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Fundamental Constant Possibly Inconsistent

Posted by Zonk on Fri Apr 21, 2006 12:29 PM
from the those-wacky-constants dept.
dylanduck writes "Cosmologists have begun thinking that yet another fundamental constant of nature is, er, not constant. The constant in question is the ratio of a proton's mass to that of an electron. It governs the strong nuclear force but there's no explanation for why that ratio should be constant. If true it would provide support for string theory, which predicts extra spatial dimensions." From the article: "Researchers at the Free University in Amsterdam in the Netherlands and the European Southern Observatory in Chile discovered the variation in mu. They did it by comparing the spectrum of molecular hydrogen gas in the laboratory to what it was in quasars 12 billion light years away. The spectrum depends on the relative masses of protons and electrons in the molecule."
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  • by Anonymous Coward on Friday April 21 2006, @12:31PM (#15174423)
    ...that God is a woman.
  • Haven't I heard that one before?

    http://www.imdb.com/title/tt0089869/ [imdb.com]

    • by dc29A (636871) on Friday April 21 2006, @12:35PM (#15174448) Homepage
      Farnsworth: These are the dark matter engine I invented. They allow my starship to travel between galaxies in mere hours.

      Cubert: That's impossible. You can't go faster than the speed of light.

      Farnsworth: Of course not. That's why scientists increased the speed of light in 2208.
  • by Snarfangel (203258) on Friday April 21 2006, @12:37PM (#15174469) Homepage
    ...isn't constant, either. Perhaps we can rename them "fundamental variables."
    • No, constant is good. It's just that for very large or small values of the constant, it's sometimes different.

      1!=2 is, for example, always true, except for with very small values of 2 or very large values of 1. Possibly you need both small values of 2 and large values of 1.
      • Urgh... that will mess up optimization.

        Well, that's what God gets for using C++. You think you've got a well-designed system, then you realize that to make your next set of changes work you're going to have to throw in a bunch of const_casts or mutables.

        You can tell He's new to object oriented programming, too - he's got this whole overeager class hierarchy of tau derived from muon derived from electron, top derived from charm derived from up, and on and on, but then when it's finally time to put together the universe He gets sick of the whole thing and builds all His matter from the base classes!
  • by iainl (136759) on Friday April 21 2006, @12:38PM (#15174480)
    ...if the ratio is changing, doesn't that mean that either electrons or protons (probably both) have changed mass?

    How the hell does that work?
    • by PiMuNu (865592) on Friday April 21 2006, @12:53PM (#15174622)

      Don't forget the proton is a composite of quarks. So the mass of the proton is a function of the mass of the quarks and the binding energy. A hack but E=mc^2, so m(proton) = m(quarks) - (binding energy)/c^2. The binding energy changes if the strengths of the forces that bind it change. This means that a change in the electromagnetic force (e.g. changing alpha fine structure constant) or the strong force will change the mass also. Of course, the mass of the electrons or quarks could have changed as well :P

  • Pi = 3.
    • by ameoba (173803) on Friday April 21 2006, @01:43PM (#15175117) Homepage
      Arbitrarily changing universal constants can be a bad thing.

      I remember one time, in my youth, while partaking of illicit mind-altering substances, looking at a window. More specifically, a small piece of stained-glass hanging from the window. Hanging by a suction cup.

      A circular suction cup.

      This piece of stained glass had been hanging on that very window for years.

      Deep in thought, looking at this stained glass, I thought to myself "You know, if I was God, I'd probably round off pi to a million decimal places or so - it wouldn't really effect anything and it would make things much simpler". At which point, this stained glass, hanging from a circular suction cup, which had been there, unmoving, for years, due to a failure in the circular suction cup, fell to the ground and shattered.

      I learned my lesson - don't mess with universal constants.
  • by davidoff404 (764733) on Friday April 21 2006, @12:46PM (#15174561)
    Where the hell did they get that from? String theory is fully compatible with the idea that the constants in nature are actually constant. After all, string theory has been developed to fit the data and nobody has been able to provide any evidence that this is not the case in the real world. On the contrary, changing fundamental constants would require more finessing of string theory in order to fit the data.

    And yes, before you start, I know what I'm talking about.
  • and says ....
    "I think I have lost an electron!"

    Another atom asks..
    "Are you sure?"

    The atom says
    "I'm positive!"

    I'll be here all week, enjoy the veal.....

