This question may not come in the bracket of quantum mechanics but

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Discussion Overview

The discussion revolves around the question of what gives the illusion of solidity in atoms, particularly considering that most of an atom is empty space. Participants explore various explanations related to electromagnetic forces and quantum mechanics, including electron repulsion and degeneracy pressure.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that the illusion of solidity is primarily due to the electromagnetic force, specifically the repulsion between electrons.
  • Others argue that electron degeneracy pressure is a significant factor in explaining solidity, suggesting it may prevent materials from passing through each other.
  • A later reply emphasizes that while both effects are distinct, the first (Coulomb repulsion) is essential for understanding the solidity of non-degenerate matter.
  • One participant mentions a lecture by Brian Cox that discusses these concepts, indicating that degeneracy pressure is highlighted as a cause of the illusion of solidity.

Areas of Agreement / Disagreement

Participants generally agree that both electromagnetic repulsion and degeneracy pressure contribute to the illusion of solidity, but there is no consensus on the relative importance of each effect or how they interact.

Contextual Notes

Some limitations in the discussion include the lack of detailed definitions for degeneracy pressure and its implications in various materials, as well as the absence of a thorough exploration of how these forces operate in different contexts.

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This question may not come in the bracket of quantum mechanics but here's the question-
If most of the atom is empty space what gives the illusion of solidity?
 
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A common answer: electrons repel electrons (EM force)...
A more interesting answer: the electron Degeneracy Pressure.
 


gomunkul51 said:
A common answer: electrons repel electrons (EM force)...
A more interesting answer: the electron Degeneracy Pressure.

Well, I'm not expert on QM, but I think that these are two distinct effects, and that the first one (Coulomb repulsion) is what is responsible for the "illusion of solidity" in everyday objects. Otherwise, how would you explain the solidity of non-degenerate matter?

Please correct me if I am wrong.
 


cepheid said:
Well, I'm not expert on QM, but I think that these are two distinct effects, and that the first one (Coulomb repulsion) is what is responsible for the "illusion of solidity" in everyday objects. Otherwise, how would you explain the solidity of non-degenerate matter?

Please correct me if I am wrong.

You are correct, those are distinct. The first one, as I said, was a common answer given by physicists. The second answer is different but more interesting as it may in fact be what stops materials going through each other. I was mealy pointing the OP to the right direction, where he may find a full answer to his question.

*Degeneracy pressure exist in metals and other materials, they don't have to be "degenerate matter" to be affected by it. What makes the later one exceptional is that degeneracy pressure in the dominant force in that matter.
 


Brian Cox recently hosted a good lecture on Quantum mechanics and covered this quite well I thought.
Here's the lecture, thankfully it was posted on YouTube as it isn't on BBC iPlayer anymore.

http://youtu.be/4f9wcSLs8ZQ

Edit: Also, at one point, it gets very funny with some rude innuendo. What innuendo isn't rude!
 
Last edited:


MartinJH said:
Brian Cox recently hosted a good lecture on Quantum mechanics and covered this quite well I thought.
Here's the lecture, thankfully it was posted on YouTube as it isn't on BBC iPlayer anymore.

http://youtu.be/4f9wcSLs8ZQ

Cool video!
Brian tries to explain elementarily, that the illusion of solidity is caused by electron degeneracy pressure. Option No. 2.
 

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