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CERN | Geneva | Switzerland

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Nothing travels faster than light but gossip!

This is what one of my professors told us way back then at the end of a very serious lecture on relativity. And rumors have certainly been going fast and wild at CERN this past week. The news of the possible spotting of particles travelling faster than the speed of light is just as exciting as it is unexpected. This could be the most earth-shattering discovery we’ve had in decades.  Hard to get any wilder than this! The whole question now is to determine if this is really the case.

I remember being a teenager and hearing about tachyons, these hypothetical particles that could travel faster than the speed of light. They were supposed to have a speed at rest not of zero, but equal to the speed of light. Not only that, but they would lose mass (that is energy) as their speed increased! I remember the shiver I got then. I got it again when I heard about this measurement earlier this week. So here are more details.

The OPERA experiment is located in an underground laboratory under the Gran Sasso mountain in central Italy 730 km away from CERN. Neutrinos produced at CERN travel through the Earth’s crust to reach the OPERA detector. That’s what so great and so hard with neutrinos: they can zip through matter nearly unaffected, making them also terribly difficult to detect.

OPERA was built mostly to detect the appearance of tau neutrinos from a beam of muon neutrinos, a phenomenon called “oscillation” that enables one type of neutrinos to mutate into a completely different type when travelling over a large distance. This is something that had never been observed directly before but OPERA spotted one such event last year. To do so, they need to correlate the appearance of tau neutrinos in their detector with the arrival of muon neutrinos sent from CERN. Obviously, getting the timing right was essential, hence their careful checks on the arrival time of the muon neutrinos in Gran Sasso.

And there, surprise! The neutrinos reached the Gran Sasso laboratory 60 nanoseconds (i.e. 60 billionth of a second) faster than light travelling over the same distance, even though neutrinos are expected to travel slightly below the speed of light.

Both CERN and OPERA upgraded their equipment to use the most sophisticated timing devices and the same GPS satellite to synchronize their atomic clocks to within one nanosecond. The timing equipment was calibrated by the Swiss Metrology Institute and independently verified by the German Metrology Institute PTB (Physikalisch-Technische Bundesanstalt).

The distance between the point of emission at CERN and the point of detection in Gran Sasso was determined by CERN surveyors to be 731278.0 ± 0.2 meters, that is a 20 cm uncertainty over a distance of 731 km! All experimental errors amount to ten nanoseconds, six times smaller than the effect observed, a clear evidence if (and only if…) nothing has been omitted. This is precisely what further scrutiny from the scientific community at large and other experiments will try to determine in the near future.

So after months of very thorough crosschecks, the OPERA collaboration is finally going public with it. They are looking for independent measurements to refute or confirm what they observe. Anything is possible given the complexity of the measurement: a technical flaw, a small calibration problem, an experimental bias. Nothing can be neglected.

But if it turns out to be real, much work will remain to get the proper theoretical interpretation and its implications on relativity. We will still have to figure out if these particles are travelling faster than light or if they are just sneaky little neutrinos taking a shortcut through some extra dimension…

Pauline Gagnon

To be alerted of new postings, follow me on Twitter: @GagnonPauline

  • Daniele

    Hi, i’m an italian highschool student, interested in physics.

    Last night I saw the news on the Twitter page of CERN, and they were talking about result that should have been checked before the pubblication, but they teased with the presentation of “light speed neutrinos”.

    Today they had the conference, I’m not so good at english so I understood something, but not too much.

    My question is: If Einstein told us that anything couldn’t travel at the speed of light, neutrinos, or maybe particles, would be automatically able to ignore the Space / Time limits?

    Otherwise a new definition of “speed of light” should be required? If the light doesn’t have the same speed at any time, wich are the factors that would allow that?

    I have some notion of phisycs, poor for the modern physics though, but I would appreciate any comment, or response.

    Thank you,

  • Pingback: Neutrinos and speed of light | It's Forty Two!()

  • Some time ago I’ve heard about travelling faster than light, by bending space between two points.

    Is possible to neutrinos to do that? And if not, what other physical limits we have to rethink about?

  • Prof. Byron Brainard

    I suspect that this “faster than light” travel happens in part because you have a separation between space and time as we know it. So therefore potentially a different dimension. Einstein gave us the speed of light in our four dimensions, however, did not take into account the potential for other dimensions. Keeping in mind that this has not been verified yet, just a potential thought on what might explain this phenomenon.

    Prof. Byron Brainard III

  • rayn

    Small typo, “loose” => “lose”.

  • Padraig

    One question I had was whether the test takes account of the curvature of the earth and the fact that the neutrinos would go straight from one point to the other rather than a slighty curved route in line with the curvature of the earth as this would decrease the distance between the two points. The GPS mapping probably takes this into account but was just curious.


  • Quantum Diaries

    Good catch, thanks!

  • Ricardo Villanueva

    My name is Ricardo Villanueva and I am a high school student into physics.
    My question is: Is it not possible for the neutrinos to travel through another dimensions? The neutrino is a subparticle of which information is not vast.
    Also, is time is relative how do we know for sure this 60 ns are accurate?

  • I think that IF confirmed, I agree with Byron – I’m not an expert but it’s the only explanation that my brain can comprehend (apart from Einstein being completely wrong..). The speed of light would be confirmed as the maximum speed, but only in our space/dimensions. The neutrions would take a shortcut, just like if you bended a paper and pinched a pin from one side to the other.

  • Nanning


    is it possible that the rotatoin of the earth slidly invluences the travalling neutrino’s,so the arrival is a bit earlier because the neutrino’s travel opposite the (check piont and) rotation of the earth?

  • Paul St Clair Terry

    Neutrino measurements have been notoriously unreliable in the past and so my hope and expectation is that this will prove to be an anomaly that does NOT contradict the fundamental laws of physics… One issue with the speed of light is that this is not some barrier that limits velocity but is the assymptote beyond which velocity is undefined. Given the relativistic effects of time-dilation and Fitzgerald contraction (along the path of travel) and what happens as one approaches (but never reaches) the speed of light, it can be argued that the speed of light is not a velocity at all but some limitational state which can never be reached without infinite acceleration (in which case it is reached instantaneously). Since velocity is defined in terms of space and time, superluminal velocity is a definitional absurdity given our current understanding of physics. On an aside, one of the consequences of relativity is that the notion of absolute rest disappears. However, the notion of simultaneity is not lost as evidenced by Bell’s interconnectedness theorem. Non-locality is not evidence of superluminal effects but of instantaneous and simultaneous state-change in observable reality… As I glance into my rapidly draining glass of claret, I ruefully consider the cataclysmic impact of proven superluminal velocity on my understanding of mathematics, physics and philosophy and decide to pour another glass…

  • mustafa

    As far as ı concern that we should not think about einstein formula. Maybe, cases which particles travel faster than light can be invalid. As einstein’s formulas be invalid for heavy mass and, this stuation also can be diffirent formula . 🙂

  • Adam

    I was wondering after I’ve heard about this about two things:
    1. From far away, it looks a bit like 1980s “cold fusion” story. I know it should not be the case, but I just can’t help myself wondering whether we’re wrong again, cause at the moment it looks like veryone’s convinced there is an effect. I certainly hope that’s not the case 🙂
    2. Forgive me my ignorance, but I believe I’ve seen somewhere similar speed of matter – there are many theories of Big Bang, but at least some of them (if not all) utilise inflation model, which assumes particles moving faster than light. Could it be somehow similar?

    Have a good weekend,


  • Stefan Hacko


    My name is Stefan Hacko, I am a High School student from Kikinda, Serbia (18 years old).

    Today I was discussing this topics with my physics teacher and he suggested that neutrinos are massless particles so that speed grater than the speed of light is no problem. Later I found in my physics book that it states that neutrinos mass is 0. (But on wikipedia I found that theory suggest that mass is not 0). Could this experiment proof that mass of neutrino is 0.(Is the mass of neutrino actually measured before /experimentally/?).

