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Science

Neutrinos, Muons and the Standard Model 230

Posted by michael from the lions-and-tigers-and-neutrinos-oh-my dept.
scorp1us writes: "I can't believe I haven't seen this posted yet. Apparently experiments in particle physics aren't holding to theory. The result: a search for a new form of energy or matter. Read about it in the Post. No wonder witches weigh as much as a duck."
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Neutrinos, Muons and the Standard Model More

Neutrinos, Muons and the Standard Model

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  • Your logic escapes me. (Score:3, Funny)

    by Keith Mickunas ( 460655 ) on Friday November 09, 2001 @04:53PM (#2546028) Homepage
    Witches weigh as much as a duck because they're both made out of wood. Everybody knows that.

  • A "high" powered "particle" beam? (Score:5, Funny)

    by Anonymous Coward on Friday November 09, 2001 @04:54PM (#2546036)
    Peter Meyers, a professor of physics at Princeton University who was not part of the research team, said the finding is the "sort of crack" that "has been sought for many, many years."

    Great. It looks like it's not just the moderators, then.
  • bu they have restricted access since 09/11. You can't even hike in the woods around it anymore.

  • Um...yeah? (Score:4, Informative)

    by BMazurek ( 137285 ) on Friday November 09, 2001 @04:55PM (#2546043)
    I can't believe I haven't seen this posted yet.

    I think it was posted yesterday [slashdot.org]. It just didn't reach the front page.

    That article had many more references, too...

    • Re:Um...yeah? (Score:2, Insightful)

      by Random Walk ( 252043 )
      And the funny thing is that the worse article has attracted already about six times as much posters ... seems the newspapers are right in dumbing down stories to the least common denominator.

      Apart from that, it is an interesting result, but only three sigma from the standard model, which is not really too much if you want to announce something groundbreaking. Sometimes even four sigma results turn out to be just experimental outliers.

      • Re:Um...yeah? (Score:2, Informative)

        by Debillitatus ( 532722 )
        And the funny thing is that the worse article has attracted already about six times as much posters ... seems the newspapers are right in dumbing down stories to the least common denominator.

        I think it might have something to do with the fact that it landed on everyone's front page, eh?

        Apart from that, it is an interesting result, but only three sigma from the standard model, which is not really too much if you want to announce something groundbreaking. Sometimes even four sigma results turn out to be just experimental outliers.

        Yeah, I'd have to agree with that. Three standard deviations is worth noticing, but it's not worth getting all crazed out. After a few more runs, we'll see what's up.

  • I had always wondered about all the hard "facts" in science. Considering that most of science is based on educated guesses, it was only a matter of time before real hard facts started surfacing. Maybe this is the start of disproving Einstein's theory.

    • Re:Always wondered... (Score:5, Interesting)

      by Daniel Dvorkin ( 106857 ) on Friday November 09, 2001 @05:12PM (#2546123) Homepage Journal
      All science is based on "educated guesses." It's just that some guesses are much more educated than others, and turn out to fit the facts pretty well. Relativity is one of those very good guesses, along with Newton's laws (and no, Einstein didn't replace Newton, just refined Newtonian physics in a small but significant way), Darwinian evolution, plate tectonics, Boyle's law, etc. ...

      But this is the defining characteristic of science: everything, always, is open to question. Hypotheses that are borne out by experiment and observation turn into theories, and those theories which stand the test of time are honored by being called laws, but none of them are "facts" in the sense that they can't be proven wrong. This is the principle of falsifiability, and it is the one thing which sets science apart from religion, philosophy, law, and other areas of human intellectual endeavor which seek to make statements about our world.

      So relativity isn't a "hard fact." Neither is gravity. But that gravity, and relativity, and evolution, and plate tectonics, et bloody cetera, will operate the way the theories say they will, is the way to bet unless and until something dramatically better -- and by "better" I mean "backed by lots of reproducible evidence" -- comes along.
      • I think the principle of falsifiability has gone out of vogue almost entirely. Karl Popper, who popularized the principle of falsifiability, shifted to a weaker form of the principle in his own lifetime, and post-modern critiques of the principle have eroded its popularity greatly.

        The main critique against the principle is that scientific propositions require auxilliary hypotheses to have any predictive value. When a specific prediction is falsified, it is possible to "get around" the problem by modifying the auxilliary hypotheses. Since such modification to auxilliary hypotheses is considered a normal part of the scientific process, falsifiability doesn't really work very well.

        Or something like that... it's been a couple of years since I studied this stuff.
        • Could you give some examples of what you're talking about? For the record, I work in biotech, and pretty much our whole business is built on falsifiability; I've never heard a working scientist argue seriously against it.

          • Re:Always wondered... (Score:4, Informative)

            by MarkusQ ( 450076 ) on Friday November 09, 2001 @07:18PM (#2546798) Journal
            ...the principle of falsifiability has gone out of vogue...Karl Popper...shifted to a weaker form...post-modern critiques...have eroded its popularity greatly...scientific propositions require auxilliary hypotheses to have any predictive value. When a specific prediction is falsified, it is possible to "get around" the problem by modifying the auxilliary hypotheses. Since such modification to auxilliary hypotheses is considered a normal part of the scientific process, falsifiability doesn't really work very well.

