portrayed by you and many others now (just some error, only some 1.8 sigma fluke like they always happen with our awesomely difficult HEP stuff) then you would rather expect maybe the five points to be all over the place, some FTL, some STL. If they always arrive early even in quite different experiments, then it is some sort of effect, not a systematic error. Now you claim that HEP error estimation is so badly done that maybe it is an "error" nevertheless. Fine, and if this were for example energy non-conservation inside an experiment where such is absolutely unexpected, then surely we agree. However, and this is one of the main points I am making, rejecting such on grounds of merely not understanding relativity properly (killing grandma knee jerk, relativity is based on light velocity being the absolute limit) leaves one interpretation that we as scientists have to avoid like the pest if we are to talk to the public about global warming, vaccines, etc: That we are cheerleading some consensus that is not founded on proper science but on our ignorance and stupidity mixed with conformity and silencing dissent systematically via the rules of our discourse (flawed peer review, career gaming, ...). I argue this in detail here.
    Hi Sascha,

    okay. However, please note that three of the five measurements have systematics which are 100% correlated -they are not even equivalent to two independent measurements. Given the largish error bars, a line fit would be certain to pass through at least four of the "five" measurements.

    I also draw your attention to another point, neglected in all discussions but very important for the Opera scientists themselves. Their result is still unpublished -it is only a preprint for now. This may not mean much to many, but it does for the scientists who operate the experiment and who have different standards for publishing or just putting out a preprint. The preprint has appeared, but the paper might actually never make a scientific publication. Which just means that the opera scientists do not believe their result strongly enough, or that they found an error (in which case they would however let us know about it). As it is now, it is not something to be concerned too much. Sort of a "work in progress" result. This is how at least a few members of Opera themselves perceive it.

    Yes - that is why I only talk about one confirmation, not four.
    About that it is not submitted to peer review: It isn't submitted because of the (CERN internal and to be expected) rejection on grounds of misconceptions about the speed of light. Sure, since you count success in the publishing process above the actual measurements (which would have been published immediately absent mentioned headcramps) you will always be right. Whatever happens, you can always say look, what is published is the truth, thus the truth is exactly what is published and the system therefore works. How much has been lost along the way, the price paid, you do not need to care about.
    "It isn't submitted because of the (CERN internal and to be expected) rejection on grounds of misconceptions about the speed of light"

    Sorry, THIS is the misconception and the bias. You seem to ignore how a large collaboration works. The paper will be submitted to peer reviewed journal after the collaboration feels ready to do it. CERN has no word in this, nor does the general disbelief of many outside Opera.

    If it has not been submitted yet the reason is that the Opera scientists, knowing how easy it is that they went wrong in one of the many ancillary measurements that are required to compute the time difference, require more checks, to prevent putting their name black on white on a "wrong" measurement. Among the checks are those I mentioned above, plus others.

    It most definitely has nothing to do with the "rejection on grounds of misconceptions".

    I did not say that CERN/OPERA (like some boss) is rejecting anything - why do you always interpret everything I write as if I wear a tin hat? By "internal rejection" I mean mainly the brains of those who discuss about whether to submit or not and their biases and also fears. You are probably correct though that there is in this case little fear of "to be expected rejection" because these collaborations are so established, they do not have to fear such. That part was more generally speaking (like say if I write a paper and get a million sigmas, I may still not publish if I do not carefully hide any major implications that could tickle somebody slightly the wrong way).
    Tommaso Dorigo
    Many physicists feel like you that Opera result may be wrong. But, they can't prove that Opera result is wrong.
    Even if some theorists point that that result is wrong, their claims are just theories.

    Only the experiment can prove or disprove it.
    But, the experiment like Opera is very difficult. It takes long time to prove it. CERN wants lt.
    They know it is not easy to prove or disprove it.

    CERN demands like this. "Is it wrong? Prove it! Can you disprove our result? Show us!"

    Dear Younghuan,

    I do not claim the Opera result is wrong. But I do claim that some systematics were not properly computed. Indeed, I hear that you are indeed working on them.

    One example is the uncertainty in the signal shape, totally neglected in the rather simple fit you performed to extract your result.