    My other question is what is the method used for detecting neutrinos. I have red a lot about Japanese detectors is this one (in OPERA experiment) of the same type? (How do you know that neutrinos are from CERN collider and not from the Sun /space/?).

    Also is it possible that neutrinos are bending space-time and “skipping” space?

    Hope that somebody could give me any answers especially the ones.

    Stefan Hacko
    [email protected]

  • Paul St Clair Terry

    I am not sure – too much good wine and multitasking unsuccessfully in the kitchen – but I imagine you are referring to tachyonic inflation which is not orthodox doctrine… Tachyons are essentially a mathematical construct which arise from the completeness of the field of complex numbers… Though hugely useful in mathematics, one might ask what interpretation the square-root of minus one has in the space-time continuum…

  • Paul St Clair Terry

    Stefan, I am sorry to disappoint you but your teacher’s suggestion that massless particles are capable of superluminal velocities still contradicts special relativity… Consider the photon (the observed state of light). In any event, the neutrino is not considered massless, just very small… The notion of bending space-time is interesting given that space-time is not an existential “fabric” in which matter is situated. Rather, it is space-time measurement that “deforms” relative to its proximity to matter… I hope that is sufficiently clear but I am slowly being swallowed up in a miasma of alcoholic indulgence as the wine relentlessly takes hold…

  • eSemmel

    This question was asked at today’s presentation. The answer was that it has been checked and the error from that would be too small to matter.

  • ismet

    1) Neutrino mass hasn’t been calculated yet but experimentally we know that neutrinos has a really small mass . This was found around 1998 before that neutrinos were assumed to be massless because of this older physics books will state that neutrinos are massless particles.

    2) There are some cosmic background in the experiment but compared to the real neutrinos (the ones going from CERN to Italy) it’s much more smaller. Infact if you watch the conference you can see the graph with the cosmic background. Other then that in the experiment they actually now when the beam is leaving CERN so they estimate the time when the particle would reach italy. So they only take the data who are in the estimated time region so this really clears out the cosmic background. And because the cosmic background is random you can rule out the extraordinary events because these experiments are conducted frequently.

  • Ted Nellon

    Could the superliminal effect originate from backward causality? According to this paper [1], 16,111 neutrino were detected. 16,111 is a prime number. Could a LHC team be sending a message from the future? Is it warning?


  • Prof. Byron Brainard

    @mustafa – What you are saying is true AND they could be valid as well AT THE SAME TIME! Of course this gets into uniform field theory or parallel universes at least. What I mean by this is that our central nervous system is what does the readings, there could be an explanation outside our nervous system that allows the observation to be true.

  • @GagnonPauline Pity they didn’t do an elementary check of their statistics. http://t.co/SCUK9TvG

    @Ten Nellon ROFL. How do you think I put together the refutation so quickly? 😉

    Tachyons are great fun, but I haven’t analysed them for about 20 years now. Pity the result is wrong — it would have been fun to dust off those old references.

    @Stefan Hacko If neutrinos were massless they would go at the speed of light. (Assuming relativity is correct, and it’s stood up to every test for the last century or so.) If they were tachyons then they could not be brought under the speed of light — they would always have to be faster than light. For that reason, their “mass” (i.e. what some elementary books call their “rest mass”) is not a physical quantity because they could never be brought to rest. However, even at a classical level, one can consider the quantity m^2 to be negative. (I’m not saying that tachyons wouldn’t throw the cat among the pigeons re causality, of course, just letting you know of some of the work that has been done on tachyons in simple terms.)

  • stefan hacko

    Thank you very much for all the answers.

  • Pete B

    How big a job would it be to swap sender and receiver so neutrinos flow in the opposite direction? I assume the kit’s not cheap, but much of the cost must have been in building and construction work. (If we’re questioning Einstein, might as well revisit Michelson-Morley as well?)


  • Marcel van Velzen

    Hello Stefan,

    According to standard relativity theory a massless particle must travel at the speed of light. I wil try to explain you why.

    The full form of Einstein’s E=mc^2 is

    It is not difficult to rewrite this as:

    Now if you set m=0 in this relation you see that the two E’s cancel and you get v=c.

    In a sense the rewritten formula is more general than the original formula because in the original formula you get E=0 if you put in m=0 which is not true. So the original formula already assumes that m is not equal to zero but by rewriting it, it is possible to look at the asymptotic behaviour. The more general formula for energy is E=hf with f the frequency of light or the frequency of a massive particle in such a way that the original formula is true.

    So the big difference between a massive particle and a massless particle is that for a massive particle we can run alongside it and then it seems at rest but with a massless particle this is not possible, it will always move at the speed of light. This is not a continuous thing, it is possible or it is not possible and this indeed is one of the great mysteries of physics.

    Good luck!

  • Paul St Clair Terry

    If indeed the OPERA team has made such a basic miscalculation, this will be hugely embarrassing and will underline the importance of mathematical oversight where experimental data are concerned… In this particular case, the statistical basis is not especially demanding which will only add to the eventual egg on face, assuming that you are correct. Once again, I conclude that it is much safer to be a theoretician where experimental results are un ugliness with which one can do without…

  • Marcel van Velzen

    Hello John,

    That is far more precisely what I wrote in the blog “elementary my dear neutrino”:

    On the neutrino speed: the faster than light neutrino speed is equivalent to saying that we cannot move the proton PDF of figure 11 of the original article by 0.2 mm, which in nonsense.

    So I fully agree!

    The problem is that the people at CERN are frustrated by not finding new physics and are losing their minds. The fact is: not finding new physics is nice (because it means the standard model gives a very good description of nature at this energy level) and finding new physics is also nice. BUT if you really think hard not finding new physics (laws) is better!

    Good work!

  • Ben Snelder

    Hello all,

    I am just an averige ‘Stephen Hawkings’reader, who was very good at physics in highschool.

    Ages ago I read an article stating that ‘detected neutrinos from a supernova arrived here e few seconds earlier than the light of the supernova’. I always thought that the reason for this was: neutrinos travel in a straight line, where light is bent by the masses it passes on its way – therefore they travel at the same speed, only light takes longer detours.

    Can’t it be that the maximum possible speed is a bit higher than the speed of light? The reason, light always is influenced by the gravity.
    Neutrinos are not influenced and are therefore able to travel at this maximum speed.
    Were light to travel in a space – without gravity – it would be travelling at this maximum speed as well. Time would also be at its fastest possible, being influenced by gravity as well.

    One could say as well, in our universe time is always slowed down by gravity. Near a black hole our known second could take a years time at earth. The light near this black hole would take an earths year to travel near 300.000km, or not? And still be the speed of light, because it takes only a black holes second.

  • carlos

    Is the SN 1987 the biggest clue to guess the “standard” neutrino’s speed? Because in that case maybe the same kind of neutrs came to us years before the light (i mean, years before we knew there was a SN, so we didn`t notice). I wonder if this would be a mess if just one only experiment shows an strange speed, and if it would be a beatiful mistery when both experiences, OPERA and SN1987 showed us the same rare results, with the same kind of circumstances on the neutrs.

    If SN1987 had sent us this “tachyoneutrinos”, when had they arrived earth?

    Just playing with possibilities.

