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A question about quarks

  1. Aug 31, 2004 #1
    the way i understand quarks is that they have mass, yet no physical extensions of any kind. how is this possible?
  2. jcsd
  3. Aug 31, 2004 #2
    Could you expound on that a bit....please.
  4. Aug 31, 2004 #3


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    Subatomic particles are not like billiard balls. All particles display wavelike properties, and do not have crisply defined edges like billiard balls. They do not really have a "size" in the normal sense of the word. You can specify that a quark in a specific state is within a certain volume 99% of the time, and use that volume as a sort of "statistical size," but microscopic particles simply do not have the macroscopic characteristic of "size."

    - Warren
  5. Sep 1, 2004 #4
    another of the more intriguing aspects of the illusion we call reality. electrons and quarks, the fundamental building blocks of all matter, are point particles and have no volume. dont you find that profoundly amusing and stupefying at the same time?
  6. Sep 1, 2004 #5


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    No, what is more "stupefying" is to be able to say they have a volume when we have no ability to determine such a thing. So you would rather we lie?

    By saying something is a "point" particle implies that either (i) the physical real-space volume they occupy is not a significant property of that particle that influences its property; (ii) it is miniscule enough that we can't measure them; and (iii) the concept of "volume" may be invalid when things get to THAT scale.

    These are the "reality" and restrictions that physics are faced with. Rather than make things up just to satisfy someone's "taste" and preference on what reality should be, we abide by what we can, or cannot, measure.

  7. Sep 2, 2004 #6


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    I answered a question about the size of a photon about a week ago. What I said then is true for quarks too, so I recommend that you read this.
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