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Neutrinos Travel No Faster Than Light, Says ICARUS 112

ananyo writes "Neutrinos obey nature's speed limit, according to new results from an Italian experiment. The finding, posted to the preprint server arXiv.org, contradicts a rival claim from the OPERA experiment that neutrinos could travel faster than the speed of light. ICARUS, located just a few meters from OPERA, clocked neutrinos traveling at the speed of light, and no faster, after monitoring a beam of neutrinos sent from CERN in late October and early November of last year. The neutrinos were packed into pulses just four nanoseconds long. That meant the timing could be measured far more accurately than the original OPERA measurement, which used ten microsecond pulses. The new findings are yet another blow to OPERA's results. Researchers there had announced possible timing problems with their original measurements. For many, this will pretty much be case closed."
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Neutrinos Travel No Faster Than Light, Says ICARUS

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  • by Anonymous Coward on Friday March 16, 2012 @02:16PM (#39381381)

    I mean, what kind of a bozo looks at an unexpected result, from an incredibly complex first-one, never-been-done before kind of a machine, and jumps to the conclusion "FASTER THAN LIGHT"!

    I always assumes the faster than light shit wasn't an actual claim, just lazy reporters trying to hype up some attention and web clicks or what not.

    I'm curious that neutrinos went the speed of light at all. IIRC, don't neutrinos have mass? Shouldn't it be impossible for anything with mass to go c?

    • by Goaway ( 82658 ) on Friday March 16, 2012 @02:29PM (#39381603) Homepage

      Neutrinos do seem to have mass, and thus do not actually travel at the speed of light. However, the mass is very small (and as far as I know still unknown), which means that since they are created with fairly large energies, they immediately start moving at extremely close to the speed of light. So close that we can't tell the difference.

    • by snowgirl ( 978879 ) on Friday March 16, 2012 @02:30PM (#39381607) Journal

      I'm curious that neutrinos went the speed of light at all. IIRC, don't neutrinos have mass?

      Yes, but it's very small. For example, while the electron has a mass of about 0.5 MeV, the neutrino upper-bound has been pushed down from 50 eV, down to the prediction that the combined mass of all flavors of neutrinos must be under 0.3 eV.

      So, it's around less than a millionth the mass of an electron. This means that it can obtain much faster speeds with the same amount of force.

    • by Kjella ( 173770 ) on Friday March 16, 2012 @02:30PM (#39381631) Homepage

      I always assumes the faster than light shit wasn't an actual claim, just lazy reporters trying to hype up some attention and web clicks or what not.

      Of course that was the claim, but in a sane science to layman translation it'd be: "We have this crazy result here with neutrinos that seem to go 60ns faster than light speed. Pretty much all of established science goes against this, but we've double checked our equipment and figures and can't find the error. So we're telling you about it so someone else can run this experiment and see if they get crazy results too, meanwhile we'll triple check our equipment and figures." There's not a single scientist surprised by this eventually being proven to be just a fluke. Nor by journalists hearing "blah blah blah neutrinos blah faster than light blah blah blah", lets make a headline. Absolutely par for the course, as far as science reporting is concerned.

      • by rrohbeck ( 944847 ) on Friday March 16, 2012 @03:11PM (#39382171)

        It was mostly about metrology: "How could we have gotten this wrong?" They never raised the idea that Relativity might be wrong. The original paper was very clear and cautious about it.

        • by Kreigaffe ( 765218 ) on Friday March 16, 2012 @03:53PM (#39382729)

          Relativity has a body of proof behind it. One strange result MIGHT invalidate it, but it's more likely that were these results valid that we would've had a clue that this *could* happen before it happened. The right way to approach it is to assume relativity -- which has evidence backing it up, experimental and theoretical -- is correct, and that there was some experimental error, something systemic.

          Hey guys, this result doesn't agree with what we expected and believe true based on math and experiment. What did we do wrong?

          Likely, something was done wrong.

          In the unlikely case that nothing was done wrong and the results are reproducible, well.. THEN you start questioning relativity.

          • by ediron2 ( 246908 )

            Relativity has a body of proof behind it. One strange result MIGHT invalidate it, but it's more likely that were these results valid that we would've had a clue that this *could* happen before it happened. The right way to approach it is to assume relativity -- which has evidence backing it up, experimental and theoretical -- is correct, and that there was some experimental error, something systemic.

            Hey guys, this result doesn't agree with what we expected and believe true based on math and experiment. What did we do wrong?

            Likely, something was done wrong.

            In the unlikely case that nothing was done wrong and the results are reproducible, well.. THEN you start questioning relativity.

            Bravo. Brilliantly put.

            ObAsimov:
            The most exciting phrase to hear in science, the one that heralds new discoveries, is not “Eureka” but “That's funny...” —Isaac Asimov (1920–1992)

        • \It was mostly about metrology: "How could we have gotten this wrong?" They never raised the idea that Relativity might be wrong. The original paper was very clear and cautious about it.

