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Neutrino Data Could Spell Trouble For Relativity

Science News has an exploration of the deeper implications of neutrino oscillation, one experimental confirmation of which we discussed last month. "The new findings could even signal a tiny breakdown of Einstein's theory of special relativity. ... MINOS [for Main Injector Neutrino Oscillation Search] found that during a 735-kilometer journey from Fermilab to the Soudan Underground Laboratory in Minnesota, about 37 percent of muon antineutrinos disappeared — presumably morphing into one of the other neutrino types — compared with just 19 percent of muon neutrinos. ... That difference in transformation rates suggests a difference in mass between antineutrinos and neutrinos. ... With the amount of data collected so far, there's just a 5% probability that the two types of particles weigh the same."

25 of 279 comments (clear)

  1. Not trouble... by phantomfive · · Score: 5, Insightful

    This isn't trouble, we already know there are problems with the theory, we just don't have any measurements that give us an idea of how to fix it (of course the theory works well enough in most cases). Any measurements like this that give us something unexpected are great things, they can give us a more accurate picture of how the world is, help the theory become more accurate. Always look for the flaws in your theory, for that is where the greatest discoveries are hidden.

    --
    Qxe4
    1. Re:Not trouble... by jd · · Score: 4, Insightful

      Since every theory is a simplified model, every theory has problems. Sometimes the model works just fine at the resolution and scope for which it is intended (eg: Hooke's Law). It's the cases where you know it's broken within the bounds it should be working for, but you don't know where or why, that are the exciting ones. In the case of relativity, we know it's incompatible with QM at some level that includes gravity but may extend beyond that. We now know that it also has problems with neutrino mass. It may be that relativity can be fixed - at least for neutrinos - but either relativity or QM (or maybe both) =must= break down entirely within their intended scope in a way that is irretrievable. But nobody knows which, when, why or how.

      But this is the fun of science! Science would have no purpose if it weren't for the ferreting out of the glitches and flaws in theories, fixing them and testing them to destruction all over again. We learn so little by being right in comparison to what we learn when we're wrong.

      --
      It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
    2. Re:Not trouble... by Zixaphir · · Score: 5, Insightful

      But this is the fun of science! Science would have no purpose if it weren't for the ferreting out of the glitches and flaws in theories, fixing them and testing them to destruction all over again. We learn so little by being right in comparison to what we learn when we're wrong.

      Wow, if only this applied to programming.

      --
      "Now I am become Death, the destroyer of worlds"
    3. Re:Not trouble... by mangu · · Score: 5, Insightful

      bugs tend to... go over looked, especially in projects that are hobby-based in nature, like many FLOSS programs.

      This happens in commercial software as well. When you buy the next "improved" version they get paid, fixing the current version gives them costs without revenue.

  2. Relativity is just a model by onionman · · Score: 4, Insightful

    It's already widely known that Relativity is just a model... much like the rest of physics. It's extremely accurate and useful for dealing with many areas, but breaks down somewhat when dealing with very very small things. Hence the great desire to develop a more unified theory! So, the summary is a little bit on the sensationalist side of the street.

    The research is very important, though!

    1. Re:Relativity is just a model by onionman · · Score: 4, Insightful

      It's already widely known that Relativity is just a model... much like the rest of physics. It's extremely accurate and useful for dealing with many areas, but breaks down somewhat when dealing with very very small things. Hence the great desire to develop a more unified theory! So, the summary is a little bit on the sensationalist side of the street.

      The research is very important, though!

      That's a gross misunderstanding of the problems of relativity.

      "Just a model" is not what physicists seek. The aim is to seek laws of physics that are absolute, inviolable, and a complete description of space, time, and mass-energy. Some of our models are basically there, like the "conservation" laws, which are based on rigorous mathematics.

      The problem with relativity isn't that it's "just a model", it's that it is explicitly known to be incomplete. It simply doesn't "extend" down to small scales. This was known by Einstein himself, he sought to complete his theory, but failed.

      Sorry, but I'm a mathematician... so everything you physicists do is just a model to me. Ever since I realized (via Goedel) that there aren't even any complete and consistent theories for logic, I sort of figured that there would never be a complete and consistent theory for physics. (Let me know if you find one.) In the mean time, I'm still really impressed with the work physicists do! I really should finish working through Gravitation some day... that's cool stuff.

    2. Re:Relativity is just a model by Anonymous Coward · · Score: 5, Funny

      Sorry, but I'm a mathematician... so everything you physicists do is just a model to me.

      An instant link to xkcd is required here. I hate doing this (linking to xkcd), but you brought it on yourself :)

  3. So basically... by Anonymous Coward · · Score: 5, Funny

    Let me try to find a lay-person analogy.