  • Bill J Grossman MD

    I’m not a particle physicist just a general scientist and quantum physics buff. The CERN website has an amazing database of articles in quantum physics and when I searched “ tachyonic neutrinos” Low and behold out popped some articles from:
    Rembielinski, J from Poland in 1995 and 1996, as well as Park, M I in 1997 in Korea which predicted that electronic and muonic neutrinos probably travel faster than light according to their measurement of “negative mass squared”
    Given the fact that this was predicted and measured in the 1990’s and in light of the recent evidence. This theory is getting some legs. I do have a few questions however. How do you detect neutrinos when they can fly through mountains at the speed of light without interacting with anything. What’s the collector made from, that interacts with neutrinos which supposedly are the most weakly interactive particles discovered so far?
    Also I would like to point out that GPS uses Einstein’s General theory of Relativity and Lorenz equations which state that time is relative to the gravitational pull of the earth. So even if the existence of tachyons means that Einstein’s Special theory of Relativity needs to be revised, it doesn’t mean that the GPS data used to make the calculations are flawed because GPS data is not dependent on any speed limit.
    Dr. Bill Grossman
    [email protected]

  • Franco Martinez

    Since I can find here people who can actually give me a good answer to this, I’ll ask (I’m just a guy who tries to know physics): What would be the implications if we get the outermost parentheses in [sqrt(1-(v²:c²))] have a “module” or absolute value, instead of nothing? I mean, I’ve seen long time ago the deveolpment which took to that equation, but since I’m not an experimented matematician I miss to see how could we introduce an absolute value in that equation, allowing tachyons (or whatever other particle) to exist within this “revised” relativity.

    I’m sorry for my suggestion if it offends you for being so illiterate, but it is in fact my ignorance, and my “boldness” by reading regularly this post. Greetings.



  • One way to interpret the new data is to assume a new absolute speed limit slightly higher than c. But I think it may be much more useful to think of superluminal neutrinos as (1) particles traaveling backwards in time (the mathematical equivalent of moving faster than c), or possibly (2) particles with negative masses. Either way, the standard model of cosmology would be rocked.

  • Victor Gudym

    In our opinion, the new experiments, where the neutrino velocity was measured, are not unexpected. The failure of the relativity theory in that concerning the light velocity is already revealed in the experiments on the electron-proton scattering (R Hofstadter, Rev. Mod. Phys. 28, 214 (1956)).
    Hofstadter studied the scattering of electrons with energies of 188 and 400 MeV. It is quite obvious that the velocity of electrons with such energies exceeds significantly the light velocity. But then nobody noticed that the distribution of scattered electrons corresponds strictly to the famous classical Rutherford formula.
    Hofstadter modified the Rutherford formula with the help of formulas of the relativity theory and made conclusion that only the relativity theory allowed one to explain the experiment.
    But we have recently shown (V.K. Gudym and E.V. Andreeva, Journal of Surface Investigation 1, 223 (2007), V.K. Gudym and E.V. Andreeva, Concepts of Physics IV, 553 (2007), V.K. Gudym and E.V. Andreeva, Concepts of Physics V, 435 (2008)) that another explanation is possible on the classical level without the use of the relativity theory. Respectively, no limiting velocity of particles exists.
    We believe that there is no sense to restrict themselves only by the experiments with neutrino. It is necessary to return to the study of the scattering of relativistic electrons, where the erroneousness of the relativity theory can be also demonstrated in a more clear way.

    V.K. Gudym

  • Math Bollen

    Does anybody know if a correction has been made for the small delay in speed of the GPS signals through the ionosphere? The thickniess of the ionosphere (and thus this delay) is dependent on the latitute, it would thus give a systematic error.

    Just a though that chas came up at night ,,, but probably something that has been corrected for.

    Math Bollen
    Luleå University of Technology

  • Marcel van Velzen

    Hello Ben,

    We should not speak about mass if we discuss curvature of space-time. It is energy (and momentum) that curves space. And anything with energy (and momentum) feels gravity or in other words moves inside the curved space. Also if there are no other forces you don’t feel gravity, just like astronauts don’t feel gravity when they orbit the earth. So inside a curved space all things move in straight lines within this curved space (shortest distance between two points). So neutrino’s and photons follow the same path in a gravitational field and contribute to the curvature of the space-time around them depending only on their energy (and momentum).
    To say neutrino’s don’t follow space-time is to say they don’t have energy and momentum which is funny because the existence of the neutrino was postulated to save the laws of energy and momentum.

    I hope this helps!

  • Stefan Hacko

    @MarcelvanVelzen, @JohnCostella, @PaulStClairTerry thank you for the answers, I really appreciate them.

  • I have been telling people for years that light cannot travel faster than the speed of light, but having said that the components of light particles cause light to travel as a wave because they do and are traveling faster than the speed of light within each photon. The direction of light appears to be in a straight line only because of the multiple course corrections caused by the components of the photons. Similar to guiding a boat through water. The more course corrections the shorter the wave length.
    Sincerely, Joshua Stevens 303-809-7885

  • Hi Ben,
    If a neutrino traveled one inch it would also have traveled a shorter distance then a photon that traveled that same inch because the photon traveled up and down and sideways in a spiral making many course corrections to continue in the straight line and exist as a wave.
    If you added up the total distance of the photon’s travel it would stretch out to slightly more than an inch. It may be that the neutrino does the same thing but to a lesser extent than to assume that the course of the neutrino was 100% straight.
    I would also say that mechanical time as recorded
    by anything made out of matter could slow down near a black hole but a second might still be a second and to leave open that possibility.
    What if the clock was made from neutrinos?
    Sincerely, Joshua Stevens
    [email protected]

  • No, I am absolutely convinced you are on the wrong path here. If they had accumulated data for a few more days, the number of neutrinos would have been different, but their result would be the same.

    I am afraid you are taking science fiction for reality. Mind you, if this effect is real (but this still remains to be proven) then reality will start sharing resemblance with science fiction!

    Let’s try to deal with facts here, that’s what science is about.

  • Hello Daniele,

    all particles should obey the same laws, neutrinos included. There is no reason why they could ignore space and time as we know it. This is why this result is so puzzling. But the first thing to do, is try to crosscheck everything that could have gone wrong. Now with the whole physics community following this, the researchers involved will have tons of suggestions of possible things to check.

    And a new definition of the speed of light is difficult to conceive. It describes a very precise thing. So I doubt this will be the answer.

    Also, the MINOS experiment at Fermilab in the USA should be able to redo this measurement one more time in the coming months. They did it before but it was not precise enough. Now they will improve their technique and try again. If they also get the same result, we will have to think of an explanation and consequences of this measurement.

  • Hello,

    of course, if somehow the neutrinos travelled on a shorter distance, they would arrive faster. If they have access to new dimensions somehow, and that allows them to take a shortcut, all becomes explained.

    But it is too early to speculate on what might be happening. First, we need to make sure this is true. There are so many places where this measurement could have gone wrong given its complexity, despite the incredibly thorough checks the authors made.

    Once we have an independent check from another experiment, and more tests from this group, then it will open the speculation season in earnest. But as scientists, we first need to establish this result beyond any doubt.

  • Hello Ricardo,

    for this travel through other dimensions, see my answer above to Quisco Mena.

    Regarding the fact that “time is relative”, this means that for the neutrino or anything else traveling near the speed of light, time will start dilating. This means it will seem much longer to them. “Time is relative” means it flows at different speed depending on the speed of the person or object traveling.

    In this case, the experimenters were measuring the time in 2 places that were not moving with respect to each other. So the time was the same at CERN (point of departure of the neutrinos) and Gran Sasso (the lab in Italy where they were detected. So the 60 nanoseconds time difference is ok, providing there was no error in the equipment or method used.

    I hope it clarifies this. Pauline.

  • Thanks for putting in the big IF. Of course, a shortcut is easier to understand but if and once this is confirmed beyond any doubt, then we will have to figure out what’s happening there.

  • Hello Pete,

    this would imply moving the SPS, which is part of the 27 km-long LHC (the accelerator from CERN near Geneva that produces the neutrinos) to Italy, 730 km further… Is your suggestion a way to see if the direction of the earth rotation has an effect? If so, this has been calculated and was found to have no effect.


  • Bill J Grossman MD

    David, Since these tachyonic neutrinos were assumed to initiated at CERN and later showed up at OPERA, that would imply they are travelling forward in time. I’m not denying that you can postulate the existence of reverse time travelling neutrinos by manipulatimg Ensteins equations. The causality of experimental results just don’t suggest that these particular presumably tachyonic neutrinos are travelling backward in time.