          What disturbs me is not that the lay media got the wrong message about the OPERA paper, but that the Slashdot writeup got it blatantly wrong. News for nerds, indeed.

      • Of course that was the claim, but in a sane science to layman translation it'd be: "We have this crazy result here with neutrinos that seem to go 60ns faster than light speed.

        Shouldn't be mixing units. 60ns is time, c is velocity. That's like saying you were driving 3 minutes more than 55mph.

        • You never say person A beat person B by 6 cm/s you say person A beat person B by 6 seconds.
          • by Obfuscant ( 592200 ) on Friday March 16, 2012 @04:54PM (#39383659)

            You never say person A beat person B by 6 cm/s you say person A beat person B by 6 seconds.

            That's because the winners of races are based on time, not instantaneous or maximum speed. Drag races always spout speed data, but the winner is the one who crosses the finish line first, not necessarily fastest.

            "60 ns faster than the speed of light" is meaningless. "The neutrinos arrived 60ns sooner than they would have if they were travelling at c" isn't, as long as somewhere you could find out how far they went and then back out the speed they were going.

            • by narcc ( 412956 )

              "60 ns faster than the speed of light" is meaningless. "The neutrinos arrived 60ns sooner than they would have if they were travelling at c" isn't, as long as somewhere you could find out how far they went and then back out the speed they were going.

              Yeah, the rest of us figured that out a long time ago -- you know, because we know how to communicate with each other and interpret what other people are saying.

              Thanks for being needlessly pedantic about it though.

        • by Kjella ( 173770 )

          Shouldn't be mixing units. 60ns is time, c is velocity. That's like saying you were driving 3 minutes more than 55mph.

          Actually in this case it was intended to be a limit, not a velocity. "Usually I drive by the speed limit (55mph) but today I arrived 3 minutes late." is a perfectly reasonable sentence. Of course you can't from this alone say neither distance or velocity, but you can say it went slower than expected which was the essential point.

      • by ediron2 ( 246908 )

        I used to love slashdot because it was common to have (computer, internet and geek hobby) stories done just this way; I keep hoping such a site will arise from the post-slashdot/post-reddit/post-fark/post-twitter ashes. Such a site truly would be 'news for nerds, stuff that matters', as opposed to 'lab breaks speed-of-light' and 'deals another blow' sensationalism even slashdot falls for.

    • First, nobody (except for the press) claimed they saw faster than light neutrinos. You are right on that assumption. Opera basicaly said that they had an interesting result, and couldn't find where it was wrong, now, if anybody out there could help find the problem, they'd be glad.

      Second, Opera found a problem, corrected it, but will only be able to state with certainty that this problem was the cause of the faster than light neutrinos once they run the experiment again. That will take some time.

      Then, what you do when you get such an interesting result is to repeat the experiment. That is what was done here, and the result didn't repeat. That's science working the way it should, and the press working the way we all learned to expect.

      About your question, the neutrinos aren't moving at the speed of light. It is just that their mass is so small that we can't detect the difference between their speed and c.

      • Re: (Score:2, Funny)

        by Anonymous Coward

        Well, if you're going to make the claim that this was "the press working the way we all learned to expect" I would claim that the OP, as an AC ignoring all facts, reading no stories, jumping to a bunch of conclusions based solely on headlines and then using those conclusions to prove to the rest of us that he is the smartest man alive, is "Slashdot working the way we all learned to expect".

      • Re: (Score:1, Funny)

        by SnarfQuest ( 469614 )

        Sorry, bet we have a consensus of the press who have reported that the neutrino travels faster than light. Since this is all that was necessary for Global Warming, it should be good enough for Faster Than Light speeds. Quit denying the facts, and start developing FTL vehicles.

    • by PPH ( 736903 )

      I mean, what kind of a bozo looks at an unexpected result, from an incredibly complex first-one, never-been-done before kind of a machine, and jumps to the conclusion "FASTER THAN LIGHT"!

      That's what it takes to get First Post these days.

    • by jonfr ( 888673 )

      We are to primitive to deal with faster then light. Until we get advance enough, the results are always (in most cases) going to be negative in experiments.

    • what kind of a bozo looks at an unexpected result, from an incredibly complex first-one, never-been-done before kind of a machine, and jumps to the conclusion "FASTER THAN LIGHT"!

      Not the original authors. They published something that can be summarized as "This is probably experimental error but we haven't found a bug in the setup. We're announcing it just in case there is something real here and also to get more eyes to look at the issue and see what the problem might be."

  • "Another blow?" (Score:5, Insightful)

    by Anonymous Coward on Friday March 16, 2012 @02:18PM (#39381415)

    People keep phrasing this like OPERA came out with a headline like "Neutrinos Travel Faster Than Light, and If You Disagree, You're a Stupid Doodyhead."

