CERN claims to have measured particle that travels faster than light

Big and controversial science news breaking today, via AP: "A pillar of physics — that nothing can go faster than the speed of light — appears to be smashed by an oddball subatomic particle that has apparently made a giant end run around Albert Einstein's theories. Scientists at the world's largest physics lab said Thursday they have clocked neutrinos traveling faster than light. That's something that according to Einstein's 1905 special theory of relativity — the famous E (equals) mc2 equation — just doesn't happen."

BBC News has a somewhat less breathless take here. More at Ars Technica, and Wired News.


    1. Based on what I’ve read, they ran the experiment 15,000 times. They are now asking other physicists to verify it, so of course this result may change.

      1. I’m not sure they ran the experiment 15,000 times, just that they have 15,000 measurements.  Could be 500 measurements per experiment, for all I know, for a net of only 30 trials.  “The team measured the travel times of neutrino bunches some 15,000 times”

        1. The real question isn’t the sample set, it’s the number of devices the experiment was run on. I believe it stands at one.

          1. Good point.  As the article points out, that’s why they’re publishing – so that other people can run the experiment elsewhere.

          2. Unfortunately particle accelerators and their associated detectors aren’t easy to come by. In the whole world, there’s less than two dozen neutrino experiments going on right now. I believe not all of them are suitable for this kind of experiment.

            It’s more about narrowing probability anyway. They’ll pour over old data again and again even as they collect new data, refining their results until they figure it out.. either as an error in the experiment, or a new discovery.

  1. conCERN, sometime#

    ” Oi! _ can someone bring the torch and the Timex watch. We have to check out those horrible wee rapids with that funny name … and bring a reading-glass too … spasiva. “

  2. Extraordinary claims require extraordinary evidence. I’d wait a few months or years for more experimentation before declaring Einsteinian physics dead. 

    One of the weaknesses of reporting new discoveries in esoteric corners of bleeding edge science like this in the mass media are jumps to conclusions. The blind leading the blind. 

    1. But neutrinos have a nonzero mass, right?

      So they say, pace John Updike:

      Neutrinos they are very small.
      They have no charge and have no mass
      And do not interact at all.
      The earth is just a silly ball
      To them, through which they simply pass,
      Like dustmaids down a drafty hall
      Or photons through a sheet of glass…

    2. Possibly zero rest mass, but non-zero momentum, and effective mass.

      “The Standard Model of particle physics assumed that neutrinos are massless, although adding massive neutrinos to the basic framework is not difficult. Indeed, the experimentally established phenomenon of neutrino oscillation requires neutrinos to have nonzero masses.”

  3. I have this mental image of a neutrino, pulled over at the side of the highway, and the officer asking, “Do you have any idea how fast you were going?”

    1. Actually, given this neutrino, it’s probably more along the lines of the police officer saying, “Do you have any idea how fast you were going?”, as the neutrino speeds past him.

  4. I think your headline is a bit misleading. They’re not really claiming anything per se.

    “My dream would be that another, independent experiment finds the same thing – then I would be relieved,” Dr Ereditato said.

    But for now, he explained, “we are not claiming things, we want just to be helped by the community in understanding our crazy result – because it is crazy”.

    Also the article is wrong about where the speed limit in special relativity comes from. It’s an assumption used to preserve causality, but no one has identified a natural mechanism that leads to the speed limit. Special relativity tells us why it’s very hard to accelerate something to the speed of light – the Loretnz factor used to calculate momentum would approach infinity, meaning an object would need infinite energy to travel that fast – but that’s not directly related to e=mc^2.

    1. Exactly.  As I understand it, special relativity doesn’t say that a particle can’t travel faster than light – only that a particle can’t accelerate or decelerate through the speed of light.  Thus, a particle traveling faster than light could not slow down from above the speed of light to below it.  I think the challenge is that a particle traveling faster than light could be viewed as traveling backwards in time, which presents it’s own issues.

      1. Relativity says that the mass of massive particles traveling faster than light becomes the square root of -1, which is the set of imaginary numbers.

    2. Not just approach but asymptotically so. So that unless there’s new physics involved, all the energy of the CERN accelerator applied to a single neutrino would be insufficient to accelerate it to c.