    A chef theorized that there was a counter-part to bacon. We'll call it turkey bacon. We traditionally thought that Turkey Bacon was the direct opposite of Pig Bacon. Where Pig Bacon was delicious, Turkey Bacon was healthy. We decided to do some research on how Turkey bacon and pig bacon is received by the consumer. Recent taste test show that turkey bacon is not, in fact equally as healthy as pig bacon is tasty. This ruins the grand unified theorem of HTB (healthy tasty breakfast).

    The only remaining explanation is there might, in fact, be a third type of bacon... i.e. a cow bacon or chicken bacon. If we discover this new type of bacon, it might completely revolutionize the Bacon Lettuce Tomato sandwich.

    amirite?

    1. Re:So basically... by Hognoxious · · Score: 5, Funny

      The car analogy works as a reasonble approximation at vehicular scales but breaks down at the edible level.

      --
      Confucius say, "Find worm in apple - bad. Find half a worm - worse."
    2. Re:So basically... by Linker3000 · · Score: 4, Funny

      I'm waiting for the Higgs Bacon.

      --
      AT&ROFLMAO
  4. How does this violate special relativity? by JoshuaZ · · Score: 4, Insightful

    Ok. I read the article and I'm still confused. I understand why different mass for particles and their antiparticles would violate CPT, which is obviously major. But I don't see how this violates special relativity. Why does this violate special relativity?

  5. There is already trouble by fermion · · Score: 5, Interesting
    Here are three things I see to be a consistent form of trouble. First, obviously as we exist, there was not an equal amount of matter and anti-matter created at the big bang. Furthermore most kludges that have been devised to explain this discrepancy have been less that stellar and have tended not to match real data very well, unless they have been tweaked to arbitrarily match real data.

    Second, we think there are infinities in the universe, and infinities tend to be catastrophic in the real world. In fact, classical mechanics met it's catastrophe in an infinity. It is unlikely that all the infinities that are created between quantum mechanics at the atomic scale and relativity at the universal scale can simply be normalized out, and black holes are not going anywhere until general relativity is fixed.

    Then of course we havethe hacked dark matter née aether to make everything work out and match the theory. In light of these three things, any new data, especially new data the violates current theories, are not problem buy jewels. Jewels that will help us refine, and supposed depose, old theories. It is why we still train scientists, and laught at those that think the world is so boring that there is nothing left to be discovered. Fortunately for those that are curious, nature has new surprises every day. I would hate to live in a world where the special theory of relativity was gospel. Such a world would so boring that I would probably be thinking not of what wonders will come, but how life can be ended.

    Especially since I squandered my youth solving those god forsaken equations.

    --
    "She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
  6. So... by fuzzyfuzzyfungus · · Score: 5, Funny

    Should I be preparing for Unforeseen Consequences?

  7. CPT = Lorentz Invariance by SciBrad · · Score: 5, Informative

    If I recall correctly CPT presumes the correctness of Lorentz invariance. And Lorentz invariance is one of the bedrocks of relativity. In other words CPT comes about from assuming your theory is Lorentz invariant and if CPT were violated it would mean Lorentz invariance is violated as well (check out Physical Review Letters 89: 231602 by Greenberg, O.W, which shows CPT violation implies Lorentz violation).

    1. Re:CPT = Lorentz Invariance by JSBiff · · Score: 5, Funny

      Well, you see, the modder had to preserve Slashdot CRM ( Correctness, Relevance, Modding) Invariance which states that Comment Correctness, Comment Relevance, and Comment Modding, when assigned a boolean value (e.g if the Comment is factually correct, it is assigned the value of 1, else 0) of 1 or 0, then multiplied together, must never be 1. So, since we had a correct, relevant comment, the modding must be incorrect to preserve the Invariance.

    2. Re:CPT = Lorentz Invariance by JoshuaZ · · Score: 4, Informative

      It's a lot easier than tossing out your beloved theory or trying to build it up from scratch based on solid scientific evidence to support each individual tenet. I think the latter is what needs to be done, but it will take time. We need to re-figure out what we know absolutely. IOW, what aspects of special relativity are not contradicted by a CPT violation? If the Lorentz Transformation is called into question then so is science fiction's much beloved time dilation And what about the Twins Paradox? Yikes.

      Time dilation has been observed in a number of different contexts, most famously by putting atomic clocks on airplanes and measuring the resulting slow down as they fly around the globe. Even if SR fails, time dilation is still an experimentally verified fact.

    3. Re:CPT = Lorentz Invariance by TapeCutter · · Score: 4, Informative

      "Time dilation has been observed in a number of different contexts"

      Indeed! Without taking time dialation into account GPS locations would systematically drift about 10km/day.

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
  8. Newton's laws would be a great example by Sycraft-fu · · Score: 5, Insightful

    They are wrong on a universal scale. This has been proven, and indeed it is where things like relativity start to come in. We have measured things that go against the predictions that Newton's laws make. That would mean they've been falsified. ...

    So why the hell do we still teach them?