  • Bill J Grossman MD

    Josh, I find that you make an interesting point. You did have a typo above however. The more course corrections the longer the wavelength would be. Although the energy of light is dependent on it’s wavelength, the speed of light is a constant and has not been shown to be dependent on the wave length.

  • PGroot

    I did wonder whether they calculated the distance through the earth rather than around its curvature, but that would have had a difference of about 37 microseconds rather than 60 nanoseconds.

    Perhaps it merely means that the previously accepted value for the speed of light is too low by a factor of 1.000025. But it was supposed to be good to 9 places. (Since the meter is now defined by the speed of light, it means that the meter and the size of the earth would be in error.)

    One small possibility of error is that the earth is not a perfect sphere, or even a perfect ellipsoid. If the calculations of distance did not take that into account, it would cause a small error.

  • Pauline Gagnon


    yes, this is taken into account. Remember that only the neutrino speed (or rather the time they took to travel the distance) was measured. No real light took the same journey. It was not a race between the neutrinos and photons associated with light. To estimate the time light would have taken to travel the ***same*** distance, namely the direct path through the Earth’s crust, they measured this distance and divided by the speed of light.

    For the neutrinos, they measured the time elapsed between their departure from CERN and arrival at Gran Sasso. Then they compared the two. The neutrinos appeared to have arrived 60 nanosecond faster.

    The effect of the gravitational pull on the neutrinos, given they have a small mass, was also taken into account but was found to have no impact.

  • Pauline Gagnon

    Hello Joshua and Bill,

    be careful: do not confuse things here. The light travels at the speed of light and goes in a “straight” line, which is curved in our world due to gravity. There is the wave-particle duality but you cannot mix them up. The photon does not move up and down to follow the amplitude of the electromagnetic wave. The photon moves on a straight line, there are no course corrections like you mention. The electromagnetic perturbation also travels at the speed of light. The ups and downs of the electromagnetic field have nothing to do with what you called “course corrections”. There are no such things.

  • Pauline Gagnon

    Indeed, they do use the direct path which is through the earth’s crust, exactly where the neutrinos traveled.

  • Jacek

    ok, but if they took shortcut, why it would be so small?

  • Marcel van Velzen


    Hello Pauline,

    I recently heard that John Costella has withdrawn his claim that the statistical analysis of the Fig 12 data is wrong. I am certainly sure that the statistical analysis is correct, given al kinds of statistical assumptions. However, I think it is not necessary to assume anything to see that we can easily move the graph of Fig. 12 of the original article by equal or more than 60 ns. I think it’s a common mistake by people not trained in signal processing to think that using the eye to judge more or less a curve through a number of points is incorrect. It is not. It is what humans are very very very capable of. We can surely make a theory of a curve or make a theory to automate this process but the human eye and billions of brain cells working as a sophisticated neural network is at least as good in this. We can also take account of the combined error bars when we use the brain. For example, recently Fermilab made a claim of a bump in some data. I looked at the data an saw immediately that with a little fantasy including the error bars it was possible to (almost) remove the bump. And indeed a later experiment saw nothing. I claim that this is the case here also and the last time with the Fermilab data it turned out to be right. If the shift is inferior to 60 ns then the data should incorporate this and it would not be possible to shift the data that much by eye! Don’t get impressed by Gaussians or Breit-Wigner curves, that is theory, experimental physics is about observation! And that said by a theoretical physicist should mean something.

    Good luck!

  • Josef Riedlberger

    “Both CERN and OPERA upgraded their equipment to use the most sophisticated timing devices and the same GPS satellite to synchronize their atomic clocks to within one nanosecond.”
    How can you do that? Correct me please. If you would have a vacuum tube from Switzerland to Italy and send some photons through it, then same time means when the photon arrives. But there is no vacuum. Are the light-speed-in-matter corrections so small? A phase shift of 60ns due to mobile phone interference?
    I was just puzzled by the words “synchronized within one nanosecond”.

  • Pauline Gagnon

    Hello Math,

    I believe this is indeed taken into account. Aidan RandleConde who was blogging live for the Quantum Diaries during the presentation of these results at CERN on Friday) note this question that was asked after the seminar:

    (see http://www.quantumdiaries.org/2011/09/23/live-blog-neutrinos/)

    Do temperature variations affect GPS signals? Answer: Local temperature does not affect GPS measurements. Two frequencies are used to get the position in ionosphere. 1ps precision possible, but not needed for OPERA (note: 1 ps is one picosecond, 1000 times smaller than a nanosecond). The time measured was 60 nanosecond so this effect would be really small.

  • Pauline Gagnon

    Hello Adam,

    indeed, this could go out the same way the cold fusion results went… Having attended the seminar at CERN last Friday, it was clear the experimental team had done many thorough checks. But errors are always possible which is why we always like to have an independent check. The Minos experiment at Fermilab should be in a position to do it.

    As for your second point, here is what my colleague, a theorist has to say about it. There in no problem with having space expand faster than the speed of light. This is indeed the basis for inflation or de Sitter cosmology, this does not imply that signals can propagate faster than light. This is what Einstein says. Another example: phase velocities can be faster than light, but not group velocities.

    See here more details on the basics of phase and group velocities

  • Pauline Gagnon

    Hello Bill,

    since I was not familiar with this work, here is what my colleague, a theorist who knew more about this, has to say about it; apparently, they never made exact predictions but only played with the possibility of negative mass squared:

    There are a number of problems in the formulation of Rem… et al, in fact there are
    some interesting papers of Chodos and Kostelesky where they try to put bound on
    breakings of Lorentz invariance that would allow for faster than light propagation.
    There are simpler ways of doing what Rem.. et al do. Tachyonic representations
    of Poincare are known since the time of Wigner’s theorem, and many people have
    tried to make sense of theories with tachyons with mixed results. With fermions
    things are a bit more subtle mathematically, but you can also manage to have
    fermionic tachyons. I am sure all these things will be revised with simpler methods
    in the next few weeks. But neiter Rem.. nor the koreans “predicted” anything about
    the electron or neutrino masses, they simply played with that possibility, which is
    a completely different thing.

  • Pauline Gagnon

    Hello Franco,

    There is nothing wrong in Minkowski space with space-like trajectories (where this term would be negative), there is no need to take any absolute value of any of the like.

    It is beyond the scope of this blog to go into all fine details of the theory of relativity. Instead, I would like to bring a word of caution here: the results presented last Friday by the Opera group still needs to be corroborated by another group or other measurements. Until we are certain this effect is real, it is premature to speculate on the implications. Tempting, true, but still very premature…

  • Pauline Gagnon

    Hello Carlos,

    if the neutrinos had traveled faster than light by the same amount as what was measured by Opera, then they would have arrived months before the light emitted by the supernova. In fact, the light came 3 hours **after** the neutrinos but this is just because it took much more time for the light to escape the dense medium created by the supernova explosion. Neutrinos were able to escape right away, whereas light only came out once it calmed down a bit.

    A theorist from Rutgers, Matt Strassler, has put together a very nice piece of information on this supernova, SN1987A. You will find many more interesting results there:


  • Gaines

    Just a side note to complement all those above who have exchanged ideas, postulated implications and explanations, etc., all without insulting or belittling the ideas of others. It’s refreshing to see in an Internet article comment section.

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  • Sajid

    Please make fast and public it..we are very much exited

  • My question had to do with media coverage of the announcement and is fairly basic on the physics – is it true that Einstein’s special relativity theory says nothing can travel faster than the speed of light? doing some searching, some lay sources in books suggest that einstein did not make such a blanket statement, and that some atomic particles may be able to travel faster than the speed of light (or at least this was not explicitly rejected).

    Unlike cold fusion, this paper seems to bend over backwards to not make unsupportable claims or conclusions. But the media take is still going to be “IS EINSTEIN WRONG?” and if the results are disproven, “EINSTEIN VINDICATED.” haha.

  • B.Bangaru

    Could it be detecting a signature wave before the actual particle arrives?

