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What is empty space ?

  1. Mar 25, 2009 #1
    What is "empty space"?

    I always hear this term: "empty space." It is synonymous with "vacuum," but I am having trouble understanding either of these two ideas.

    How can space be "empty?"
  2. jcsd
  3. Mar 25, 2009 #2


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    that's the pessimist view :rolleyes:

    I think that space is full, of …

    well …

    space! :smile:
  4. Mar 25, 2009 #3


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    Re: What is "empty space"?

    I would think it is impossible to have a truly empty space.


    How would one find it?
  5. Mar 25, 2009 #4
    Re: What is "empty space"?

    The permeability of empty space is u0 Henrys per meter, and the permittivity of empty space is e0 Farads per meter, so the impedance of empty space is sqrt(u0 / e0)) = 377 ohms, and the velocity of light is sqrt(1 /(u0 e0)) = 2.9979 x 108 meters per sec. Other than that its pretty much nothing at all (except dark matter, dark energy, neutrinos, cosmic rays, microwaves, gravity, photons, etc.)
    Last edited: Mar 25, 2009
  6. Mar 25, 2009 #5


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    Re: What is "empty space"?

    You can add the collective intellect of my in-laws to that list... :grumpy:
  7. Mar 25, 2009 #6
    Re: What is "empty space"?

    higgs field
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