            ----------

            Could you give some examples of what you're talking about? For the record, I work in biotech, and pretty much our whole business is built on falsifiability; I've never heard a working scientist argue seriously against it.

            ----------

            I'll take a stab. Suppose I say "It's raining outside." This sounds like a classicly falsifiable statement. But is it? If you look out the window and don't see rain, it may be that I was wrong. Or (I could perversely argue) it could be that you (incorrectly) assumed that

            1) by "outside" I meant "outside, near this building" not "outside, somewhere"

            2) the rain would be all around, not just on the side of the building with the window

            3) the rain drops would be large enough to see

            4) there would be enough rain drops to notice

            5) it would still be raining by the time you looked

            6) enough photons would interact with enough raindrops before reaching your eyes that you would detect the rain (instead of all missing)

            7) the window really is a window, and not a clever high-res display

            ...and so on and so forth. The point is there are an infinite number of these silly secondary assumptions needed to go from "it's raining outside" to "if I look out that window I should see rain"; failure of the second claim does not falsify the first.

            The hard core rationalist claim that "all it takes is a single counter example to disprove a theory" doesn't really work. In practice, then, we deal with a sort of fuzzy-falsification, and come up with estimates (w. specified confidence levels) that an assertion is true or false. A single test can't really topple a theory since you can't know for sure that the problem was in the theory and not in your test.

            Make sense?

            -- MarkusQ

            • Strawman Argument (Score:2, Informative)

              by forii ( 49445 )
              I'll take a stab. Suppose I say "It's raining outside." This sounds like a classicly falsifiable statement. But is it? If you look out the window and don't see rain, it may be that I was wrong. Or (I could perversely argue) it could be that you (incorrectly) assumed that
              [deleted various arguments]

              All this goes to show is that your "classicly falsifiable statement" is a bad theory. This is why actual theories are either much more complicated, taking into account all sorts of possibilities (as you detailed), or are very explicit (as in the F=ma form).

              Making a statement, in casual language, as you did, is not thorough enough. For example, one could say "Nothing can go faster than the speed of light.", but that isn't the actual theory. In fact, the theory is just a set of mathematical equations that show (among other things) that the mass of an object increases by a factor of (1/sqrt(c^2-velocity^2)), so that unless something can have an infinite mass (or a resting mass of 0), it can't go at the speed of light. And other fun things that all, together, show that nothing can travel at the speed of light.

              A single test can't really topple a theory since you can't know for sure that the problem was in the theory and not in your test.

              Sure, testing errors are always possible, but this is what repeatability is all about. A single test , run multiple times, can definitely topple a theory. If two separate people do the exact same test and come up with the same disagreement with the theory, then the chances of testing error are much smaller. The point is that if a theory can't explain a discrepancy, then the theory is either wrong or incomplete.
            • Well, yeah, it makes sense, but frankly, to me it sounds like the argument of a philosopher who doesn't really understand how good science operates. Any well-designed experiment or well-written report of observations will list the assumptions involved.
              • Sorry, that's an almost true. Like nearly everything else.

                A good report of a well designed experiment will list all of the assumptions that the experimenters thought of and considered important. It won't list the things that were considered too obvious. It won't list the effects that were considered too small. etc.

                The real world may not be infinitely complex, but it is more complex and interactive than any intelligible procedure can handle. The trick is to find cases that are simple enough to be understood. That means where, e.g., you can ignore the friction when comparing the time for two balls to drop (a Galileo and his trough reference).

                No, you can't simply depend on falsifiability. You also need to use Occam's razor. And it is known to be undependable. So you need to come up with several different approaches to the same point.

                Falsifiability is a crude description of the real process. But it was simplified to cause it to be intelligible. And it is a necessary component. Not sufficient, but necessary. Even though, because of it's dependancy on Williams untrustworthy razor, you can never reach certainty. Ever.
          • I guess my point wasn't that a theory that is clearly unfalsifiable can be scientific, but rather that the criterion of falsifiability isn't a good test for how scientific a theory is. Any theory can be protected from falsification by the introduction of ad-hoc hypotheses, but just because a theory contains ad-hoc hypotheses doesn't make it unscientific.

            Let's take for example the criticism of Lakatos. When the perturbation of the orbit of Uranus was conclusively demonstrated, one might have said that the Newtonian theory of gravity had been falsified. To wit, an auxilliary hypothesis was introduced: "perhaps there is another, unseen, body causing the perturbation". In this particular case, the offending body (Neptune) was discovered shortly thereafter. But what if, for some reason, Neptune continued to evade terrestrial observation? Would that invalidate the entire Newtonian program? Not at all, it would merely have remained an ad-hoc ancilliary hypothesis.

            Obviously, when a theory becomes too full of such ad-hoc hypotheses we become doubtful of its viability as a working scientific model. And rightly so -- the Copernican model of the cosmos replaced the Ptolemaic model for exactly this reason. But does that mean that the Ptoemaic model was unscientific?
      • The interesting thing to think about in all of this is that the goal of science is to find the "real" and underlying "truth". Obviously we are still a little way out from this "holy grail" however I would venture to say we have made considerable progress. Somehow, somewhere out there the truth does exist however, and we simply have to find it and realize it. Some would argue that there is no real truth since the universe is inherently chaotic and is constantly reinventing itself. If this were the case then the everyday ordinary things we take for granted (such as the earth revolving around the sun) could just all of a sudden change. Of course our evidence points otherwise, so we can probably safely assume that the "truth" does actually "exist". Now we just need to find it. You are correct in the saying science is a bunch of theories, because in fact until we hit upon the full truth we only have guesses, hypothesis and "partial truths" that may explain one phenomena or another. That is what makes science, particularily physics, so interesting it is a constant quest for "truth" which will never really end until we reach the omega point.
    • Can't remember where I heard it, but there is a story about a Physics exam...

