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Planck Distance proof?

  1. Mar 3, 2006 #1
    Has the planck distance been proven to exist and be real? I thought up a way to mabey prove it. Just don't want to beat a dead horse and spend 2 weeks of my vacation working on something that's been done.

    -Disclaimer. I am not onto something here. I am a geneticist, not a quantum physicist, on vacation. There was some sleep-dep and a lot of coffee and some computer gameing involved in me thinking this up. Don't get your hopes up:P
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  3. Mar 3, 2006 #2

    Meir Achuz

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    You would still be killing a dead horse.
  4. Mar 3, 2006 #3


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    Theres nothing to prove really, its an order of magnitude quantity based on purely classical dimensional analysis in 'god given' units where c=G=hbar=1, eg the spot where gravity and everything else start to be comparable in magnitude. Various theories of quantum gravity can move that around somewhat based on more serious calculations.

    All it is really is a regime, not a precise number, where we expect quantum mechanics to start to be important for a proper theory of gravity.
  5. Mar 3, 2006 #4
    The only way to prove the Planck distance exists would be to measure it somehow. I don't think the experimentalists are up to measuring something that small yet. As far as theory is concerned, I know the string theorists, at least, use it as a lower limit cut-off for distance. This helps them avoid certain infinities in their calculations. However, there is no real reason I know of to suspect that the Planck distance (mass or time) even mean anything real. At this point it's just numbers games.

  6. Mar 3, 2006 #5


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    I cannot realisticially offer you any encouragement since you run the risk of wasting your time on this project, but the direct answer to your question is NO
    the planck length has NOT yet been proven to have a real physical existence

    so if you spent 2 weeks writing up your idea or doing experiments, then you might fail but at least you would NOT be duplicating already existing scientific results

    You might fail to produce anything that you could publish in a scientific journal---and your attempt might be misguided---but I do not think that is necessarily a reason not to spend the time. If you spend 2 weeks thinking about the Planck length and trying to devise some theory or experiment to show that it is built into nature, then you would at least LEARN SOMETHING.

    If you have ideas of how to experimentally detect some new behavior at the Planck scale that would show that this scale has a real physical meaning, you are welcome to post them at this thread and tell us about them.

    then people will hopefully criticize you and try to find mistakes. this is often very helpful.. if you are a geneticist, then you know that having a critical audience to explain things to helps to get ideas in order

    I know of one experiment that has been planned to test for a kind of Planck-scale behavior. But it has not yet been done. The experiment will be done at the earliest in 2007. If the Bush administration cuts the science budget too much then the space mission planned for 2007 that could test this will not be done even then
  7. Mar 3, 2006 #6

    Ok yes:) Thank you this is what I was looking for:)

    Yes, I fully agree I am a bit off the normal rocker, and probaly will just be wateing my time, but mabey I'll enjoy myself and learn something intresting:)

    Thanks, i'll bring it back to you after I do some math and ask a few people I know IRL weather I added 2 + 2 and got 5:)
  8. Mar 29, 2006 #7

    Hans de Vries

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    (edit: This was a rectifying response to a post which had a totally wrong
    value for Planck's length plus a reference to a **** site, :^) Hans)

    Planck's length is 1.61624 10-35 meter.

    Some background is here:

    Regards, Hans

    Planck mass _________ 2.17645(16) 10-8 kg
    Planck temperature ___ 1.41679(11) 1032 K
    Planck length_________ 1.61624(12) 10-35 m
    Planck time __________ 5.39121(40) 10-44 s
    Last edited: Mar 30, 2006
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