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If 99% of an atom empty, and if we say that our body is made of atoms stacked together, then why is our body a solid object, rather than 99% hollow.

I have one probable answer that I think might be correct. Referring to the image belowenter image description here

The one on the left (bigger circles) have 99% of the space empty. Now if we reduce the size of circle, then even though the space is 99% empty, but the overall empty space is very less (compared to bigger circle).

If we take this to an atomic level, then the size of the atom is so slow, that we can imagine a small dot in the center, surrounded by very small empty circular space, and then another atom stacked next to it. Now, the 'empty circular' space is so small, that for all practical purposes we can assume the two centers of circles to be next to each other. And hence our body (or any solid body) does not seem empty.

But then, why doesnt light pass through a solid body. Even though the empty space is very less, there still is empty space right? Is it that the size of photon is much bigger than the size of an atom and hence it is unable to pass through that empty space?

I understand that I am not taking into consideration the inter atomic forces, but even if two atoms were very tightly bonded to one another, there will still be some empty space between them (as described in the diagram).

Kraken
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  • Kinda... But the atom isn't completely empty – Jimmy360 Jun 09 '15 at 14:43
  • Yeah, it's not completely empty, but still there'a nucleus and then electrons orbiting the nucleus. The space inbetween is still empty right? – Kraken Jun 09 '15 at 14:45
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    No. This is a major misconception based on a naive particle picture. See this thread for further input: http://physics.stackexchange.com/q/126512/ – Martin Jun 09 '15 at 14:47
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    This "but still there'a nucleus and then electrons orbiting the nucleus" is more wrong than right. The electrons are not little balls and they are not in orbit. They are quantum object which exist in space-filling orbitals (quantum states). The atom isn't empty except in school books. – dmckee --- ex-moderator kitten Jun 09 '15 at 14:48
  • empty of matter but filled by a lot of fields –  Jun 09 '15 at 15:07
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    @igael: no, that isn't true. The matter/energy making up the electrons is distributed continuously through the atom. – John Rennie Jun 09 '15 at 15:08
  • @JohnRennie: yes, you are true ! it's not rigorous but not so false in a popular physics image. Mean density is the same with Bohr or modern atom ... –  Jun 09 '15 at 15:17
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    @igael: the highly misleading popular physics image is exactly why we keep getting questions like this. You are doing the world no favours by attempting to perpetuate an analogy that is seriously flawed. – John Rennie Jun 09 '15 at 15:19
  • it's just comments, no ? did you find a bad approximation ? well, thank you very much , I understand now you didactic point of view. Note that atomic electron density is less than the dust density in many spatial environment –  Jun 09 '15 at 15:25
  • @igael: I have to agree with JohnRennie and the others here: we are not trying to defend popular but false physics pictures here. This is one of the few places on the internet where you can be given the real deal, as raw as it may be after having been mislead by generations of poor popular science writing. Consider this: take two strong rare-earth magnets and try to push the repelling poles together! Are you getting the feeling that space is empty between those magnets? Now consider that the forces inside of atoms are many orders of magnitude stronger than that! Still think atoms are "empty"? – CuriousOne Jun 09 '15 at 19:17
  • @CuriousOne: too much comments about one word in a comment. What is this trial ? –  Jun 09 '15 at 19:53
  • @igael: Your comment is 100% false because it is so short: matter is a state of a field. There is nothing else but that field. The force between two magnets is simply a different expression of the same field that causes the existence of matter. We simply discovered magnetism earlier than the color force and the electroweak force because it's technically much easier to explore. That's a historical artifact, not a fundamental difference of nature. In any case, what invited the negative responses was your attempt to justify it with an outdated image. – CuriousOne Jun 09 '15 at 19:58
  • @CuriousOne : I wrote "empty of matter but filled by a lot of fields" . Electron are just fields excitations. I was answering to the question in the title. What else ? –  Jun 09 '15 at 20:07
  • @igael: Matter is nothing but fields. There is no matter that is not a field. Maybe we misunderstood your comment. Anyway... let's end it here. – CuriousOne Jun 09 '15 at 20:12
  • @Kraken : neutrinos are a good field to investigate. It's a matter of interactions ... –  Jun 09 '15 at 20:21

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