      A group of tourists is being taken around the Physics department of a major university, and one tourist is puzzled by a long document mounted in a glass case in the foyer that they pass on the way in. When the tour ends in the same foyer, he asks the guide about the document.

      ``That's our exam,'' he is told.

      Stunned, he asks, ``What? Don't you change the questions every year? Don't people just read it and cheat?''

      ``Well, no...'' the guide responds, ``we have a much better system. We only change the answers.''
  • Maybe I'll win that bet I made with my highschool physics professor that I could break at least one before I die! :)

    Seriously though, this is cool stuff, I'd read the actual paper when it gets published but I'm sure I'd drown in a see of evil mathematics.

  • Changing theories (Score:4, Insightful)

    by Debillitatus ( 532722 ) <devillel2@hotmaP ... minus physicist> on Friday November 09, 2001 @04:58PM (#2546069) Journal
    I can't believe I haven't seen this posted yet. Apparently experiments in particle physics aren't holding to theory

    I think that this is maybe not so surprising. Theories in particle physics are very unlike a lot of other theories. There's not much evidence sitting around for some of these things, and as new evidence comes in, the theories change.

    This is true for any scientific endeavor, but the changes are much more rapid in things like high-energy physics.

    In short, I'm just saying that it shouldn't be taken as a "radical breakthrough" just because someone had the muon equation wrong, because it was going to happen at some point.

  • prompting physicists yesterday to announce that they might be on the verge of finding a new form of matter or energy.

    I thought the guys who won the Nobel Prize for Physics already discovered a new form of matter. Is this more of their findings, or something totally different? Does this mean that there could be 2 new forms of matter to bring the total up to 5 forms?


    Plus:

    "On a statistical basis, that would be a 1 in 400 probability of happening as a result of chance. "

    That doesn't seem like a big deal to me. That sounds more like a problem in the experiement. I don't think anyone should be jumping for joy at this discovery until they duplicate it in another test.

    • Follow-up experiments. (Score:4, Informative)

      by Christopher Thomas ( 11717 ) on Friday November 09, 2001 @05:11PM (#2546121)
      "On a statistical basis, that would be a 1 in 400 probability of happening as a result of chance. "

      That doesn't seem like a big deal to me. That sounds more like a problem in the experiement. I don't think anyone should be jumping for joy at this discovery until they duplicate it in another test.

      This *is* a duplicate experiment - or close to it. Check the previous Slashdot article on the subject. This project is measuring a value that was measured by three previous experiments. Two of the previous experiments gave a very wide range for results, and the other one gave a narrow range for the results consistent with this experiment's results.

    • Re:More forms of matter? (Score:5, Informative)

      by Mr. Slippery ( 47854 ) <tms&infamous,net> on Friday November 09, 2001 @05:27PM (#2546193) Homepage
      I thought the guys who won the Nobel Prize for Physics already discovered a new form of matter. Is this more of their findings, or something totally different?

      Totally different. The Nobel guys found a new state of matter, the Bose-Einstein condensate.

      Does this mean that there could be 2 new forms of matter to bring the total up to 5 forms?

      There's already (at least) 5 states of matter: solid, gas, liquid, plasma (gas so hot that it gets ionized - the sun's made out of it), and the recently confirmed Bose-Einstein Condensate [colorado.edu] (gas so cold that weird quantum things start to happen).

      You've also got the degenerate states of matter found in white dwarfs (where the electrons squeeze together), neutron stars (where the electrons smush into the nucleus), and black holes (where...well, it all breaks down there). These don't seem to be counted in the usual enumeration of states of matter, but then they've never been produced on Earth, they're really still theoretical.

      What they'd be looking for out of this new discovery is more along the lines of a new fundamental particle or force.

      • Excellent explanation of the BEC! Thanks Mr. Slippery!
      • There's already (at least) 5 states of matter: solid, gas, liquid, plasma (gas so hot that it gets ionized - the sun's made out of it), and the recently confirmed Bose-Einstein Condensate [colorado.edu] (gas so cold that weird quantum things start to happen).

        There are also higher temperature states above plasma. A plasma is a gas that's so hot the kinetic energy of the atoms is larger than the binding energy of the electrons and they get stripped.

        If you raise the temperature more (a lot more) above the binding energy of nucleons in the nucleus, all nuclei break down and you have a gas of just protons and electrons.

        Beyond that, there might be a state where the nucleons themselves break apart into a "quark-gluon plasma". This hasn't been experimentally discovered yet, but it's what they're looking for at RHIC [bnl.gov].
    • I was under the impression there were already 5 forms..
      solid, liquid, gas, plasma, bose-einstein condensate?
      • I hate to pick nits, but here I go:

        These are five 'states' of matter, each one obtained (at least for the first four you list), by adding more and more energy into the system. I am not very familiar with bose-einstein condensates, but I believe (someone please correct me if I am wrong) they are a state of matter that occurs at energies close to absolute zero, and are thus just another step on the continuum with which most of us are familiar.