    Is it possible that like in the case of a Boat traveling at certain speed creates a wave in front of it and the detector is picking up certain signature before the actual mass particle arrives only slightly delayed (and below speed of light) below the resolution of the detector?

    I am not a Physicist or a Scientist. but simply thinking that at such high resolutions and speeds, could a simple Boat bow wave phenomenon offer some explanation?

  • Marcel van Velzen

    Hello Milo,

    I think that now that the Einstein Podolsky Rosen (EPR) paradox has been verified experimentally, the best statement is that information can not travel faster than light. In the EPR paradox there is an instantaneous effect from one particle on the other but it can not be used to transmit any information because the outcome can not be influenced. This is a beautiful example of how quantum mechanics and relativity go hand in hand.

    For some atomic particles that can travel faster than light I suppose you refer to virtual particles. If you on your bicycle with only an initial speed try to cross some hill and the hill is to high you will not make it. Classically You can try a thousand times you will never make it. In quantum mechanics however once in many times suddenly you will find yourself at the other side of the hill. This is called tunnelling. Of course the fact that you have crossed the hill means that while crossing it, the normal classical laws of energy and momentum are not valid otherwise you would not have been able to cross it. So there you could say that you can go faster than light but it is really not clear at all what happens during tunnelling.
    I hope I didn’t confuse you even more!

  • BestTheory

    The cause is obvious. The universe suffers from rounding errors allowing some particles to slightly exceed the speed of light.

  • anna v

    If one looks into how the GPS system works, one will see a lot of corrections, including refraction in the atmosphere and ionosphere. A simple summary: http://web.ics.purdue.edu/~ecalais/teaching/geodesy/GPS_signal_propagation.pdf . A more sophisticated measurement is used in the experiment of course.

    The danger when one reaches such precisions is that one may be very precise but not accurate: a very precise clock can be systematically off. It might be possible that the GPS has redefined the meter ( which is a fraction of the velocity of light in vacuum) since it is working in a non vacuum environment and corrects for it. This would not affect navigation and geodesy, but will show up in such a measurement.

  • Dear Sirs.

    Supposing the neutrinos go in fact faster than the light speed, could it be due to the fact neutrinos do not interact with matter as light do? Could it be possible to compare the speed of both without the matter’s effect on fotons, to compare both speeds in identical circustances?

    José Carlos

  • Niels

    Isn’t the “speed limit” of c just a property of the electromagnetic force and thus only applies to elementary particles who can interact with the EM force; like quarks, electrons, (thus virtually all matter in the universe), but not neutrinos.

    Maybe the 4 fundamental interactions have slightly different speeds and neutrinos are limited by the weak force or gravitation “speed limit”.

  • fluidic

    If i were to believe the constant speed of light and that nothing can travel faster according to GR theory, then light photons must have a velocity profile. It is absurd to think that a photon when emitted from a light source kicks off with an initial speed C(sub0) equal to the speed of light !!! such is not scientifically sound with the massless photon dilemma. Then, a photon must have acceleration profile as well! Waooo! so where are we now? the big question is where on the geodesic of a traveling photon, does a photon reach constant speed to satisfy GR theory? Also, does constant speed decay after what length on the geodesic or after what time? or it never decays? and travels in space time indefinitely ? do we have real solid answers to these questions ?

  • carlos

    Thank u very Pauline, i tried to calculate the “time advantage” of this “missing” 1987`s tachyonic neutrinos according to the OPERA result, but realized that it should be with Lorentz eqs, and i don’t have the same skills than years ago.

    Running to read the link. Thx

  • Richard Wadholm

    On the Discover Magazine web site, an interesting point was made – if neutrinos really do travel 60 nanoseconds faster than photons, then they should have arrived nearly four years ahead of the light coming from Supernova 1987A – which was emitted by a star 116,000 light years away.

    That didn’t happen. Have the rules of physics changed in the last 25 years?

  • Paul St Clair Terry

    Einstein was one of my boyhood heroes, my having first read his book on special relativity at the age of 14, testimony to the clarity and simplicity of his explanation to a general readership. It became clear to me over the following two or three years that many of his ideas were critical milestones on the road to quantum theory and when he later seemed to have such issues with Niels Bohr and the Copenhagen interpretation, I could not understand why when quantum theory seemed so clearly to be the extension of relativity to existence.

    So much of humanity’s thinking over the past two millennia has considered the nature of external reality and its relationship to mind. Kant et alia should be elementary reading for mathematicians and physicists seeking insight into the meaning of relativity and quantum theory. In naive terms, I suppose one could ask the question, “Is my observation (of some presumed independently existing thing) the thing itself or is it a representation, i.e. the way I am able to conceive of that thing?”. Of course, we cannot know and perhaps it is useful to construct terms which distinguish between these possibilities. I like to reserve the word “existence” to describe that which is being observed or “realized”, and the word “being” to refer to its presumed continuity when not being observed or realized. This definition of terms means that existence is relative, something only “exists” using this terminology when it is being observed. Our assumption of the continuity of “being” is necessary to give coherence to our observations: in that much mentioned forest where the tree apparently falls unobserved and we only see its initial and subsequent state, the falling of the tree and indeed its continued independent “being” are necessary but unprovable assumptions which make our observations coherent. I suppose that this is a sort of empiricism and it certainly colours my perspective in both theoretical physics and metamathematics. In this universe, our understanding is limited to the directly observed or the presumed effect of the unobserved on the observed.

    Einstein so beautifully made us understand that our laws of physics are of observations from the perspective of the observer but seemed not to come to terms with the logical extension of these ideas to reality. The language of (relative) existence is that of the finite, the discrete, the countable, the bounded, the localized, the particle, while the language of being is that of the non-finite, the uncountable, the continuous, the bounded, the non-localized, the wave. Limitations to what we can know, prove or understand in this second context are not peculiar to quantum physics: parallel limitations exist in metamathematics and linguistics as evidenced by Gödel and Wittgenstein. Actually, it goes beyond this – not just something we cannot know or prove but something which is fundamentally and intrinsically unknowable and unprovable. Elementary particles are only elementary particles when they exist, i.e. when they are realized or observed. Thus, the electron diffraction experiment which produces an Airy pattern even when the electrons are being fired singly is consistent with the electron behaving as a wave (with all that that entails) until it is observed and localized when it hits the screen.

    The EPR thought experiment which was decisively resolved by Bell is, as Marcel eloquently notes, indicative of the cohesion between relativity and quantum theory though, sadly, Einstein did not formulate it with this is mind. As I indicated in an earlier post above, non-locality restores the natural notion of simultaneity which otherwise might have appeared to be a casualty of special relativity. As regards quantum tunnelling, I prefer to consider this to be a consequence of the being-existence dichotomy which is how I interpret the Heisenberg uncertainty principle. I suppose that I am more aligned to the Copenhagen interpretation than to Von Neumann.

    My feeling about our quantum universe is that this is not beset by intrinsic randomness but rather is a place which is relatively predictable but with sufficient “wriggle-room” to allow the cumulative accretion of complexity and, on a human level, to allow free will. I believe that Einstein and Bohr could and should have converged on this interpretation of quantum theory as an inevitable extension of relativity. Perhaps it was a German-Danish thing which prevented consensus…

  • Paul St Clair Terry

    It may seem to conflict with common sense, but no, the photon does not have an acceleration profile. If I am standing still and you are travelling past me at a speed of 99.9% of the speed of light and a photon passes me at the speed of light, it passes you at the speed of light also – this you will appreciate from special relativity. Now, if you accelerate at any finite rate, you will never reach the speed of light and light will always pass you at the speed of light – the gap will never lessen. So, the only possibility for a sub-light-speed photon to reach the speed of light would be if it could accelerate at an infinite rate, then it would reach the speed of light instantaneously. The photon thus does “start” its journey at the speed of light in your scenario. Here is something to consider – time-dilation means that when I observe a photon, its observed state is timeless – time has stopped. If this is so, then intrinsic change in this observed state is no longer possible…

  • Paul St Clair Terry

    Bill, I am not sure that I agree with you: if these neutrinos were travelling forward in time, surely they would arrive late, not early! I think David is correct that arriving early is equivalent to travelling back in time… Travelling forward in time de facto is not inconsistent with relativity – consider the twin paradox.