  • FORTRAN (Score:5, Funny)

    by Detritus (11846) on Friday April 21 2006, @01:57PM (#15175298) Homepage
    And they said that the ability to change the values of constants at run-time was a bug. Ha! Take that, you quiche eaters.
  • What is mass? (Score:5, Insightful)

    by wanerious (712877) on Friday April 21 2006, @02:03PM (#15175375) Homepage
    The results are potentially interesting, though I'm initially skeptical of *any* measurement of phenomena back at this redshift claiming accuracy to some tiny fraction of a percent. And, to be picky, astronomers virtually never say that an object is "12 billion ly away" --- we usually refer to their "location" via the redshift number, as this is easy and unambiguous.

    But a change in the ratio of their masses might shed some light on exactly what mass is to begin with. Yes, it's the ability to curve space, and also the resistance to being accelerated. But never mind the p/e ratio being fixed, no one really understands why the individual values are what they are to begin with.

    For example, something that always gets me is the muon. Identical to the electron in virtually every way (charge, apparent point-like non-structure, lepton) except is has a mass roughly 207 times as great. Why? What does it have 207 times more of than the electron does to make it 207 times more efficient at curving space? What kind of goo is there that makes it 207 times more resistant to acceleration? And if it's truly a fundamental particle, as we suspect for leptons, why 207-point-something?

    It nags at me.

    • by Anonymous Coward on Friday April 21 2006, @12:56PM (#15174657)
      And yet you have no idea where the clitoris is.
    • Re:Does this mean (Score:5, Interesting)

      by maxwell demon (590494) on Friday April 21 2006, @01:15PM (#15174847) Journal
      that I face the risk that the first 100 digits of PI that I have memorized could change, and the knowledge becomes useless?

      Well, that was true since Einstein: The value of pi as you learned it is only valid in Euklidean (flat) space, and our space is Riemannian (curved). However, to your relieve, the Riemannian space is locally Euclidean, so if you restrict yourself to a small enough volume, your 100 digits are accurate again. Unless you get into trouble with quantum physics (I'm now too lazy to calculate if you could get 100 digits of pi right on Earth without getting close to the Planck length).
    • by Valdrax (32670) on Friday April 21 2006, @03:02PM (#15175998)
      This is actually true, I do know the first 100 digits by heart.

      Out of curiosity, are you an excellent driver?
      • by iamlucky13 (795185) on Friday April 21 2006, @03:28PM (#15176229)

        First of all, to stay a little bit on topic, the theoretically observed change in mu is extremely small. Physicists don't know why mu should be about 1836 instead of about 1836.5 or 3 or 11,296,428. My understanding is (and I am not an expert on this), that really small change in mu like we're talking about here wouldn't significantly affect the universe and it would still look largely like it does, but somewhat small change in mu, like an order of magnitude would, a lot. This bugs physicists because they don't know why it is what it is. Why do we have the universe we have instead of something drastically different like one that collapsed or blew apart 10 minutes after the Big Bang? The only answer they can offer is the anthropic principle: It is the way it is because if it weren't, we wouldn't be here to notice.

        The existence of God does not hinge on the constancy of mu. This doesn't even disprove intelligent design, which is as bad from a theological perspective as it is from a scientific perspective, being vain in both schools. Several prominent Catholic theologians have stated as much. The perplexing question of why fundamental particles are the way they are and therefore allow us to exist does not constitute a proof of God's existence, but they are rather suggestive.

        For the record, I think a brief discussion of creation concepts would be appropriate in social studies (as part of a survey of religions) or in philosophy classes (the study of being) in public schools, but not in science. I want to point out that if God created the phenomena which allows and upon which we base our science, it's unlikely that we would be able to prove or disprove His existence directly through science.

        The concept of "Faith" was a magnificant and powerful creation--a tool that can allow a few people to control millions--and I'd like to meet the amazingly talented P/R man who figured out how to tag such a horrid, evil concept as "Good".

        Question Everything

        I wasn't going to reply, but it seemed worthwhile to Question this statement. Who is controlled here? The billions of faithful who find meaning in life? In what way are we controlled? By adherence to principles that are conducive to the betterment of mankind like "love your neighbor as yourself" and "Thou shalt not kill?" What is the gain for these scheming, evil leaders and their P/R man? You don't exactly see a lot of priests pimping it up with 22" rims on their Lincolns and an escort on each arm. Celibacy, the difficulties of working with a faith-community, itchy robes, and a badly off-key choir...now there's a good reason to cook up a religion. I'm willing to guarantee you the overwhelming majority of religious leaders really do believe in the faith they profess. Yes there is a large degree of misdirection and a few unscrupulous groups that are nothing more than pyramid schemes or printing companies, but the basic precepts of most religions out there are founded, promoted, and executed with good intent.