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Interesting Fact: Is it true?

  1. Sep 3, 2003 #1
    I recently read in a book by Deepak Chopra that the human body is actually 99.9999% empty space... Is that true?
  2. jcsd
  3. Sep 3, 2003 #2
    I have read some Deepak Chopra's books! and you will be agree with me that we can only understand him in a spiritually way...

    About the question, all bodies composed by atoms at the universe are 99,9% empty space, because the 99,9% of the volume of an atom is empty (the space between the nucleus and the electrons), so, it's not a special property of the human body...

    It's a funny curiosity, I know!...
  4. Sep 3, 2003 #3
    Hmm.... I didn't know that... Interesting.....
    So, did you like his books? Are they worth while?
  5. Sep 4, 2003 #4


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    Depends on what you mean by empty space of course. With QM, what we think of as "empty" space is far from empty.
  6. Sep 4, 2003 #5
    Well, it depends on what are u looking for... I read the last one many years ago and I found it... funny... but since I have my spirituality satisfied :wink: I have nothing to do with these books...

    hehehehehehehe :smile: of course! I think we were talking in a classical way...

    By the way, I have heard that the results of the two experiments of the Cassimir force had a discrepancy between them of around two magnitude ordes ( ·100, I don't know if those are the words in inglish) You know if it is thru?

    and, since the two "plates" were only a few-atoms-size, they couldn't compare it with the gravitacional force...

    Could the Cassimir force be just the gravitacional force? It would be amazing!
  7. Sep 5, 2003 #6


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    No, they ruled out gravity as the cause of the Casimir effect. The effect has all the earmarks of being just what Hendrik Casimir hypothesiszed, a difference in wave pressure from the virtual particles in the vacuum, due to the fact that those outside the plates could have arbitrarily long wave lengths, while those between the plates were limited in wave length by the spacing of the plates. So there were more particles outside than inside, which led to a pressure on the plates.
  8. Sep 5, 2003 #7
    yeah... I know the Casimir effect... and since it doesn't depend on mass is impossible make a relation between gravity... but since they couldn't compare them experimentally, we only have the theory, that is not so developed due to its "youth" and to the less people that has worked on it (if we compare with other physical phenomenas)...
  9. Sep 5, 2003 #8


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    Casimir's prediction goes back to the late 1940s or early 1950s. He based it on the quantum vacuum which was then about 10 years old, or in its early form as the Dirac sea, 20 years old. The QV is based on taking the uncertainty priciple seriously, and that goes back to the foundation period of QM in the 1920s.

    As for the experiments, I would guess they are abour 20 years old. The Casimir force doesn't come from the edge of quantum mechanics, where it might be seen as shaky, but from the core of QM.
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