    Another example is the 8.5 km fiber transit time, which is estimated as 40000 ns with a 1 ns uncertainty, based on three measurements done in 2007. I claim that one cannot assume the stability of the refraction index to better than a part on 40000 over a period of 2-3 years (where the average of the data time collection is), until one has re-checked the measurement after the data collection. I hear that the fiber is being remeasured. Pending this, I claim that the Opera result has possibly underestimated systematics which invalidate the claim of FTL neutrinos.

    Really, shouldn't the speeding neutrinos be interpreted as a very astute paving of the road to private funding of particle colliders? Everybody knows that public funding of future colliders may well become problematic, depending on ultimate LHC results. Financial trading has the money and loves "quants". To attract the attention of high frequency trading gurus to the neutrino promise of propagating signals in a straight line through the Earth while saving up to ~25ms antipode-to-antipode over electromagnetic signals, I can't imagine anything better than this speeding neutrinos media circus.

    I don't really understand why most of people try to relate the success of LHC in finding something to the future funding in science. And moreover for the Higgs boson (I don't believe it exist at all)..

    Accelerator science is something that today allow an increasing number of medical facilities to treat cancer, to do imaging, and related things without "invading" the body of a patient, just as a very simple example.
    Science, and in particular particle physics, is not about the understanding of the mass of elementary particles, that is just a small piece of a larger puzzle. I am not here to tell you how many things science is investigating at the moment, if you follow a scientific blog you should be clever enough to find these information by yourself, and to be aware that that particle physics is a huge field. But just talking about numbers, U.S. spend about 7 hundreds thousands billions dollar for military/army per year, now LHC is 7 billions dollar experiment (it is the most expensive) for 5+ years. Do you really think that money are a problem? We should rather worry on how our money are used, just compare the two numbers above...
    Super..neutrinos, I am not an expert in the field, but time will say.


    I don't really understand why most of people try to relate the success of LHC in finding something to the future funding in science.
    You have to look back at the PR campaign and the funding justification for this.  No one, and I mean no one, at the time said 'we can do great things with smaller experiments', it was all 'We will find the God particle.'   Now that it is built, physicists are allowed to speak up and say 'what we don't find will be important too' but back then it was not possible.  No one gets funding based on a negative or a vague justification.
    True, but there is a danger with big science projects that unfulfilled hype leads to funding fatigue. We have already seen this in the US, with the abandonment of the SSC, the disinterest in ITER and the steady rundown of planetary science exploration programmes. (Not that I would ever characterise NASA's planetary science as unfulfilled hype - it achieves magnificent advances on reasonable budgets and virtually always overdelivers, but it becomes a victim of this fatigue). For now Europe has the appetite to show that it can do what the US used to do. But this won't last if the initial promise remains unfulfilled . The bigger the project, the more important this delivery becomes. And when looked at in the context of the fantastic advances in neutrino physics or observational cosmology over the last decade, on very modest budgets comparatively speaking, the problem becomes more acute still.
    It's ok for string theorists and the like to engage in unmitigated hype, because funding theory is very cheap and makes for cheap and entertaining TV. But experimentalists need to avoid getting sucked into that game.

    Sure, though I would contend there is a lot more hype in astronomy than there is in physics.   The James Webb Space Telescope was sold to taxpayers without knowing what it would cost or how long it would take and so it is years behind schedule and no end to cost in sight.  Constellation was canceled because of budget overruns to go back to the Moon - something we already knew how to do.  The space shuttle was a legendary waste of money that did nothing for science or humanity anywhere near worth $400 million per trip.

    Yes, the SSC was over-hyped and canceled and that has caused the US to be gun shy but I don't think it is bad for American science to get to travel to Europe and Japan to do projects.

    Europeans will be gun shy too - when they find out that whatever the LHC does find is going to require an even more expensive ILC to understand.  Let's hope China underwrites that one.
    The difference between astronomy and HEP is of course that once technical success is obtained with a spatial telescope, a wealth of new results is guaranteed. In the case of the LHC, there is a sort of Ockham's selection of most sterile possible experimental result(s) that could be listed beforehand. If experimental fact ends up meeting such expectable(s) speaking of "newly opened perspectives" will be quite a misstatement of the science return on investment. And while I believe taxpayers are accustomed enough to worse lies by the politicians they elect, I also feel that would be toxic to its intellect for physics (and therefore science (and therefore mankind)) as a community to abide to it. Should I elaborate ?