        I think that examples of different 'forms' (to which they are referring in the article) of matter might be regular matter and antimatter, but don't quote me on that.

  • Deja vu, and not a very good article. (Score:5, Insightful)

    by Christopher Thomas ( 11717 ) on Friday November 09, 2001 @05:00PM (#2546080)
    This was posted a few days ago, along with links to much better articles:

    http://slashdot.org/article.pl?sid=01/11/08/222121 3 [slashdot.org]

    What the experiment shows is that the plan-vanilla Standard Model doesn't perfectly match reality. This is a surprise to nobody.

    The results give a tantalizing look at one region of this breakdown, but proclaiming "a new form of energy or matter" is a bit premature at this point. What this will actually do is help confirm, refute, or fine-tune a few of the new models that are replacement candidates for the Standard Model.
    • From the article it might seem that we the Standard Model (SM) has been checked for 20, 30 years and this would be the first time to find something that is not predicted correctly. That is not the case:
      • In June we got the news [slashdot.org] from the Sudbury Neutrino Oscilloscope [queensu.ca] that from the detection rates of muon-type and electron-type neutrino's coming from the Sun we should conclude that neutrinos oscillate (change type) and are therefore massive, which is in full contradiction with the SM.
      • In March this year the results of the 1999 data of the muon g-2 [uiuc.edu] measurement at Brookhaven National Laboratory showed [arxiv.org] that the (anomalous) magnetic moment of the muon is not described correctly by the SM. This 'magnetic moment' indicates how much the spin of a muon is affected by a magnetic field (a bit like how quickly a compass needle reacts to a new orientation of the compass). This measurement generated lots [bnl.gov] of theoretical ideas for mods of the SM and/or signs of supersymmetry and what not.
      • The Standard Model is ugly.
      And I am now probably also failing to mention other important failures of the SM.

  • Not Reviewed Yet (Score:5, Informative)

    by TheBoquaz ( 530526 ) on Friday November 09, 2001 @05:00PM (#2546083) Homepage
    I found it interesting that these "results" ended up in the media before being accepted by the Journal they are publishing in.

    In science, especially physics, there is a tradition of review which has caught many claims such as this before.

    It is likely that they have missed some minor force or effect in thier Standard Model calculations, or that we simply need to understand neutrinos better.

    Until a Physical Review Journal accepts research, and even sometimes after that, it should not be viewed as anything more than fantasy.
    • yeah, can anyone say cold fusion...
      • I don't remember the details, but there apparently have been some recent experiments with cold fusion that have produced results that could possibly be explained by cold fusion. It's all preliminary, AFAIK.
    • That's fine. If you areconfident in y our results and your results are sufficiently groudbreaking that itdeserves to be told to Joe Public who funds it in the first plac.

      You can get the articles (not-reviewed) from the XXX [lanl.gov] server and decide for yourself how good they are.
    • High Energy Particle Physics is something of a special ball of wax because of the huge teams involved. For instance this paper has 44 names attached. If even half of those have seriously critiqued the paper then I'd be pretty confident there is nothing wrong the results.

      Of course I don't want to encourage "publishing to the press" as it's called, and in any case there will have to be more experiments to follow up this result.
  • to the drug industry. After all they did say:
    Peter Meyers, a professor of physics at Princeton University who was not part of the research team, said the finding is the "sort of crack" that "has been sought for many, many years."

    I'm sure this will the ultimate crack that crackheads everywhere will be searching for and paying top dollar for.
  • I propose "cowboynealon"...

  • what kind of crack? (Score:1, Redundant)

    by rnd() ( 118781 )
    Someone asked professor Peter Myers, "What kind of crack are you smoking?"

    Peter Meyers, a professor of physics at Princeton University who was not part of the research team, said the finding is the "sort of crack" that "has been sought for many, many years."

  • More Information (Score:3, Informative)

    by EccentricAnomaly ( 451326 ) on Friday November 09, 2001 @05:10PM (#2546116) Homepage
    A quick search of the Fermilab site found some more specifics than in the Washington Post article: a press release, the paper itself: [fnal.gov] A Precise Determination of Electroweak Parameters in Neutrino-Nucleon Scattering [lanl.gov], and some slides [PDF] from a Fermilab seminar. [rochester.edu]
  • Here's [rochester.edu] a good "plain english" explanation of what happened.

    Karma whore disclaimer: This link was stolen from the other article [slashdot.org] about this experiment.

  • /me applauds. (Score:5, Insightful)

    by Forager ( 144256 ) on Friday November 09, 2001 @05:13PM (#2546130) Homepage
    Since neutrinos are so small, most of the time they passed through the nucleus without affecting it. The frequency of collisions told scientists about the electromagnetic forces that affect how neutrinos behave -- the so-called weak forces. The scientists found slightly fewer interactions with one of the weak forces than had been predicted by the Standard Model, physicists' current description of fundamental forces and particles. Since the model is very precise, scientists concluded that the difference was significant. (emphasis mine)

    This is what I love about science. Here we have the Standard Model, formed from exhaustively detailed tests over the last 30 years. As the article states, the model is very precise, and slight deviations are significant issues. However, rather than scrap the entire idea, or announce that the tests were probably flawed, or decry the scientists who performed the tests as heathens and radicals, here we see that the community will embrace this new data and reform the model in such a way as to make it work.