    That is not what happened. OPERA basically said "Hey, we have this anomalous result that we don't really think could be right, but we looked at all our stuff and couldn't find the problem. Please help us fix this. Thanks."

    • Re:"Another blow?" (Score:5, Insightful)

      by azalin ( 67640 ) on Friday March 16, 2012 @02:21PM (#39381471)

      People keep phrasing this like OPERA came out with a headline like "Neutrinos Travel Faster Than Light, and If You Disagree, You're a Stupid Doodyhead."

      That is not what happened. OPERA basically said "Hey, we have this anomalous result that we don't really think could be right, but we looked at all our stuff and couldn't find the problem. Please help us fix this. Thanks."

      Yeah but that does make a lousy headline, don't you think?

    • Re:"Another blow?" (Score:5, Informative)

      by Sir_Sri ( 199544 ) on Friday March 16, 2012 @02:28PM (#39381575)

      which neatly summarizes the difference between how science is actually done, and how the media, including apparently /. cover science.

      In real science when you do an experiment you just have results. You may not like the result, you may not want that to be the result, and you may think there is something wrong with the results. But that's what you did, that's what happened and if you can't figure out why the results are the way they are, well then you need the broader scientific community to help, and you write it all down in papers so that other people can learn from what happened to you.

    • by guises ( 2423402 )
      Yeah, I'm also confused. The funny measurement that OPERA got has already been explained, there's nothing left to debunk anymore. This is not a blow to anyone's results.
    • Real Science vs. Popular Science (not the magazine)

      The Popular Science treats Science like a religion which teaches "Ultimate Truth" That isn't Science. Science gives us the best/simplest explanation based on what we can observe.

      Now It is possible that we (you) are a Brain in a Box being senses that actually do not exist in the universe, controlled by some higher power, that may be the ultimate truth. However, science doesn't allow this Idea because we cannot observe this effect, and it is a more complicat
    • by chichilalescu ( 1647065 ) on Friday March 16, 2012 @05:12PM (#39383853) Homepage Journal

      somewhere, in a basement, a lonely teenager is writing in his blog: "just like in 1947, the truth got out, but now the coverup begins".

  • by Anonymous Coward
    I like how the submitter has turned it into a war of claims and rival claims. I seem to remember that OPERA was pretty sceptical about its own result right from the start.
  • by Rix ( 54095 ) on Friday March 16, 2012 @02:21PM (#39381465)

    In that experiment.

    Until we know why they were measured as travelling faster than light and can repeat it, the mystery remains.

    • Until we know why they were measured as travelling faster than light and can repeat it, the mystery remains.

      That's not how science works, that's how pseudo-science and conspiracy theories work.

      The burden of proof falls upon the person reporting results out of the ordinary - NOT on those hundreds or thousands of people whose results support the prevailing theory.

      • by Xtifr ( 1323 )

        Until we know why they were measured as travelling faster than light and can repeat it, the mystery remains.

        That's not how science works, that's how pseudo-science and conspiracy theories work.

        No, he's right. The original results are still a mystery. Not a very big one, since they were obtained with faulty equipment, but as I understand it, the discovered faults don't exactly match the necessary cause of the results obtained.

        This isn't a ground-shaking scientific mystery--more like a "why does toast land butter-side down" bit of trivia. But it's something that could be investigated and explained (as the butter-side down [physics.org] question was). Of course, unlike toast, it's likely only of interest to t

    • The current theory is that neutrinos do not travel faster than light.
      This experiment failed to invalidate that theory.
      Therefore, this experiment supports that theory.

      In order for a "mystery" to exist the "faster than light" experiment has to be repeatable.

    • by jfengel ( 409917 )

      We've already got suspicions in that regard as well, including a loose connector cable:

      http://news.sciencemag.org/scienceinsider/2012/02/official-word-on-superluminal-ne.html?ref=hp [sciencemag.org]

      In a perfect world they'd loosen the cable again to see if they can reproduce the same results, but I don't know if they can rustle up the funds for it. Some days, you just recognize that the bug is fixed, commit the code, and go home for the weekend.

  • by Kupfernigk ( 1190345 ) on Friday March 16, 2012 @02:21PM (#39381481)
    OK, perhaps slight trolling, but this is an example of why, on everything from evolution to climate change, I prefer the views of scientists to those of politicians or the religious authorities. This is an example of research happening exactly as it is intended to. Initial unexpected result, investigation, experimental flaw, better experiment. It creates a warm glow in the callous, hardened bit of my brain that was once a young, enthusiastic researcher.
    • Just as a disclaimer: I *do* believe that God created the universe. I also believe that not only does He intervene, but He also holds the universe in existence, and is He intimately aware of everything that goes on.