    Rick Ryals
    A number of years of experience has taught me to take T's gut skepticism over a 6 sigma FTL result any day... ;)
    Regarding scientific conservatism, this quote by Craig Bohren is very good.
    I must say, however, that I am not opposed to scientific conservatism.  Indeed, it is necessary (although when faced with it myself I chafe and writhe and say bad words).  We forget that many cockeyed ideas that were resisted by the savants of the day – the Establishment is the pejorative term used – are often shown to have been – cockeyed.  Every now and then a rare genius turns out to have had a good idea despite initial resistance to it.  And subsequently, hordes of crackpots try to make capital out of this: Arrhenius was ridiculed, he was right; I am ridiculed, therefore, I, too, am right.  A manifestly faulty syllogism, but one widely appealed to nevertheless.


    1. Bohren, Craig (2001). Clouds in a Glass of Beer. New York: Dover Publications. ISBN 9780486417387.
    2. Bohren, Craig (1991). What Light through Yonder Window Breaks?. London: J. Wiley. ISBN 9780471529156.
    Robert H. Olley / Quondam Physics Department / University of Reading / England
    The superluminal OPERA result has been subject to such a campaign of suppression that they have been featured in every newspaper and tv news network in the world.


    I think you are missing the point here. Logically, there are only two possibilities: either the Opera result is correct, or it is incorrect (because of some kind of systematic errors like with the light guide as you suggested). In the former case, we would be looking at a major upset in theoretical physics, in the latter at a major embarrassment for the scientists at CERN (who really should be the most competent ones to figure out the relevancy of their results). So some kind of damage to the establishment will arise from this in any case.


    I disagree. Of the two possibilities, I see only the second as likely. And then:
    first, it is not the "CERN scientists" but the scientists members of Opera (which is NOT a CERN experiment) who are responsible of the measurement;
    second, they produced a preliminary result - which was the thing to do despite the strange result, since they had done many checks and were reasonably confident of the result. Now, before they send the paper to publication, they have the time for further measurements. If the measurement stands all the additional checks, then they will publish, and if it will one day turn out to be a unthought-of systematic error, it will not be any embarassment. Science proceeds by trial and error, and embarassing is to believe that all we produce should be the ultimate truth.

    I quote from the Opera Facebook page: ( ): The experiment is a collaboration between CERN in Geneva, Switzerland, and the Laboratori Nazionali del Gran Sasso (LNGS) in Gran Sasso, Italy.
    So sorry for not having mentioned the LNGS and all the other institutions in some way affiliated with this ( ).
    CERN however certainly seems to be central to the experiment and its evaluation: CERN is at the top of the acknowledgment list in the Opera arxiv paper, and CERN also displays Opera very much as their experiment to the media ( ).

    Such a large collaboration makes it appear even stranger that the peer-review system has been bypassed and the results published as a 'preprint'. The question is why? Were they not confident that it would be accepted by referees (or has it maybe been rejected already)? Or did they just want to take a short-cut in order to be the first to publish potentially ground-breaking results? Either way, the fact they bypassed the peer-review system in order to publish their findings is already a blow to the established system, and it would be even a bigger blow if the findings are confirmed. On the other hand, if there was some trivial systematic error in the data analysis, one would have to wonder why so may experts involved in the project were not able to pinpoint this themselves (which wouldn't really be a good recommendation for any of the institutions involved in this as far as future projects are concerned).


    Thomas, as you correctly mention, the Opera paper acknowledges CERN... That is different from saying "The CERN experiment". CERN is a lab in Switzerland, Opera is a collaboration operating at the Gran Sasso Labs.

    Anyway, you got the central point wrong. It is normal for preprints to appear before a paper is submitted, not strange. Sometimes preprints appear which do not have a corresponding publication being sent, nor any one in the pipeline. And saying that Opera thus "bypassed the peer-review system in order to publish" is completely absurd. A preprint is called that way because it is a preliminary result, and anybody has the right to produce preliminary results before they publish. God forbid we lost that right!

    The arXiv paper is actually not even a preprint. A preprint is usually understood as a manuscript that has been submitted and accepted by a peer-reviewed journal, but which has not been printed yet in the latter. In case of the Opera results, we are just dealing here with an unpublished manuscript which has not even be submitted to the peer-review process yet.