    This is the beauty of science. If something doesn't work out the way it was supposed to, if a theory doesn't fit with the cold, hard data, the majourity of scientists will go out of their way to fix the theory (not the data). Scientists are always going out of their way to keep each other in check; at any given time one scientist may be checking some prominent theory or another. It keeps them honest, and while the system isn't fool proof, it's damn tight.

    Sometimes it's great to be a geek.

    ~Aaron.
    • Hum, sounds a lot like pro open source fanfare. I like that, but you're really uninformed if you think that when one scientist finds a lot of good evidence that something accepted is wrong, that all of a sudden all the other scientists will follow suit. That certainly is NOT the case. It has happened an afwul many times in scientific history that somebody comes up with very decent research and is plainly ignored by his colleagues for the good reason that they don't want to accept it. Reinaert

      • evidence? (Score:3, Insightful)

        by 3am ( 314579 )
        i don't believe you. ideas have momentum, but historically, science has gotten more and more accurate at describing the natural world.

        many times existing theory has inertia, but if the evidence is strong enough, the more correct hypothesis will subplant the weaker one.

        now, if you are going to accuse people who resist new ideas of small mindedness, then you are doing them a great disservice. Skepticism must be on both sides of a scientific dispute. Fawning over and prematurely accepting new theory is just as bad for Good Science as being to stubborn to accept that your idea is wrong.

        if you want to dispute this, show me some evidence. Recall that astronomy has gone from a geo-centric world (with heaven in the out spheres)to a helio-centric universe. Newtonian mechanics were replaced by general relativity. the whole history of science shows the same trends.

        • Got 'cher evidence right here. (Score:4, Interesting)

          by Fesh ( 112953 ) on Friday November 09, 2001 @06:10PM (#2546400) Homepage Journal
          Hold onto that thought, 'cause I'm about to blow a Mack truck-sized hole in it.

          Do a google search on Alfred Wegener, and you'll see a guy who got his ass kicked all over the place for proposing a theory that contradicted scientific understanding at the time. And was harassed as vigorously as any religious heretic. Want more? Here's the frigging link [nasa.gov].

          Through the hoop, nothin' but net.

          Do yourself a favor and check out Science's reaction to Darwin and doubters of Global Warning. Shocking behaviour all around, if you ask me.
          • So your saying science never embraced tetonic theory?
            If I came out with vague proof that squirrels are telepaths, the scientific community will scoff at me. but in time the truth will come out beause there are Scientists who will take the time to read my reasearch.
          • Overstated. you may have put a pin hole in it.

            You may notice that in fields where empirical evidence is less certain (evolution, geology) and massive time scales are involved, there is more controversy over new theory. This is because the body of proof needed to overturn existing theory is much more difficult to build. Additionally, Wegener did not seem to have an air-tight claim (from your NASA link): "Scientifically, of course, Wegener's case was not as good as Galileo's, which was based on mathematics. His major problem was finding a force or forces that could make the continents "plow around in the mantle," as one critic put it. Wegener tentatively suggested two candidates: centrifugal force caused by the rotation of the Earth, and tidal-type waves in the Earth itself generated by the gravitational pull of the sun and moon. " You may note that he was wrong on both causes...

            Anyway, an exception to the rule doesn't change the overwhelming trend in science to accept ideas on their agreement with experimental evidence.

            CLARIFICATION: I have little sympathy for researchers unwilling to work within the scientific process. An idea is the first part of research. Next you devise an experiment, and justify that it will prove your idea correct. Then you perform that experiment as accurately as possible. Then you see how the results from your experiment match your idea. If they don't, then you admit it. Anything else isn't real science.
            • Yah, I realized that once I read down the thread a little farther... *grin* The way I read your statement was that scientists never act like religious zealots facing a heretic. And I really thought that this was a case of violent rejection simply because the prevailing thought didn't happen to like the idea.

              And yeah, I was a bit cavalier with the wording there. As you can see, I thought I was replying to a much simpler challenge.

            • CLARIFICATION: I have little sympathy for researchers unwilling to work within the scientific process. An idea is the first part of research. Next you devise an experiment, and justify that it will prove your idea correct. Then you perform that experiment as accurately as possible. Then you see how the results from your experiment match your idea. If they don't, then you admit it. Anything else isn't real science.

              Nearly right. The wrong part is that the various parts of the operation require different skills, so they are usually done by different people. That means that there needs to be communication between them before the process is completed. It's wrong to call the original hypothesis a scientific result, but it's also wrong to dismiss it as fantasy. It's a hypothesis . The proposer of the first experiment to test the hypothesis is sometimes also the originator of the hypothesis, but frequently not in the original paper. And it's quite rare for the experimentalist to be the same person as the originator. And communication and discussion is needed at each of these stages.

              Equally, what the results of any experiment means is generally subject to further discussion and refinement. Usually after the fact, though in fortunate cases some of the discussion will take place before the experiment. (And here I'm simplifying, because each of these "individuals" is not a person, but rather a team of people.)

