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Chameleon-Like Behavior of Neutrino Confirmed 191

Posted by Soulskill
from the yes,-neutrinos-eat-bugs dept.
Anonymous Apcoheur writes "Scientists from CERN and INFN of the OPERA Collaboration have announced the first direct observation of a muon neutrino turning into a tau neutrino. 'The OPERA result follows seven years of preparation and over three years of beam provided by CERN. During that time, billions of billions of muon-neutrinos have been sent from CERN to Gran Sasso, taking just 2.4 milliseconds to make the trip. The rarity of neutrino oscillation, coupled with the fact that neutrinos interact very weakly with matter, makes this kind of experiment extremely subtle to conduct. ... While closing a chapter on understanding the nature of neutrinos, the observation of neutrino oscillations is strong evidence for new physics. The Standard Model of fundamental particles posits no mass for the neutrino. For them to be able to oscillate, however, they must have mass.'"
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Chameleon-Like Behavior of Neutrino Confirmed

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  • No. (Score:1, Insightful)

    by gbutler69 (910166) on Monday May 31, 2010 @05:57PM (#32411460) Homepage

    Something PROVED TO BE missing from the Standard Model? Shocking!^H^H^H^H^H^H^H^H INTERESTING

    There, fixed that for you

  • Excited! (Score:5, Insightful)

    by SpeedyDX (1014595) <speedyphoenixNO@SPAMgmail.com> on Monday May 31, 2010 @05:57PM (#32411462)

    Reading TFS made me very excited about the potential fundamental developments in physics. Except I don't know a thing about physics, so I'm really not sure what I'm excited about. All these words like muon, tau, and neutrino have little place in my everyday life, but they sound so interesting!

    This is what the Average American must feel like when they hear stories about Web x.0 laden with the latest buzzwords on CNN. I can finally relate!

  • Re:What if... (Score:5, Insightful)

    by BitterOak (537666) on Monday May 31, 2010 @06:31PM (#32411828)
    That would be pretty amazing as it would violate the Special Theory of Relativity, one of the most tested theories of all time. The problem is, according to Special Relativity, massless particles move at the speed of light, and time does not advance for them. (If you could build a massless clock, its hands would never move.) Oscillations require a time scale. There is a time period of oscillation, or rather the probabilities of being found in a specific state (mu vs. tau, for instance) oscillate with time. Since time stands still for massless particles, this can't happen.
  • Re:Excited! (Score:5, Insightful)

    by biryokumaru (822262) <biryokumaru@gmail.com> on Monday May 31, 2010 @06:51PM (#32412006)

    Imagine your definition of sports cars (massless particles, thus no time) didn't include convertibles (time-based oscillation). For a car to be convertible, it has to be a luxury car (have mass), not a sports car. Then, you see a sports car drive by a few times, and one of the times the top is down. You have to wonder, is it not really a sports car (the way we think neutrinos work must change), or is your definition of sports cars broken (the way we think mass works must change)?

    How's that sound?

  • by oldhack (1037484) on Monday May 31, 2010 @07:43PM (#32412396)

    We've been observing only a third of neutrinos from the sun, and the speculation was that the rest were oscilliating into others not being detected, and that would be possible if neutrinos had mass, and that means one or the other symmetries in the standard model needs to be tweaked, and so on.

    Get it? No, I don't get it either, but I'm no physicists.

  • by syousef (465911) on Monday May 31, 2010 @07:51PM (#32412446) Journal

    If two theories explain the same data equally well, the simplest is more likely.

    Is that really the case? That seems like it's a very hominid-centric assumption. I can't think of any counter examples but it seems very naïve to assume that the nature of the Universe would be simple...? Though, perhaps my understanding is limited.

    Well it's VERY difficult to detect relativistic effects at human walking speed but they are still there. So you could create a whole stack of data that supports Newtonian physics over Relativity on that basis, but Relativity, though more complex is a more accurate description of the Universe.

    When something doesn't fit your model, more experimentation and experience is needed, and most importantly you may need to do DIFFERENT experiments to determine whether a simpler or more complex theory is more accurate.

  • Re:What if... (Score:5, Insightful)

    by Steve Max (1235710) on Monday May 31, 2010 @08:14PM (#32412628) Journal

    The point is that, if two different theories have the exact same predictions, they are for all intents and purposes the same theory, and describe the same universe. If that is the case, why would you spend more time teaching and learning the more complex one, when a simple explanation is enough and (by definition, since they have the same predictions) you can't tell which one is correct?