  5. I’ll have much more faith in this once it’s been verified, and once Maggie vets it (you know, the Science Editor).

  6. From what little I know about special relativity (and I’m no scientist) there’s no law that says things can’t travel faster than the speed of light BUT (under the framework of special relativity) it is impossible for something to break the barrier from sub-speed of light to faster than speed of light.

    The skeptic in me says maybe this is a problem with the equipment at CERN? Haven’t the fucking magnets broken before? How do they work? 

    But it would be really cool if Gaeta just gave the order to spin up the FTL…

    1. It says that the barrier can’t be broken either way, basically. You can’t accelerate past it; if you’ve started past it, you can’t decelerate below it. All asymptotic and shit.

      The problem is that I’ve never heard of superluminality in the context of something with mass. As far as I understand, it would take an infinite amount of energy. This is of course the way physicists and mathematicians say ‘….no‘. Photons can travel at the speed of light because they have no mass. Also because they, well, are light.

      1. So, can a particle tunnel (blip out of existence and back again, sort of like with Hawking radiation) to a different speed so long as it has the same energy? Is there a speed above c where the energy (and momentum?) of a particle corresponds to the same energy (and momentum) of the particle below c?

        And no, I’m not saying there’s a worm hole in the middle of the earth.

    1. I see what you did there, but sadly, your irony fails. There’s something called “relativistic time dilation” (and yes, it’s been proven experimentally), Given a spacecraft that constantly accelerates with 1g (you know, just for that cozy, heavy feeling of earth-like gravity), travellers could actually reach every place in the universe within their lifetime.

  7. I’m halfway through reading Understanding Einstein’s Theories of Relativity by Stan Gibilisco.  Thanks for nothing, CERN.

  8. Everything else about Relativity has stood up well for 70+ years of testing.  It would be surprising if one important aspect of it was suddenly disproved.  In any case, the scramble to reproduce CERN’s results should be interesting.

    1. 70 years isn’t very much time to attack a theory, especially when it’s a theory that gets beaten more and more into you the further you get into studying physics.  And who wants to throw away money funding experiments to disprove something we’ve all known as “fact” for our entire lives?

      That’s like saying it’s surprising we humans actually got off the ground after a few thousand years of knowing it was never going to happen.  Not surprising– inevitable.

      [This is what happens when we start telling students that evidence ‘proves’ theories.  Shame on you, Science, you did this to yourself.]

      1. “[This is what happens when we start telling students that evidence
        ‘proves’ theories.  Shame on you, Science, you did this to yourself.]”

        What in world are you talking about? This is exactly what science is, and if anyone is teaching that science gives absolute answers they have kind of missed the point. Science is about putting forth hypothesis and then testing them to failure if possible. That being said there is a lot of room for something else to be happening like instrumentation issues that must be ruled out before we start working on warp drives.

      2. “Evidence proves theories”.

        In science, none of these words mean what they do in common English.

        Evidence – experimental results with high significance.

        Prove – test. Consider “proving ground”, “he has to prove himself”, the baking use of “prove”, etc.

        Theory – a demonstrable fact. Evolution, gravity. The cause is hypothetical and a possible subject for research, but the effect is a fact.

        A literal translation to common English would be “experiments test known facts”.

      3. The only thing that is inevitable is bad news, like death. Extinction probably was more likely than man learning to make flying machines.

  9. Relativistic addition of velocities is baffling.  0.9c + 0.9c =~ 0.92c apparently.  If the speed of light is the speed of time, what does that say about these particles’ ‘local’ clocks?  Nothing that Relativity can tell us.

  10. I think this article and the comment thread is a positive example of science in action. Many of my friends believe scientists conspire to protect their dogma, but here we both have excitement to overthrow (” I doubt it is true, but if it is … cheer! New science!”) and a honest admission of confusion and desire to be challenged, “Help us figure out wtf is going on…”). Everyone is excited, open minded, and skeptical at the same time.

  11. I don’t really understand.  But I can share with you that I had a fantastic steak for dinner, and it went down faster than the speed of light.  No need for $999 zillion bits and bobs really.  The proof’s in my tum tum.