              I think that a recent coverage of Wegener by Stephen J. Gould (I forget the title, so read them all. They're worth it!) handled this well. He's generally entertaining as well as informative. (He does love his "punctured equilibrium" theory, but then I suspect that it's probably right. And he makes not bones about loving the theory partially because he was one of the creators.)
    • The scientists found a descrepancy with the Standard Model because they are in league with the Devil. Burn them! Burn them!

      Er, what were you saying?
    • Actually, the truly scientifically correct thing to do would be to duplicate the tests several times, just to make sure the deviation could be reproduced in a reliable manner.

      The results of any experiment should be called into question until several other people have done the same thing and gotten the same results. The whole point of this redundancy is to reduce the chance of a flawed experiment being accepted.

      Yeah, it's not as efficient. But science should be nothing if not reliable.
      • Regarding redundancy, it's not just to filter out flawed experiments, but to make sure the correct parameters are being considered. If one experimenter can reliably reproduce his results, but few others can, it means there might be a different cause of the results that wasn't anticipated.

        In subatomic physics, one such cause could be a security guard somehow getting access to the room where measurements are taking place, opening the door, and shining a flashlight into the room. Or, it could be something more subtle.

    • I'm sure there will be plenty who step on what these people are doing, because to disagree you only need a different belief and a means to communicate. But in the end, the disagreement almost always ends up finding the right answer.

      Falsehood requires a continuing string of liars or dupes, all repeating their tale the same.

      The truth is the same no matter who discovers it.

      Truth survives the argument by outlasting the lie, because truth can't die with its tellers. In this way, Science evolves an epistemology of things that we expect will be true no matter who tries it. It is the repeatability that is paramount, not the words that describe it or the people who wrote them or the institutions they represent.

      --Blair
  • The more I read about modern physics, the more it seems our current models are flawed. I recently read an article in 'wired' about programmable materials made from 'atoms' which do not contain a nucleus. Simply lots of electrons forced into atom-like patterns.

    I really wonder if we might not be better of throwing the physics textbooks out of the window and starting over again.

    • The more I read about modern physics, the more it seems our current models are flawed. I recently read an article in 'wired' about programmable materials made from 'atoms' which do not contain a nucleus. Simply lots of electrons forced into atom-like patterns.

      I really wonder if we might not be better of throwing the physics textbooks out of the window and starting over again.

      Bear in mind that "Wired" is not known for its contributors' understanding of science :).

      It sounds like a second-hand description of "quantum dot" technology. This is where you create a potential well in a conducting material and confine an electron within the well. Because the well is small, you get only certain energy levels permitted for the electron, just as in an atom. By changing the properties of the well, you change the properties of this "fake atom".

      There are many examples of materials where electrons aren't bound to individual atoms. Metals are a great example of this.

      All of this is perfectly consistent with the models of how electrons and atoms behave (look up "Schrodinger's Equation" in a first-year physics text for a description of the model used for this).

      Summary: Most perceived flaws are the result of bad or oversimplified explanations :).
  • At the risk of being slightly off topic, does anyone else get a little flustered with all the non-abolutes that seem to nearly accompany scientific papers? Examples from this very article:

    "...prompting physicists yesterday to announce that they might be on the verge of finding a new form of matter or energy."

    "While this discrepancy could be a fluke, then scientists who conducted the experiment said the odds were it represented something meaningfull..."

    "If some hidden matter or energy did cause the discrepancy..."

    "It could be a very big deal..."

    "It would be very exciting if we find another force"

    "...there is a high probablility that something is wrong with the theory"

    Just something to think about, not really a big deal, but it would be nice for people to just tell it how it is.

    • There are no absolutes in science, only hypotheses. And they are valid only as long as they fit with evidence. Evidence can be flawed, misinterpreted, and outright lied about.

      So no, it doesn't bother me. It would bother me if they were too confident.

      They are 'telling it how it is'

    • Re:Non absolutes... (Score:4, Insightful)

      by Wraithlyn ( 133796 ) on Friday November 09, 2001 @05:35PM (#2546227)
      Absolutes and hyperbole are the refuge of the close minded. They are simply not ruling out any possibilities without further confirmation.. this is an excellent practice I feel. They suspect they could be onto something big, but don't want to "over hype" it.

      "The wise man is the one who realizes that he knows nothing." - Socrates

    • Re:Non absolutes... (Score:2, Insightful)

      by michael ( 4716 )
      That's the mark of a good scientist.

      Really.

      When you have beliefs about the world and universe that are absolute, the term for that is "religion". Good scientists know that they don't know.
    • Science is not an answer!

      Science is the process of how to ask the question.

  • So that's why they call 'em High energy physicists (Score:3, Funny)

    by Johnny Vector ( 93021 ) on Friday November 09, 2001 @05:18PM (#2546150) Homepage
    From the Post article:
    Peter Meyers, a professor of physics at Princeton University who was not part of the research team, said the finding is the "sort of crack" that "has been sought for many, many years."

    I am always wary of results obtained by any physicists who have spent years and years seeking any sort of crack.

    (Sorry about that)

  • GOD: No, no, no..you have it all wrong..nuetrinos really are nuetral....Henderson had a bag of Cheetos for lunch and forgot to wash his hands.
  • ...for why the experiments don't agree with the theory. In theory, there is no difference between theory and practice. In practice, there is...