    Well because on the scale we normally work on, Newton's laws simply and accurately describe how things works. You can go out yourself and test them in any number of ways and you'll find that as accurate as you want to measure, they are dead on accurate. When dealing with the scale of things humans normally do, they are an excellent set of rules for calculations.

    Thus more accurately put they aren't wrong, they are just a simplification that works within certain bounds. They do not fully describe motion and gravitation on every level, in every case. They break down for very large and very small scales. However they are an excellent simplification for anything less than, say, a planet in size and anything above the atomic level. That would include basically everything you are ever likely to work with.

    So they are very much correct, all you have to do is put a couple constraints on their use.

    Simplified models like that are wonderful too. Even if they don't explain everything, they allow for calculations to be done in an easy fashion on things we care about. Some day we may discover a truly complete law for motion, that covers all cases from the smallest to the largest. at all speeds, in all frames of reference and so on. There may be nothing left out. It also may be several pages of dense calculations. Instead of that, when dealing with a normal, human scale, we'll still use Newton's laws, something you can express in a couple characters and work out in your head if you are good. An exceedingly useful and accurate simplification.

    A similar example would be the Ideal Gas law. When you look at it, it is clearly wrong. Reason is you plug in numbers for something like H2O at room temperature and the result is not what you actually get. It does not show it becoming a liquid. Yet again we use it. Why? Because so long as the substance you are talking about is a gas in the temperature and pressure range you are working at, the Ideal Gas law gives you a very easy, highly accurate, way to calculate things about it. It is a simplification, hence why it is called "Ideal Gas" instead of "Real Gas". That doesn't mean that it isn't accurate and useful within some constraints.

    So I can see the same being true with relativity. While we have already found cases it doesn't explain (see quantum gravitation), that doesn't mean it isn't useful within certain constraints. As our knowledge progresses, we will know precisely what those are.

    1. Re:Newton's laws would be a great example by JSBiff · · Score: 4, Interesting

      I wish I could find the URL now, but I remember reading once about relativity (don't remember now if it was special or general), the author showing how some of the classical mechanics formulas are basically the first few terms of Taylor Polynomials which represented the values given by relativity, so basically, as you said, they are accurate when sufficiently near 0, but the farther you move away from 0, the more the error accumulates without the 'missing' terms. Really wish I could find it now.

    2. Re:Newton's laws would be a great example by IICV · · Score: 5, Interesting

      Actually! I was looking this up at one point for some reason I forget, but:

      You cannot explain the yellowish color of gold* without relativity. If you just use classical chemistry, it should be silvery-white, just like silver. It's also the reason why mercury is one of two elements that are liquid at room temperature; relativistic forces screw with the electrons, making them bind more weakly. Although the reasons why these things happen do come from a level outside of your bounds (it has to do with electrons, which are smaller than atoms) the effects are things everyone takes for granted.

      Gold would not be golden if it weren't for relativity! I just find that so amazing.

      *It's also how you explain the yellowish color of cesium, but that's not something most people are familiar with.

  9. CPT Symmetry by DrJimbo · · Score: 4, Informative
    The fine article said:

    If the interactions of particles are thought of as a movie, CPT symmetry requires that whatever physics occurs during the show must be the same whether the film is run forward or backward (time), viewed through a mirror (parity) and repopulated with each particle being replaced by an antiparticle (charge).

    This is unclear at best. CPT symmetry says that when the film is run backward AND seen through a mirror AND all particles are replaced with the anti-particles (and vice versa) then the physics should be the same.

    If you change just one, for example by running the film backward but without the mirror or the the particle exchange, or if you change two, for example, running the film backward and with the mirror but no particle exchange, then the physics will change.

    --
    We don't see the world as it is, we see it as we are.
    -- Anais Nin
  10. Cloaking device malfunction?! by SOOPRcow · · Score: 5, Funny

    I think we need to reroute power through the main deflector dish to correctly mask the neutrino particle dispersion.

  11. Found a source by JSBiff · · Score: 5, Interesting

    Found a pdf of calculus notes on northwestern.edu which shows what I was talking about.

  12. Re:statistics fail by Parlyne · · Score: 4, Informative

    The correct statistical statement here would be that an experiment like this one would show a splitting between particle and anti-particle properties at least this large 5% of the time even if there were no difference at all.

  13. Re:I think I had an astronomy prof that talked abo by ultranova · · Score: 4, Informative

    That a theory is just a tool for understanding and predicting reality.

    But a theory is more than just that, it's a mental model of reality, the context for sensory input. Einstein's General Relativity and Newton's Laws of Motion are fundamentally different: Newton took time and space to be a passive background, while Einstein made spacetime an active participant in events. The two theories don't just differ a little bit on their results, they represent fundamentally different ways of looking at reality.

    But in a way your professor was right: a theory is "just a" tool for understanding reality, in the same way as you brains "just" allow you to think.

    --

    Forget magic. Any technology distinguishable from divine power is insufficiently advanced.