      I've seen enough evidence, for myself, that I couldn't believe otherwise. I've seen evidence that He actually loves his creation, and is Himself the definition of goodness. Proof? No. Evidence? Yes, though I won't go into it here.

      But I also believe that our science is basically valid while

  • by Biff Stu ( 654099 ) on Friday March 16, 2012 @02:26PM (#39381551)

    299,792,458 m /s. It's not just a good idea. It's the law.

    • by Anonymous Coward

      Well, from what I hear... the only thing faster than the speed of light is the speed of dark--when light reaches an object, the dark was already there.

  • "WHAT ARE YOU LOOKING FOR?" ICARUS later asked, report startled French scientists.
  • by Anonymous Coward

    The new findings are yet another blow to OPERA's results. Researchers there had announced possible timing problems with their original web browser. The latest benchmarks show it has abysmal performance and lacks the scalability and user friendliness of Internet Explorer 9. For many, this will pretty much be case closed.

  • Farnsworth is shouting "WERRNNNSTROMMMM!!!" and shaking his fist in the air
  • ...clocked neutrinos traveling at the speed of light, and no faster, after monitoring a beam of neutrinos sent from CERN in late October and early November of last year

    Sent last year? I would say that puts the speed of neutrinos at considerably slower than the speed of light..

  • "The new findings are yet another blow to OPERA's results. Researchers there had announced possible timing problems with their original measurements." I remember reading after the initial results that they were not sure, but just divulging their findings. Not making a clear cut case that neutrinos did, in fact, go faster than light. They took great pains to open their research and look for alternative answers.
  • Since neutrino's are not affected by gravity, they could still redefine what a straight line is.
    On long distances they could still prove to be faster as they don't curve around gravity fields.
    The sun eclipse experiment done with neutrinos emitted by distant stars instead of photons would be interesting.

    • Everything is affected by gravity that has energy. Although the scientific way to say now is that everything exists and moves in a spacetime that is curved by massive objects (in both meanings).

  • Just went down in flames

  • by PPH ( 736903 ) on Friday March 16, 2012 @03:09PM (#39382141)

    I'm headed over to Usenet right now to tell them top posting is still not OK.

    • What's wrong with top posting???

      I'm headed over to Usenet right now to tell them top posting is still not OK.

      • It can make a discussion hard to read when you only see a single post.

        What's wrong with top posting???

        .

  • How sad that its a big deal that the shuttles are meeting while switching buildings on the ground. If the space program in this country got the proper attention, we'd be making a big deal about two shuttles in space at once meeting with each other.

  • ICARUS is obsolete. After it has merged with DAEDELUS to become HELIOS, neutrinos will be properly calculated to move at super-liminal speeds.
    • by DC2088 ( 2343764 )
      Yeeeessssss.
    • by Xtifr ( 1323 )

      God I hope you're joking! Unfortunately, Poe's Law [wikipedia.org] applies all-too-well here. But whether you meant it to be or not, that was pretty funny, so, if that was your intent, kudos!

      (The actual definition of "liminal" adds to the piquancy of the humor.) :)

  • Einstein is still right, and Karl Marx is still dead. Nothing to see here folks, move along.

  • If they were sent from CERN in October and November and they just got to ICARUS today, isn't that kind of slow? Clearly I am being facetious and obviously IANAS.
  • So did it just occurred to them to look at the data now? ICARUS has weighted in before on this but this is the first time they have a speed measurement, and they are saying it's from the prior runs data. Since the argument was always over the speed of the neutrino and not whether or not the neutrino was emitting the expected radiation if it was going FTL I would have expected them to look at the speed measurement first. We'll at least see in May what the mass of the neutrino really is rather than leaving
  • by Rik Sweeney ( 471717 ) on Friday March 16, 2012 @03:55PM (#39382771) Homepage

    A neutrino walks into a bar, orders a pint, drinks it and leaves without any fuss.

  • Y U NO GO FASTAR THAN LIGHT?!?!?!

    I think they're just lazy, personally.

  • Science. It works.

  • "That meant the timing could be measured far more accurately than the original OPERA measurement, which used ten microsecond pulses."

    To be fair OPERA had access to the same and the results were the same so there is really no point at all in bringing this up unless it is your goal to trick the reader into thinking something about the quality of ICARUS vs OPERA that just aint so.

  • I don't understand. The OPERA experiment blamed on a data link cable seems pretty specious and.. well let's demonstrate that then. In the mean time, how do we measure the passage of time itself? I see that it is not a quantized value; it is the measurement, not a thing to be measured; but it doesn't make sense to me. Events, such as a photon changing position, must occur in discrete intervals, right? How do we know nothing occurs during these intervals? This is a stupid question but I'm very curious for ref
  • Me being chased by a rabid Wolverine.

Avoid strange women and temporary variables.

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