    Anyhow, if the results of all experiments had to agree with theory, undergraduate physics labs would have disproved all the laws of physics a long time ago... :-p


  • Its not that witches weighed as much as a duck... Its just that the duck has a higher dispacement of water pound for pound than your typical witch does. ;)

    And yes, PROPAGANDA is still up,

  • My daughter has the answer! (Score:4, Funny)

    by infinite9 ( 319274 ) on Friday November 09, 2001 @05:46PM (#2546290)
    My nine-year-old daughter and I were having a discussion about a month ago. She was studying the bohr model of the atom in her science class. I became interested when she started talking about the nucleus. So I asked, "which particles are inside the nucleus?" She didn't know so I described protons and neutrons. Then I asked, "which particles are outside the nucleus?" She thought for a minute and said, "Croutons?"

    My wife and I laughed for about a half hour, since she always steals the croutons from our salads at restaurants.

  • From Particle Physics (Score:3, Insightful)

    by MetricT ( 128876 ) on Friday November 09, 2001 @05:51PM (#2546314)
    Disclaimer: I used to study gravity, not particle physics. That said...

    Neutrinos only interact with other particles through the electroweak force (ignoring gravity for the moment). There are three bosons which "carry" the electroweak force, called W+, W-, and Z0. The discrepency with the Standard Model seems to occur with the Z0 (called the neutral current in the paper).

    There are several things it could be other than a new force. The scientists will have to eliminate all forms of background noise and detector errors, the possibility that it was just some sort of hadron resonance, and a lot of other things.

    It is amazing how sensitive particle experiments can be. I remember reading about one that had to filter out (among other things) the noise caused by the motion of the moon orbiting the earth in order to extract the signal.

    That said, I think they may be on to something.
    • Disclaimer: I used to study gravity, not particle physics.

      I remember reading about one that had to filter out (among other things) the noise caused by the motion of the moon orbiting the earth in order to extract the signal.

      I'm wondering if perhaps you haven't gotten confused and are thinking about LIGO (Large Interferometry Gravitational Observatory). I would be rather surprised if particle experiments could pick up the motion of the moon. Among other things the moon doesn't move significantly over the span of each event, and particle detectors and what not are usually concerned with EM effects largely neglect gravitational effects.

      On the other hand I do know that LIGO has to contend with a laundry list of crazy sources of interference, including cars on the nearest road, lunar motion, continental drift, and tumbleweeds bumping into the research buildings. That is what you get when you want to measure average displacement of a macroscopic object to within a fraction of an atomic nucleus.
  • Okay, if you do 400 experiments, you can expect 1 would be in the 1-in-400 bin on the tail of the histogram.

    I'm sure the Standard Model has endured way more than 400 tests.

    A few more labs need to repeat this experiment to make sure the result is accurate.

    --Blair

    P.S. If a neutrino is chargeless, how do you "fire" one at something?
    • P.S. If a neutrino is chargeless, how do you "fire" one at something?

      How about a beam of relativistic charged particles that decay and release neutrinos as a byproduct? Relativistic beaming means most neutrinos in our rest frame are being beamed in the direction of propagation.

    • Re:Not rare enough. (Score:2, Informative)

      by osu-neko ( 2604 )
      I'm sure the Standard Model has endured way more than 400 tests.

      Err, actually, this part of the standard model has not borne anywhere near that many tests. The number four comes to mind, two of which were not accurate enough to pinpoint this problem, and two of which have suggested it's wrong. So not, it has not in fact endured any testing on this particular issue. So far, it has failed every time. The only problem being, "every time" means roughly "twice", as I understand...

    • Okay, if you do 400 experiments, you can expect 1 would be in the 1-in-400 bin on the tail of the histogram. I'm sure the Standard Model has endured way more than 400 tests.

      Not via this specific experiment it hasn't! You're comparing apples and oranges. That 400-1 test is the probability that this given experiment turned out the way it did by pure chance. If they repeat the experiment and get the same results then you will have a P-value of 160,000 to 1 to explain.

      P.S. If a neutrino is chargeless, how do you "fire" one at something?

      Well, it isn't like loading a gun with bullets and then shooting them. Accelerating an existing neutrino is pretty hard. Usually what you do is create them when you fire them.
      A trivial example would be putting cobalt-60 (beta emitter) in a solenoid. Electrons fly out one end and the antineutrinos come out the other.
      • >Not via this specific experiment it hasn't!

        Yabbut, that's the point. You do 400 experiments, then everyone goes ga-ga over one that has a strangeness quotient of 400?

        >If they repeat the experiment and get the same results then you will have a P-value of 160,000 to 1 to explain.

        Precisely, exactly, and perfectly the reason I said more labs need to try it. Push that improbability right out of the realm of chance result in the number of experiments it is possible to perform in the course of human history. I mean, even if it wasn't true, if it happens every time you do the experiment, it might as well have been true.

        >A trivial example would be putting cobalt-60 (beta emitter) in a solenoid. Electrons fly out one end and the antineutrinos come out the other.