    1. Not surprising your steak went down so fast.  It’s because the speed of light can be exceeded by mootrinos.

  12. I’m not sure that this is all that surprising. It does not invalidate Einstein’s theories, it merely could take our understanding one great step forward. In turn, Einstein did not invalidate Newtonian mechanics, he merely expanded the scope, explained already measured phenomena, and predicted many other phenomena. Such measurements, if proven to be correct, will spur young Newtons and Einsteins to think out-of-the-box, and come up with new ways to look at the universe. It’s about time we began moving forward, past this, and looking for the next, more refined theory. In fact we must do this if we are ever to get off this planet and reach for the stars.

    1. “It’s a shock,” said Fermilab head theoretician Stephen Parke….  University of Maryland physics department chairman Drew Baden called it ‘a flying carpet,’ something that was too fantastic to be believable.

      Man, if you seriously do not find this surprising, you should be applying for a job at Fermilab…  or an Apple genius bar.

      1. University of Maryland physics department chairman Drew Baden called it ‘a flying carpet,’ something that was too fantastic to be believable.

        He later revised said statement after a snarky colleague reminded him that most commercial aircraft have carpeting.

        1. “In a revised statement, University of Maryland physics department chairman Drew Baden said it was ‘like seeing a man eat his own head,’ something that was too fantastic to be believable.”

  13. What one might immediately overlook, but instead came first to my mind is this.  Things work VERY differently at subatomic/quantum levels.  The same way I assume they will one day find out is true in a massatomic level- meaning in the extreme vastness of space/time or any extreme density of mass like a collapsed star or black hole. Our world of well defined physics will barely apply there.

    It is a known fact that there is a very strange and unexplainable group of things that happen in ultra small/quantum applications such as in the “Double Slit Experiment.”

    It has always been my assumption, even since childhood, that proven “physics” problems like objects and the speed of light had less validity when dealing with “quantum physics.”  It just makes sense that there are different levels with different physics.  Einsteins theory has not been truly busted in our realm of physics, being, and ability. It just doesnt apply in quantum applications.

          Instead I think there will be an adaption whereas physics will be forced into three categories, as in subatomic, atomic, and massatomic.

  14. Not sure what the original version of this is, but someone’s gotta do it.

    There was a young lady named Dwight
    whose speed was much faster than light
    she went out one day
    in a relative way
    and returned on the previous night.

  15. “The team prepares a beam of just one type, muon neutrinos, sending them from Cern to an underground laboratory at Gran Sasso in Italy to see how many show up as a different type, tau neutrinos.”
    This is for The Greater Good.

  16. 09:23:2011:00:32:ZULU

    1st axiom of travelling faster than light: “Make sure there is a star or a neon in front of you”


     — James Ph .Kotsybar

    young lady known simply as Bright,

    could travel at speeds fast as light,

    “While I’m never late,

    concerned that my weight

    to infinite mass, though I’m slight.”

  18. I’ve always been puzzled by the “invariance of the speed of light” concept.  Wasn’t the invariance of the speed of light in every frame of reference precisely what Einstein was trying to *explain* with Special Relativity (you know, the evidence of the Michelson-Morley experiments & everything)?  There always seemed to be something circular about the argument.  “Let’s just assume it *is* invariant and take things from there.”  Yes, but *why* is it invariant?  (If anyone can point me to a good source treating this particular question, I’d be grateful.)

    1. Absorption and re-emission by surrounding particles “slows” photons on a technical level, in actuality they are still traveling as fast as ever, just zig-zagging a bit.

    2. The assumption of invariance was made because the Michelson-Morley experiments suggested that might be the case. The theory was an attempt to explain such an experimental result.

  19. Everyone is still arguing particle. As I was taught, wavicle. Both. the mass is drug by the wave, wave interference, produces a rogue wave that is faster then the normal wave, dragging its particle, to a greater speed.
    Also, the wave is relitive to the motion when measured, the heinzenberg principle, you interfered with it, Cghanging it’s pattern, and position.

    1. 1) Waves don’t drag anything. An open range wave is an oscillation in the interface between non-moving media. When a tsunami travels across the ocean at 300 mph, the water molecules aren’t moving anywhere near that speed. It is the energy that is transferred that moves at 300 mph. The same is true of electromagnetic waves, which is the reason that scientists believed in the ether. Einstein pointed out that the ether could exist, though without any mechanical properties.

      2) The wave is the particle.