    Of course, if the new theory offers a good explanation to current data, but has a different prediction than the standard model in other, still-non-tested scenarios, the theory is more interesting. You can test it at the new scenario, and you'll be able to tell them apart. This is why* we study, for example, supersymmetry and extra dimensions theories: they behave just like the standard model where we have tested it, but can be different in other cases such as the LHC.

    * = of course there are other motivations to develop the theories, but they are taken seriously because they are compatible with the SM and are testable. A theory whose predictions were exactly the same as the SM for every case wouldn't be worth studying, simply because you'd never be able to see if it is right.

  • Re:What if... (Score:5, Insightful)

    by Hurricane78 (562437) <deleted.slashdot@org> on Monday May 31, 2010 @08:28PM (#32412734)

    No it is not more likely. That’s a common misconception. It is only the one you should pursuit first. Actual facts make things more likely. Not simplicity. Simplification is a artifact injected by humans, because they prefer it for efficiency. (What is commonly calley “laziness”)

  • Robust result? (Score:3, Insightful)

    by harryjohnston (1118069) <harry.maurice.johnston@gmail.com> on Monday May 31, 2010 @10:02PM (#32413454) Homepage

    Offhand, this doesn't seem like a very robust result - we're only talking about a single observation, after all. Does the equipment allow them to determine the source of the observed tau neutrino? How can they be sure that it came from the muon neutrino stream from CERN rather than being random background?

    There's also no mention of a control, e.g., another tau neutrino detector close to the same muon neutrino source. Even if there was, is a single detection versus no detections statistically significant?

  • by SigNick (670060) on Tuesday June 01, 2010 @05:22AM (#32416070)

    1. If an electron neutrino can spontaneously transform to a tau neutrino with higher mass, where exactly does the required energy come from? Alternatively, when a tau neutrino transforms to an electron neutrino, where does the extra energy disappear?

    2. If neutrinos have mass, then they are restricted to speeds below c. If they are accelerated to near c, then according to the relativistic energy-momentum equations they should have colossal mass, not miniscule (just like electrons, for example). Is there any evidence of observing neutrinos with huge energies?

    The Wiki article about neutrino oscillation paints the picture that the oscillation is a pseudo-illusionary quantum mechanical effect, and therefore questions like the two above are meaningless. Smells more like handwavium to me.

    Could a real physicist push back the veil of shadows one bit? Pretty please? =)

  • Re:Excited! (Score:5, Insightful)

    by rumith (983060) on Tuesday June 01, 2010 @07:21AM (#32416606)
    'Tis one of the best comments I've ever come across on Slashdot :)
  • by ProteusQ (665382) <dontbother@@@nowhere...com> on Tuesday June 01, 2010 @01:22PM (#32420656) Journal

    This reminds me of the /. post a few days ago about those who are ignorant of science and proud to be so. This is how I think some of them might perceive this situation:

    Last week, a Normal would have been told by Those Who Do Science that a neutrino has no mass, and that is the end of the matter. A non-physicist has nothing to contribute to the discussion. Persistent disagreement amounts to sheer ignorance, so keep quiet.

    But now, it would appear that either neutrinos have mass or the Standard Model is wrong. Science has revealed its own ignorance. Everyone who was wrong last week is right this week. But the message to the Normals remains the same: it doesn't matter that we were wrong last week; eventually, We Who Do Science get it right. You still have nothing to say. Keep quiet.

    The Normals perceive the above and conclude that it's hypocrisy. Hence, they can ignore science and be proud that they are smart enough to avoid hypocritical know-it-all's.

    BTW: Yes, this is post if Offtopic, but it's not Flamebait or Troll. I'm not agreeing with this POV; I'm passing on my perception of it. And how else can one discuss the interrelationship between topics without being regarded as Offtopic in regards to one post or the another?

    I wish I had an answer of how to fix the above problem. Eliminating arrogant PhD's would be helpful, but that would leave all of the arrogant Normals -- and the rest of us aren't free from shocking amounts of arrogance at times, either. We could use another Sagan to highlight that math+science is a process that anyone can join in on once the ground-rules are mastered. However, it would me imperative that the next spokesperson not be hostile to religion -- the Normals are hypersensitive to this issue, and getting in their face about the matter only increases the alienation. [Not saying that Sagan was hostile to religion -- just saying then next spokesperson cannot be.]

To err is human -- to blame it on a computer is even more so.

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