    I believe that, eventually, some resolution of these experimental findings will disprove superluminal velocities but perhaps that is because I believe that things happen rather than unhappen and that history accumulates rather than undoes… Anything else is akin tio the ultimate trivialization of the universe…

  • Paul St Clair Terry

    In reply to your question, Richard, yes, the laws of physics undoubtedly have changed in the last 25 years and will continue to change over the next 25… Of course, your question really was “have the implicit laws which appear to govern the universe changed in the last 25 years?” Well, that really is an interesting question… It is fundamental to our consideration of the nature of reality that this is not limited by time and therefore is not subject to change but perhaps the “laws of the universe” are, like the cumulative development of complexity, subject to evolution…

  • Tyler

    could the earth moving, solar system moving, space expansion have anything to do with it? i would say no, relatively speaking if something traveled at the speed of light. but something traveling slower than light would allow time for everything around to move right? i’m probably wrong, but just throwing that out there!

  • Math Bollen

    Thanks Pauline for the explanation.

  • Marcel van Velzen

    @Paul St Clair Terry

    Hello Paul,

    Thanks for you profound monolog on current state of the philosophy of physics. It doesn’t make an easy reading but I fully agree with everything you write. Nevertheless, it is appropriate if people start to think about particles that travel faster than light to start such a philosophical discussion.

    It is indeed a pity that Einstein did not live to know the outcome of the EPR experiment and the formulation by Bell (I think Bell equalled Einstein here in genius). I’m glad you are not ignoring the EPR result.

    Just to add one thing:

    Physics can only describe the observed reality, it will never be able to explain it.For what should the final equation be? It can not have physical constants because why then do the constants have the value they have. It can not even have a structure, because than you could ask why does the final equation have that structure. The only escape I see is that everything is possible but maybe we are not smart enough to understand nature (like dogs are not smart enough to understand quantum mechanics) or there is some other explanation that we haven’t found yet.

    But we are getting out of topic and I’m also sorry for Milo who will never ever dare to ask another question 🙂


  • Paul K


    This is probably a very obvious question which has been taken into account but here goes anyway! If GPS is being used, has the (very small) time dilation experienced by moving satellites relative to the Earth-bound atomic clocks been factored in, or is it something which would not even cause an issue in the first place?


  • Felipe B.

    I think your answer can be a little misleading. To the neutrino in his own frame of reference, time tics at the same rate but distance (the LHC lab)shrinks. For us in the lab the neutrino time slow down. Time is the same for the own frame of reference (because in our frame of reference we are not moving). Only when are moving respected a un observer THIS observer see us like our time time were slowing down.
    Is that right?
    Of course the physics, have considered -in this pariticular case- rotation of the earth, difference between latitude from the point of departure and arrival (for the gravity effects), moon tides, etc.

  • Paul St Clair Terry

    @Marcel van Velzen @Milo Wendt

    Hello Marcel,

    Thank you for your words: it was indeed something of a monologue which I attribute to writing it at 03:30 in the morning (UK time) unable to sleep due to a painful back injury and an excessive intake of mind-bending analgesics. Apologies! Still, I hope that Milo – and anyone else – will not be put off from continuing to ask questions. Curiosity is a fundamental human trait and I encourage it!

    I remember explaining relativity to one of my oldest friends when we were both at school. We subsequently went to the same university and would regularly congregate with friends to consider “Life, the Universe and Everything”. After graduation, he left for CERN where he worked for many years. The LHC was his last project before moving to Oxford where he is now an esteemed professor. He surprised me recently by telling me that he still has the notes that I gave him at school though, thankfully, he did not embarrass me by showing them to me! Clearly, I was ever opinionated in these matters, sharing my views and ideas with unjustified confidence! I am duly chastened…

    Bell, of course, was also at CERN before taking a sabbatical to work on the EPR paradox. I do not think he was ever truly reconciled to his subsequent findings, being of a similar opinion to Einstein regarding “spooky action at a distance” and I differ from him in that regard. Like you, I consider the EPR experiment absolutely consistent with an integrated theory of relativity and quantum theory and extremely significant…

    I will try not to venture too far off topic but, in a sense, the question of superluminal velocity is strongly linked to the underlying theories of relativity and quantum reality. Though I am of the opinion that the OPERA experiment will eventually be resolved within current theory, it is always healthy to consider all possibilities. I suggest that, like Lewis Carroll’s White Queen, we should all consider “six impossible things before breakfast”. Superluminal velocity remains for me a logical impossibility so definitely something to chew over with a glass of orange juice and an espresso…

    I think any theory of “everything” will be a theory which encompasses the inevitable limitation on what is knowable given that ours is the world of phenomena and perception and so will be a theory of “everything as we observe it”. This not a question of how smart we are – we could be the smartest puppies in the universe and the unknowability of certain things would forever be there!

    🙂 Thank you again for fuelling our quest for ideas and answers!

  • fluidic

    While Newtonian motion does not mecessarliy apply in femto and quantum dimensions, its mechanistic architecture may apply. The photon must exit atomic structure due to the application of some atomic or nuclear force. This force must

    (i) realize a change in velocity of photons from zero to c in femto dimensions (within the atomic structure before it escapes) unless the photon was already at a velocity c inside the atomic or nuclear structures before ejection!

    (ii) Assume photon was at velocity c inside atomic matter before leaving light source. This is very interesting because then quantum energy levels must themselve be the spinning or orbiting photon with angular velocity = c so, when escape velocity occurs, it occurs at c and continues its geodesic after escape with velocity c. With this we would start rewriting quantum physics.

    (iii) For a traveling photon, our experiments do not measure neither initial velocity, nor terminal velocity, but measure the nanoseonds time interval between them which kills the results, because we have no technology to measure either. So, c the measured speed of light is an average speed of traveling photons, taking into consideration its initial, its in between, and its terminal velocity, and treating it as dimensionless, timeless, and psuedo-Newtonian.

    So fortunately, there is both photon velocity and acceleration profiles. And yes! given the above reasoning, we could think that there are neutrinos or other particles that travel faster than c. Scientist will one day observe that anti-electromagnetic radiation including photons must travel faster than the observed light speed c. Its function is to eleminate photons so that nature and the universe do not get steadily and increasingly brighter but remain with almost steady illuminosity.

  • carlos

    Really nice the Matt’s site. Thank u for feeding my curiosity 🙂

  • Josef Riedlberger

    I want to add to my previous comment a more clear description of my concerns of the clock synchronicity.
    It is important to mention that the paper relies on the clock synchronicity from the GPS system (PolaRx2e) essentially by reference to the crosschecks from the Swiss METAS and German PTB experts, furthermore they claim that the technology is commonly used for high accuracy time transfer applications. I guess that is all correct as this systems should be consistent within itself, which means they are tuned to the velocity of light in air. They never encountered a situation where you have to extrapolate to vacuum. The “same time” in usual applications refer to the light cones with a light velocity in air.

    Looking at figure 5 of the paper and the triangle CERN, LNGS and GPS Satellite: Certainly, if the satellite is exactly symmetric between CERN and LNGS it would not matter what the speed of light is for the communication Satellite-CERN, Satellite-LNGS.
    Let’s for the example collapse the triangle and move the Satellite to CERN. It sends a signal with time stamp zero to LNGS, which accepts this timestamp and after an accurate known delay send it back to CERN. Subtract this delay from this double flight time one can use the flight time to calibrate the LNGS. Both systems would now be accurate with respect of the velocity of speed in air. And consistent with any other GPS station. I would be surprised if the GPS system would always use the virtual vacuum time delays and correct every time back and forth.