  20. Given the relative  interaction and production rates in neutrino experiments, 15,000 events sounds rather huge.  Great if they found something, but it sounds like it would be kind of an obvious effect that someone would have noticed by now. 

    Trigger jitter.  It will probably turn out to be something like a space heater in the experimental hall blowing on a trigger rack on days when someone left a rollaround toolbox in a certain spot.   A NIM module not correctly seated… Maybe there’s something wrong with their beam synch system…   

    It will be interesting to see what they have to say about it late next week.

  21. I don’t care, if we think, it is possible! We don’t get it all, who knows, maybe, just maybe it could be possible! please let it be possible! please please please!!!! Engage!

  22. Calculating refraction through a medium requires temporary suspension of the speed of light limit to explain the extra distance traveled as the light bends but emerges at the same time as unbent light.  This is nothing new; now the medium is just distance and the light is neutrinos rather than photons.  Big whoop.

  23. @DewiMorgan
    Thanks for pointing out this definition of “prove”.  That is exactly why people misunderstand the phrase “The exception that proves the rule”.  It doesn’t mean that having an exception makes the rule true; that would be a ridiculous conclusion.  It means that an apparent exception *tests* the rule, that it invites closer examination of both the exception and the rule, to see if one or the other needs to be modified.

    I disagree with your definition of theory, though.  In most uses, theory means a set of assumptions and rules that together seem to be a coherent model to explain how something works.  The model may be an accurate predictor of future behavior or not, which is why challenge and experimentation are so important.  For example, the modern theory of gravitation is one that has been shown to be pretty accurate, and is thus, for most purposes, a reliable model of how gravity works. Other theories may be shown to be false, and are discarded as not good models of reality, such as the theory that an invisible “ether” permeates a vacuum.  Bad theories may be discarded, but one can still call them theories. They are just not very good or useful ones.

    1. On the “exception” phrase: what you are saying makes perfectly logical sense, but isn’t the case. In its original sense, the phrase means that the presence of an explicit exception to an implicit rule implies that the implicit rule exists. That is, if there is a rule which says “Muser may walk on the grass”, that implies some sort of prohibition against someone else walking on the grass. See

      1. Very interesting analysis, thanks for the reference.  Perhaps I am mistaken about this phrase. I wonder if someone else has done a history of the other argument?

    2. The meaning that Matthew Miller points out is a legal principle that dates back at least as far as Cicero.  

      What he actually said, though, was, “the exception confirms the rule in cases not excepted” (though of course he said it in Latin: “exceptio probat regulam in casibus non exceptis”).

      If a sign says “No Parking 6am-10am”, that implies (in the absence of any other regulatory sign, of course) the existence of a more general rule that, outside of those hours, parking is permitted.

      The existence of an explicit exception to a rule proves the existence of the implicit rule that applies to all cases not excepted. 

      The omission of the phrase “…in cases not excepted” has led to all manner of confusion.  

      The ‘tests the rule’ interpretation is at least a reasonable attempt to understand a phrase that otherwise makes no sense.  The other common interpretation is ridiculous on its face and deserves only mockery.

  24. As we all know, the fastest thing in the universe is Bad News.  It travels much faster than light but has its own problems. Douglas Adams described it best: “The Hingefreel people of Arkintoofle Minor did try to build spaceships that were powered by bad news but they didn’t work particularly well and were so extremely unwelcome whenever they arrived anywhere that there wasn’t really any point in being there.”

  25. No one realy understands time, so a result that involves a discrepant time measurement is not a surprise – it really could be a new physics. As it involves a particle that barely notices what we see as the real world I dont think its any kind of gateway to FTL for anything with definite mass.Or even a threat to the Standard Model or Special Relativity. However this is the wonder of science, they are going to dig and dig and dig until it goes away as a mistake in the experimental method, or they figure out what it really means. Thats why science is fun, there is an answerr or there will be an answer one day if we keep working at it. Nothing else in the philisophical realm has this kind of satisfaction that once the password has been cracked and the tumblers fall into place we can know that what we know is valid – for the time being until all the complexity has been squeezed out of it. Science is pretty.

    1. That’s odd. It should be 4.2 meters per second faster. Science uses SI units, and 42 is always supposed to be the answer.

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