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Fundamental Constant Possibly Inconsistent 317

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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Fundamental Constant Possibly Inconsistent

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  • Some comments (Score:3, Informative)

    by Anonymous Coward on Friday April 21, 2006 @12:48PM (#15174575)
    Historically speaking, there have been many claims in the past about various fundamental constants varying with time, and pretty much all of them have eventually not been corroborated by independent experimental groups. So take this with a large grain of salt.

    Also, with regard to string theory... well, string theory is more or less compatible with practically any scenario you can think of, because it's so flexible (to phrase it charitably). Any "new physics" can generally be claimed to "support" some string-inspired model. This does not in itself constitute strong evidence for string theory (since you can cook up specific non-string models too).

    Here is a link to one string theorist's (opinionated) blog regarding this issue []. He notes that this ratio being constant is also consistent with string theory (and is what he believes is likely to be true).
  • by davidoff404 ( 764733 ) on Friday April 21, 2006 @12:58PM (#15174676)
    I think a bigger issue is that ANYTHING can be compatible with string theory.

    This isn't even remotely correct. The easiest way to see this is to consider bosonic string theory and look at the manner in which the Virasoro algebra constrains physical states. It most certainly does not allow anything to be true. Quite the opposite in fact, it places heavy constraints on what is and is not allowed in a consistent string theory.
  • Re:Other constants (Score:2, Informative)

    by tylersoze ( 789256 ) on Friday April 21, 2006 @01:01PM (#15174704)
    Well mathematical constants like pi really are constant which I would hope would be obvious. :) Pi doesn't have anything to do with the warping of space, it's just a value that is defined to be the ratio of the circumference of a circle to its diameter in flat Euclidean space. Fundamental "constants" are just values plugged into physics equations that we just happen to assume to be constant. If we find that they're not constant then we really shouldn't be calling them constants.
  • The PRL paper (Score:3, Informative)

    by jlkelley ( 35651 ) on Friday April 21, 2006 @01:08PM (#15174785)
    For those interested in the actual paper (Phys. Rev. Lett. 96), the PDF is available on the researcher's publications page: []
  • by trigonalmayhem ( 938527 ) on Friday April 21, 2006 @02:12PM (#15175453)
    Remember when the force of gravity was a constant?

    Well for simple calculations about things on the earth's surface it still is, but as soon as you widen your perspective a little bit you have to start reworking where that number comes from. I don't see how this is much different than that. They look a little further and realize another 'constant' can also vary based on some principle they will hopefully figure out later with more observation.
  • by budgenator ( 254554 ) on Friday April 21, 2006 @02:39PM (#15175773) Journal
    I thought it was E^2 = m^2C^4p^2q^2 for some strange reason of course i'm merely a guilded missile technician, not a rocket scientist

"Nature is very un-American. Nature never hurries." -- William George Jordan