    For the neutrino experiment, however this calibration is not valid, as the flight time would be shorter in vacuum (the vacuum pipe I mentioned in my first comment). So the clock at LNGS should not be aligned to be synchronous with GPS applications but adjusted with a shorter time-of flight. Otherwise the clock would be late. A late clock would lead to a faster arrival time measurement of neutrinos. In this worst case the effect could be 731km/(299 792km/s)x0.0003 ~ 730ns clock delay. [1.0003 as refractive index of air].

  • Adam

    Hello Pauline,

    From what my wife says, MINOS will not be capable to see the result. Nor any existing experiment (including her own T2K). Of course, MINOS has the potential, but their signal is too weak to be assumed “proper”. I guess we’ll have to look for the systematic errors to be sure. My personal favourite for the error (if any, of course) is the distance measurement. There’s plenty to check there including for example distortions made by Earth rotation or assumed trigonometry. After all, assumed effect of 60/million is equal to something like (more or less) 40 meters. And detecting a small relative movements says nothing about how good the base distance measurement was.

    Thanks for answer on inflation, got it much better now.


  • Adam

    One more correction – it’s 60ns of course, not 6*10E-7 of whole time, so the distance is smaller, assuming c=3*10E8 m/s and deltat=6*10E-8s it gives something like 18 meters difference.


  • Adam

    @ fluidic: Aren’t you too much into looking at particle?
    What if we changed it into electromagnitic wave – does it require acceleration?
    If we assumed the light (as a wave) is emitted due to energy provided, and movement of particles (electrically charged)?
    And I’m not a physicist, so probably the model is still way to simple.

    I guess there’s more to that than just a particle crash and photon creation. Not in the way you are thinking they are.


  • Pauline Gagnon

    Hello Jacek,

    at this point, all this is pure speculation. We are not even 100% sure neutrinos travel faster than light! Of course, it is fun and tempting to think of the implications. Figuring out all the details is now the big task awaiting all those involved in this. If this is confirmed, then theorists will get to work to find an explanation that fits the experiment, Then, we will know if there is a difference, and, second, we will need to figure out why this difference is the size that is measured.

    Lots of interesting work ahead!

  • noname

    No. Just no, fluidic. Please read up on quantum mechanics. Your confusion is too deep to address fully in one blog comment.

  • Tim


    I’m not a physicist and only have limited knowledge. The speed of light is measured as two way. Meaning light is reflected off a mirror back toward the source and a measurement is taken. With this experiment, it is a one way measurement of speed.

    Nanning commented earlier that the rotation of the earth could be moving the finish line toward the start line and the reply was that this had been checked and the difference would be too small. Was the rotation of the solar system, rotation of the galaxy and also the speed that the galaxy is moving through the universe taken into account.

    In a two way measurement of light, the light may take a shorter time to reach the mirror than it does to return toward the source but as only one measurement is taken then all we get is an average of the two directions of travel.

    This little planet of ours seems to be moving at a fair speed through the universe. I have no doubt about the calibration of the experiment and now that it is possible to do one way speed test with this degree of accuracy it may be an idea to re-visit the speed of light measurements.

    Just my thoughts


  • fluidic

    noname: you could have all my sympathy for your simplistic and conventional view… it will be impossible for you to explain how and when matter emits light due to changes in energy state or energy levels in the form of electromagnetic radiation, our photon starts with an initial velocity = c? quantum theory is one of the greatest achievements of our times, but unfortunately keeps stepping on its own feet because of its disconnectedness and the failure to connect its pieces solidly. While quantum physics is a great achievment, its standard model is in a depression and is a great failure. Reason: many individuals maybe like yourself have invested lots of time, governments have funded lots of machines like LHC… to try to find NOW that we are on our way to disprove higgs boson, and prove its inexistence: contrary to what we were trying to achieve. Most interesting though when you hear people say the greatest achievement is, we have been able to prove after 30 yrs that the higgs boson does not exist.

    Good for you, and best of luck.

  • 60ns is 20m. So, I would look for a 20m discrepancy. I notice that the target is a 20m tall curtain of scintillator “bricks”. I also notice that earlier this year, a better discriminator (multiple coulomb scattering) was installed in the portico at the OPERA experiment. I speculate that perhaps the older discriminator used 20m fiberoptic cables, and that the data acquisition program accounted for that 60ns delay. If the newer discriminator relies on microprocessors local to the scintillators, that apply a time stamp at the time of scintillation, then that 60ns delay no longer applies. Perhaps the data acquisition program has not been corrected?

  • I think there must be a mistake made in the experiment. No particle can travel faster than the speed of light.

    Any particle that travels faster than the speed of light (a tachyon) can be used to send messages backward in time, with all the consequent paradoxes. A reference frame traveling sufficiently fast in the same direction as the tachyon will see the tachyon traveling faster than the speed of light in the opposite direction. Reflect the tachyon, and the start and end point end up on the same time-line, but with the start point later in time than the end point. I don’t think that a path of least action can be found for such a particle: quantum mechanically, its wave-function would cancel itself out.

  • fluidic

    since we are speaking about the possibility of existence of particles or radiation faster than c, we might as well throw here a very intriguing question. electromagnetic radiation we know travels in sinusoidal wave-shape motion, could it be that its real motion is helical in 3D space, but whose orthogonal projection on 2D plane (plane we observe and analyze) is perfect sinusoidal wave, so that all mathematics and physics of electromagnetic radiation on waves remains the same, unchanged. But we have the advantage of analyzing its true natural face in 3D, a dimension we have not been able to see or detect even in quatum electrodynamics within the General Relativity of spacetime curvature?

    It could make sense since then, we could explain when a photon or electron leaves atomic matter, how its helical motion starts initially with a spinning and continues helical throughout the photon journey.

    It is very hard to prove or disprove.

  • I understand that an experimental design has, under the explicit assumptions, many hidden. I understand that it is wrong the hypothesis relativistic for which the travel speeds of the bodies must be minor or equal to the propagation speed of the scan signal.
    It is showing a vertiginous theoretical empty now, because the experiment shows that Lorentz Transformation and Relativity Theory are not correct. This obliges to reconsider decisions taken over a hundred years ago.
    In one example: classical calculations of Michelson-Morley experiment provided a non-zero result (0.4), but these estimates are poorly performed (http://espacioytiempo.net/ in / Recalculating-Michelson-Morley /).


  • Cristian Fernández

    Long ago I read in a physics book that the expression m=m0/SQR(1-v2/c2) was verified, confirmed, everyday at CERN accelerators. But since all the accelerated particles are charged, How do you know it is not the charge what
    is decreasing with the speed, i.e. q=q0*SQR(1-v2/c2)?

  • Josef Riedlberger

    In have to correct what I have written: only if there is a systematic difference of the time of flight between sending a signal from the satellite (going from thin to dense medium) and receiving a signal (coming from dense to thin medium) a wrong clock could happen. However it would still be cancel between CERN and LNGS, unless the density of the air at the Mont Blanc is significant different (a time bias depending of the refractive index).

  • The problem of postulating that light is an absolute (as the zero Kelvin) is that if this postulate is false, every theory of physics phenomenology is also wrong. In particular has an important consequence regarding the OPERA experiment: to postulate that the speed of light is absolute maximum speed and invites you to take as a reference and standard clocks. The clocks are based on a comparison of movement, which has another consequence, because the speed of light “if it is dependent on the velocity of the observer” (Physical Theory of Place), and therefore the relativistic postulate produce inaccurate clocks. When sophisticated experiments are not light-dependent (such as atomic clocks), these results show that relativistic does not match the experimental resultants: OPERA has proven so. The speed of a signal, whether it is, can not be taken as a clock pattern without considering the relative movement of the observer. I estimate this condition as “lost area” Every observer is bound to measure the same speed of light regardless of their relative motion, but nevertheless, this does not happen physically: the facts outweigh the visual literature (It can be fun to read: http:// / espacioytiempo.net / en / the-lost-zone-and-the-end-of-the-world /)



  • Rosemary

    I’m a high school student studying chemistry (I took physics last year) and I was of course very excited to hear about CERN’s new discovery. My dad and I came up with a theory that there might actually be different speeds that light travels at. If this is plausible, then the neutrinos weren’t actually breaking the fastest speed of light, simply the speed of light that we see as a standard (and have not challenged).

