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Is 99% of the volume of the universe empty?

  1. Oct 24, 2007 #1
    If you look at the size of the amount of empty space in an atom, compared to the tiny size of the nuclues, does it not mean that the universe is nearly entirely empty? like 99% empty?
     
    Last edited: Oct 24, 2007
  2. jcsd
  3. Oct 24, 2007 #2
    Is it not something to do with the fact that light does not have a wavelength small enough for us to see the spaces, as they're so small... so we have to use gamma rays ones and what not? I really have no clue... just guessing!
     
  4. Oct 24, 2007 #3

    Gokul43201

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    No, it does not.
     
  5. Oct 24, 2007 #4
    care to elaborate on that? what is inbetween the nucleus and their outer energy state if it is not empty?

    i suppose you have fields like electric fields and magnetic fields in between, but they are metaphysical and have no real existence
     
    Last edited: Oct 24, 2007
  6. Oct 24, 2007 #5
    First, the emptiness is not 99%, there are more nines.
    I think when we look at it (the screen), we cannot see the empty space simply it is so tiny. In adition, what we see or we sense is light which comes from electron shells.
     
  7. Oct 24, 2007 #6
    Yeah, i suppose that actually the electrons emit their photons every time they transcend an energy state, so the light is actually spread out evenly between the outer electron path and inner electron path. Thats the problem with visualizing electrons as particles, they dont take up much space, when infact they are more like waves of potential.

    Anyway, you definately you cant see that small anyway, so there must be another part of the mechanism that makes you see. Does the eye pick up individual photons wavelengths, because i would have thought that photons were too small for a cell to adequately detect. Or does it somehow average the wavelengths of a group of photons. whoops, i should've put this in a biology thread :uhh:
     
    Last edited: Oct 24, 2007
  8. Oct 24, 2007 #7

    russ_watters

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    Many, many, many, many, many more nines. If I had to guess (too lazy to calculate), I'd guess the universe would be 10E-50 to 10E-100 % matter by volume.
    Crazy.
     
  9. Oct 25, 2007 #8
    In first approximation, the universe is now totally empty.
     
  10. Oct 25, 2007 #9

    Garth

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    My head then must be a typical member of the universe at large!

    Garth
     
  11. Oct 25, 2007 #10

    cristo

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    But clearly a first approximation is not valid for the universe, since it does not give an accurate picture!

    The average matter density of the universe is something of the order 10 protons per cubic metre.
     
  12. Oct 25, 2007 #11
    Not that bad. The universe consists of not only mass but mass and energy, which can convert into each other via Einstein equation. There are many other things like forces, lights, fields ect that almost fill the universe if not completely.
     
  13. Oct 25, 2007 #12
    Hmm, maybe you better define "empty".

    You might want to note that the universe is "filled" with quantum energy, from photons, to neutrinos, to energy waves of all kinds. There are plasma clouds in space between the stars, so space isn't really devoid of atoms either. In the sense that solar systems are separated by light years in some cases, yes, space is rather "empty" (of stars and planets) especially if you're stuck half way in between solar systems. It's not "empty" in terms of lack of energy however. In fact it's full of quantum waves of energy and a variety of identified particles.
     
  14. Oct 25, 2007 #13
    Which makes sense: if the universe is boundless then there is an infinite amount of space to fill with a finite amount of matter.
     
  15. Oct 25, 2007 #14

    Gokul43201

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    An atom is completely occupied by its constituent protons, neutrons and electrons. It is 100% filled, not 99% empty. The volume fraction of an atom where the mass density is zero, is 0% of the volume of the atom. Of course, the electrons occupy most of the space, but there's no reason to treat them as though they shoudn't count.

    I think you are asking what occupies the space between the nucleus and the outermost electronic orbitals. The answer is: electrons.

    Did you just refer to electric and magnetic fields as metaphysical quantities?
     
  16. Sep 2, 2011 #15
    Roughly speaking, there is one atom (mostly hydrogen) of matter per cubic meter of the space in the universe. Considering the size of an atom, Radius = 1/10,000,000,000 meters, the universe is 99.99...% empty!
     
  17. Sep 2, 2011 #16

    Ryan_m_b

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    Welcome to Physics Forums afalaki, if you look in the top left above peoples names you will see that this thread is four years old! Posting on old threads is discouraged here.
     
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