    But on a different note: you said at the end of your article:

    "The scepticism on the Opera result is not due to physicists wanting to protect the establishment. It is due to their doing their job...."

    I think you are not correctly taking the psychology of the situation into account here. Nobody would have even taken notice of the measurements (let alone raised points of scepticism) if the neutrino velocity would have been measured to be less than c. It is only the fact that the results contradict a basic theorem of theoretical physics that has motivated the scepticism here. It has as such nothing to do with physicists doing their job.


    Thomas, while what you say is of course true, I think nobody in their right mind would spend time being actively sceptical of a result which demonstrates nothing, such as a Opera measurement finding v=c . That is: if they had measured the time difference as 0+-10 nanoseconds, instead than 60+-10, I would have NOT read their paper. But then, if I had read their paper, I would probably have doubted about their systematics exactly the way I do.

    Scepticism is healthy, but you cannot apply it to measurements that, right or wrong, prove nothing. You need to focus it to experiments which, if right, change things.

    OPERA result may be incorrect not necessarily because of systematic measurement or calibration errors, but because of inherent interpretation errors.

    For instance, we may not fully understand the physics of neutrino oscillations and whether, say, unknown (sterile?) flavors contribute to neutrino propagation in matter. It may be the case that a single well-defined flavor travels less than the total distance and a segment of that distance is covered by an alternate flavor. The net result may be that a single species of neutrino travels actually less time than assumed and it appears to arrive earlier at the detector location.

    Another possibility is that SM gives only an incomplete picture of the relationship between neutrinos, Z-bosons and photons and we may somehow miss some underlying phenomena associated with neutrino propagation in matter.

    In any of these cases, what you call a "damage to the establishment" will be unlikely to happen.


    The second one is surely fine since they openly ask the community to help looking for errors and it has not been printed as fact in peer reviewed journals. The first one is a little more difficult.
    The problem is not the neutrinos - the criticism that I level is valid no matter the outcome. The problem is not that they dismiss the data but the way how so many publicly dismissed the data, namely based on an almost religious misinterpretation of relativity (which may be an emergent low energy symmetry). Having half-knowledge (v>c must time travel to kill your grandma) as the established consensus that feeds into Bayesian priors destroys the whole Bayesian method and thus the credibility of science. That is why Robert Bryce was justified in taking this issue as an example, though science cheerleader of course do not want to admit any of that.
    Clearly the bayesian prior for a significant part of the public in this case involves the long term hope for interstellar communication or ships not bound by the speed of light, and your analysis would be more convincing if it factored it in.

    And I'd say your usage of "half-knowledge" betrays numerical abuse of a kind not fitting a physicist worth the name, however well you rule numbers from the top of towers of algebra supporting your scientific imagination, given that what you imply to be the other "half-knowledge" is in fact NOT new factual knowledge AT ALL BUT recent special knowledge of highly complex speculations about facts -- something remotely comparable to epicycles. Beautiful matter, that, epicycles, one just needs to know when one is doing arts and when one is doing sciences. Or does one not ?

    Turns out I defy you to produce a bayesian estimation :)

    Let's compare two cases :

    1) The anomalous Opera measurements, taken as evidence for "special relativity as a low energy symmetry"

    2) The anomalous Nevada Ichthyosaur fossils of late fame, taken as evidence for a 200-My late artistic cephalopods ? Please note we mean not just the case of the Kraken self-portrait but also the case of a religious manifestation of smaller, social cephalopods. And similar variations, as may reveal to exist.

    I think it should make some kind of bayesian sense for you to produce a number telling how much better you find (1) as compared to (2), Or would you say (1) is so much better than (2), that both can't be compared on the same scale ? Why then ?


    Let me give you an extremely charitable reading here and plainly ignore all the total nonsense, under which circumstances you make almost sense, except you do not take into account that my criticisms (see links here and there) are about the how science is the source of public distrust in science. The prior for rejection by scientists was certainly the very opposite from what you claim to make out being the prior wished for by the public.
    The half-knowledge is not about recent physics but about what was known all along since day one: relativity is completely consistent with an Einstein ether.
    Now back to your Bayesian priors - well you agree then that there is an issue to be had about that indeed we better be careful about how we pick and defend them. If we do it as we do now, public trust into science is justifiably going to decrease.
    Well, thanks much for the treatment. Speaking of trust in science, I feel your manner of understanding the issue runs the risk of driving science into what Wikileaks wants for the governments, e.g. turning them so paranoid that they can't function. Also, generally people need to trust something, and imo the climate skepticism fashion should be understood as a sibling to "intelligent design", an emanation of the Bible Belt. Picturing it as a global product of science itself is doing it a service it doesn't deserve.