  • Pauline Gagnon

    Hello Christian, we know the charge does not change for many reasons. We measure the curvature of charged tracks in one part of the detector (tracker) and the associated energy deposit in another part (calorimeter). For example, for an electron, we would see that the curvature would change if its charge changed. This is not observed. On the contrary, the momentum inferred from the curvature corresponds to the energy measured in the calorimeter for a track of charge = 1. So we know the charge does not change. But we see the mass changes.

  • Pauline Gagnon

    Hello Rosemary,
    there are all sorts of theories being put forward right now by theorists to try to explain this. One possibility is indeed along the line you describe. Some people think the real limit might not be the speed of light but speed of the neutrinos, if indeed this proves to be true. But there are so many chances this could be due to an experimental error that it is too soon to speculate on what might have caused it. If other experiments confirm this result in many different ways, then we will need to think how to fit this in.Your idea is one of the many possibilities being proposed right now.

  • Ziad Khalifeh

    Hello Pauline
    Did the OPERA experiment take into precise measurement the time elapsing for experiment components such as the physical structure of instruments used in performing the measurements : time for electronic signals travelling through the cables from detectors to computers, length of cables, quantum realities in the chips of computers and PC processors, and those in the GPS satellite instruments, etc … Also, I have a vague thought, since I am not a physicist, what about the relativity of time concerning the speeding of particles at CERN, wouldn’t they be the future of our time at OPERA when the particles collide to produce neutrinos ?

  • I propose a hypothetical scenario: What would happen if the human species was blind but not deaf?: One would conclude with a Bat Relativity, to impose the sound speed as the maximum of the universe: This is the “characteristic limit” of the “Physical Theory of Places” : the universe faster than the speed of the exploration signal does not exist for the observer (http://espacioytiempo.net/en/)

    My disagreement with the Theory of Special Relativity was due not so much by the literalness of the second hypothesis, but because it implements the Lorentz Transformation and it appears as a never explained result the “singularity” relativistic that, indirectly, suggests that it is not possible superluminal speeds (that also it would cause a disproportionate increase of mass at approaching light speed).

    On above hypothesis it is added for free the assumption of a “physical vacuum” that would slow down the chance to travel faster than light “: this seems a contradiction because it raises the question of what quality must have this vacuum to put a limit on the speed of the bodies.

    I think the Relativity Theory is a beautiful song that incorrectly wants to rise to the absolute limits of the universe, but I think more accurate to quantify the distortion produced by the propagation of signals (including light), and clearly establish the distinction between the image that these signals provide and the physical of facts observed.

    So what prevents that something travels faster than light: The vacuum? A human theory?… Or a phylogenetic and technique limitation to observe bodies traveling faster than light: Things were so until now.


  • Oyvind Aspen

    When can we exepct the next atempt on this accurante experiment? And does the result contradict the reality thoery as we know it today? I see here in the answers you where given that you disagree with general relatity theory, special that part where there is a incohorence between second hypothesis and the Lorentz Transformation. Does this mean that you think it is possible for a particle (like Neutriones or Higgis) to go past the limit of ligth? Doesn’t that implicate that these particle will past the time barrier as well?


  • I understand that the time doesn’t exist in the physical universe, like one won’t find one dollar inside any ingot of gold. The time and the dollar represent other things. Time is not a physical entity; it is an exercise of the memory for quantifies the “order of events” (Leibnitz). The fundamental physics units should be the space and the speed. If one interprets the time like ontic and fundamental unit of the physics, one grants to this concept causal quality. Slipped down by this way, one finishes formulating convinced that what is derived of those formulas represents the Physical Reality. The ‘derivate unit’ of the space and time relationship is the speed (v=s/t). As the Transformation of Lorentz has been thought right, one end up believing this formula represents the physical reality; but the Transformation of Lorentz forces us to think that the universe has limited the absolute speed by light, because this formula relates the bodies speed with of the speed of exploration sign: that is to say, ‘c’.
    However, if time is understood like a derived unit (t = s / v), we would conclude with “transformation of place”, and light speed could never be considered as an unbeatable limitation, although it could be considered a pattern of speed. The time cannot be constituted as any physical barrier, neither it is possible the return in the time. If the universe puts limits to the speed, these cannot be derived of the contingencies of the exploration sign but if if celestial players play tennis before us with balls that traveled quicker than light, we would not see the party.

  • Oyvind Aspen

    If I understand you rigth: This postulate that it is impossible to for instance to travel in time. Because times is not a physical entity. Dosn’t that contradict the theory of hypespace like S. weinberg and other physicist have proposed as solution to a “final theory”. That theory indactes the possiblilites of a time travel.

  • Oyvind Aspen

    Is there any serious atempt to make a similar exeperiment as OPREA in near future? Dosn’t USA have some capaicity to do some similar exeperiment? In the science community at Cern is there scinetist who propose the possibilty that particle travel faster then ligth is equial to time travel? I am familar with Einsteins theories, but have scinetist at CErn claim that travel faster then ligt is equial with travel in time? What about physicist Tom Weiler at Vanderbilt University who claim that the particle Higgis singlet can travel in time? Is that suitable theory that can substain the Opera results?

    best regards
    Oyvind Aspen

  • Marcel van Velzen

    The neutrino experiment has been brilliantly repeated by CERN with short pulses which confirms the original conclusion. So the statistics was right which is pretty impressive. This new result shows how marginal the result is. The time shift of 60 ns is about equal to twice the standard error of 30 ns. I have read the whole Opera paper carefully and have no idea where there could be an error. Although I still think the result is wrong, if no error can be found in an experiment it is correct to send the paper to an official journal for publication. Great work!

  • Mark Hoffner

    When the OPERA apparatus was built I’m sure it was to very precise specifications carried out using laser based survey equipment. Now, according to relativity, the baseline distance of the apparatus was laid out along the curvature of a geodesic of the space-time continuum as defined by the movement of a massless photon moving through the Earth’s gravitational field. Further, when a neutrino is fired toward the OPERA detector, it is assumed that it will travel along the same geodesic as defined by the previously mentioned photon .

    My hypothesis is that the mass of the neutrino interacts with the Earth’s gravity field causing it to travel along a less curved geodesic than the photon travelled. It is my belief that the data will allow us to precisely compute the underlying space-time curvature of the Universe.

  • Francis Farley

    How come nobody mentions the paper by Ronald Elburg arXiv:1110.3685v4 showing that if both clocks are synchronised to a satellite it is really the satellite clock that is making the measurement? The neutrinos travel at velocity c relative to the observer, in this case the monkey in the satellite. As Gran Sasso is moving towards the observer the neutrinos arrive there sooner. Elburg claims that this correction explains the observations perfectly.

    To synchronise the clocks, why not carry a rubidium clock in a car from CERN to Gran Sasso and back. No satellite, no need to know how high the satellite is as it passes each station to better than 20 metres, etc.

  • Francis Farley

    Errata Elburg’s paper is arXiv:1110.2685v4

  • Francis Farley

    Sorry folks, reference to Elburg’s paper was mis-typed, it should be arXiv:1110.2685v4

  • I have to agree with Oyvind was it not us (man) that decided time as shorley prior to mans existence time did not exist within reason. http://www.azlan-eu.co.uk so would it not be accurate to say time travel is just not possiable. Just a thought.

  • Jim Goodman

    It is possible that a neutrino is a magnetic dipole and a photon is an electric dipole. That might explain why neutrinos travel farther into matter than photons(photon potential = 13.6/r and neutrino potential = 13.6/r^2) Also the neutrinos would travel faster as a result of less interaction.

  • Atif

    I am a biotechnologist.And I also keep interest in particle physics.
    Can this experiment prove the existence of parallel realities and other dimensions?