        Interesting. But then the e-field has to influence the generation of the electron, not just its momentum after it is generated. If you fire a bullet from a gun, the gun goes the other way; if you suck a bullet out of a gun, the gun would tend to come along. So, does the e-field align the electron and the neutrino before the neutrino is fired from the electron? And if the neutrino isn't charged, how the hell does that happen? If there's a proton involved (and there is, because this is neutron decay, right?) then the proton-electron dipole would be aligned, and you're saying the neutrino comes out by going through the proton, or around it, like a snapped rubber band...

        Sorry about all the naff questions. I'm good at physics, but I stopped studying nuclear physics at the early graduate level when they started offering me money to do semiconductor design.

        --Blair
  • Geee, maybe I can patent it.

    .
  • It is not the first time that the Standard modell has been modified.

    For example in the begining there has been only
    one generation of quarks and leptons.
    (namely: up and down) But on electron collision experiments showed that there must be new generations: (now called
    strange - charmed and beauty - truth.)

    Until 1995, where experimental evidence was found, the truth quark was only a postulate based on symmetry considerations.

    The same applies to symmetry conservation. For a long time CP (Charge conjugation with Parity) was considered conserved. But an experiment on T (Time inversion) violation showed if CPT was to be conserved, CP must be violated. Again the standard model had to be adabted.

    And at the CERN (Eruopean Nuclear Research Center) in Geneva they believe, that they have fond some evidence for the so called Higgs particle, which is the cause for the mass of particles. A proof for the Higgs particle would be an enhancement for the Standard Model

    Those examples show that the Standard Model of Particles and Interactions is not a static one.
    It is almost like the linux kernel - if you permit this comparision - people send in patches.
    If a patch is useful it will be released for the masses :-)

    Maybe we are entering a odd release stage now :-)

  • Not that significant (Score:2, Insightful)

    by zwalters ( 532390 )
    I wouldn't make any long term plans based on this paper. The "one chance in 400" is misleading -- if you look at the paper, what it's really saying is that their experimental result differed from their theoretical result by three standard deviations (three sigma). On the face of it, this isn't very impressive. The trouble with straightforward statistical analysis in this fasion is that particle physics is hard. Experiments are being done at the limits of detectability, and often in ways that have never been done before. Because of this, it's extremely hard to tell what one sigma is, since it's entirely possible (and somewhat likely) that you just don't understand the pitfalls yet. Particle physicists have a rule of thumb for cases like this: a six sigma effect pans out about half the time. This is only a three sigma result, so adjust your expectations accordingly. A result like this is worth publishing, but won't persuade many people unless followup experiments get the same results (with *much* better statistics).

    • Re:Not that significant (Score:5, Informative)

      by Zeinfeld ( 263942 ) on Friday November 09, 2001 @08:36PM (#2547033) Homepage
      I wouldn't make any long term plans based on this paper. The "one chance in 400" is misleading -- if you look at the paper, what it's really saying is that their experimental result differed from their theoretical result by three standard deviations (three sigma). On the face of it, this isn't very impressive. The trouble with straightforward statistical analysis in this fasion is that particle physics is hard. Experiments are being done at the limits of detectability, and often in ways that have never been done before.

      As a former experimentalist in the field (they gave me the Phd so I couldn't be all that bad) I am not getting excited.

      The problem is that the experiments are simply not accurate enough to jump up and down in celebration for such a miniscule deviation.

      What I am really suspicious about is that the number of observations is much lower than expected. That can happen because you just missed some particles you should have seen.

      You can have a deviation that is 'significant' at twenty or a hundred standard deviations and it can still be the result of experimental error rather than a flaw in the standard model.

      Given the way the physicists write their programs I would not be at all surprised if this turns out to be no more than the result of a flaw in PAW or GEANT. A physicist will go off to beg congress for a billion dollars to four experiments on the same accelerator (e.g. LEP) so that each can cross check the results of the other. Then they will all share the same analysis programs even though they are known to be riddled with bugs. And don't start on about the Web, first off the Web code was not built on a twenty year old code base from the dawn of Fortran, second there were multiple versions of the code written from the very start. In 1992 there were 10 browsers and at least 5 Web servers.

      • I don't know what analysis tools NuTeV used, but there is at least some competition to the mess called CERNLIB these days. Many "younger" collaborations have switched over to ROOT [root.cern.ch], which is mostly a clean break from the past.

        Nevertheless, its primary developers are Rene Brun and Fons Rademakers (familiar names from the old days), and at least one crucial bit of code (the MINUIT minimization engine) has been run through f2c and recycled, so it's not fully independent. Seriously, it would be very useful if someone were to rewrite MINUIT in an intelligible style.

  • what have they been smoking? (Score:3, Funny)

    by option8 ( 16509 ) on Friday November 09, 2001 @07:56PM (#2546907) Homepage
    what have these guys been smoking? oh yeah, here it is in the article:

    "Peter Meyers, a professor of physics at Princeton University who was not part of the research team, said the finding is the "sort of crack" that "has been sought for many, many years."

    that explains it all to me...

  • Blood Sport (Score:2, Interesting)

    by Tim12s ( 209786 )
    One of my university leacturers told me why he decided to go the mathematics route.

    "Mathematics and Physics are the last true blood sports. Kill one bird an EVERYTHING goes."

    Funny when you realise the ramifications of this since ALOT of work needs to be reevaluated, etc, even when the results are "statistically" correct, since the explinations and models of how things achieved some result are now totally different.

    -Tim

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