    Rick Ryals
    Or, maybe they just don't know how to apply relativity?... LOL,2817,2394747,00.asp#fbid=CovemQweT8X
    Now other scientists say that a failure to fully account for the effects of relativity is what caused the original researchers to supposedly mis-measure the time it was taking the neutrinos to travel using a GPS satellite, despite the CERN team saying they had factored relativity into their calculations.

    Times of Flight between a Source and a Detector observed from a GPS satelite
    Seems like they will get a dedicated beam for the ToF measurement:

    Well, if the greek economy got a second chance, why they wouldn't?

    Bobby Knight
    To follow up the comment from Boris Borcic (not verified), I found this interesting link.
    Hi Tommaso
    About "Measurement of the neutrino velocity with the OPERA detector in the CNGS beam"
    ( )
    Somewhat late, but I had to think first..

    In an experiment there is always a stimulus and a response.
    Using a response for which there is no corresponding stimulus is invalid, because there was no experiment.
    Using a stimulus for which there is no corresponding response is invalid as well, for the same reason.
    The latter is the case in the current analysis of the OPERA Collaboration.

    Only a part of the PEW contains start time information of the proton (stimulus) that later resulted in a neutrino detection (response).
    The remaining parts or the PEW contain start time information of protons for which there was not a neutrino detection.
    The current analysis allows the remaining parts to determine the shape of the PDF; it cannot be ruled out that this results in bias, because of the irrelevant start time information in the PEWs.

    A number of physicists pointed out that these remaining parts are required for constructing the PDF to enable the maximum likelihood analysis and they dismissed the idea that this was invalid.
    This seems the mainstream view and I am wondering what to think about that.
    It explains why the analysis is taken for granted.

    See also


    Hi Bert,

    there cannot be any bias due to the detection of a neutrino in Opera on the shape of the proton spill. That is, unless Opera used some triggering procedure (opening their "gate" only after a signal from CERN arrived telling them that a bunch was coming). Such a procedure is used by other experiments at GS (eg. Icarus), but not in Opera.

    Hi Tommaso

    So, if I fire a shot at you at t1, in order to determine what time it takes to hit you, and I miss you, you think t1 is still useful for the determination.
    Or, if you buy a lottery ticket and it wins no prize, you keep it because of it's value?
    Please, first take notice of my arguments and then answer.


    If I buy a million lottery tickets and win three prizes, I only know that the chance of winning a prize are three in a million by using the full statistics, not just the three winning tickets.
    Hi Tommaso,
    You neglected my firing example, but that's a realy good approximation of what OPERA did.
    A PEW starts as a bunch of lottery tickets, eventually most PEWs are discarded because all tickets in their bunch were worthless.
    From the remaining PEWs, only one ticket won a prize, and the rest should be discarded.
    Instead, OPERA neglected the prize ticket and tried using the others, with the spectacular result.
    OPERA's method cannot be explained, maybe it can be excused.

    Bert Morrien
    The newest outcome of Opera's neutrino velocity measurement included also the result of an alternative analysis.
    This result was compatible with the earlier finding, and so was the result of a new experiment with much shorter pulses.
    This means, Opera’s current analysis must be valid.
    This means also that Opera knew exactly what they were doing.
    Consequently, the PDF obtained by summing the PEWs is valid, despite the lack of PEW parts with a corresponding event.
    This is because with enough events, the event distribution resembles the shape of the PDF sufficiently for trusting the outcome of a maximum likelihood analysis.
    It is regrettable that this point never became clear to me before.

    The lesson learned is that declaring the PDF and Opera’s analysis invalid is a good example of narrow minded reasoning; a humble apology is in order here.

    Don't be too hard on yourself Bert, this is a complicated piece of physics and there's dozens of ways to go wrong for the experimenters; on the other hand, the same can be said for anybody willing to try and find the bug.