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Smallest unit of matter

  1. Dec 3, 2009 #1
    Does the smallest unit of matter have depth, or any quantity of space? My theory is that if a unit has space, it can still be divided in half. So what is the smallest unit of matter, one that cannot be divided in half?
  2. jcsd
  3. Dec 4, 2009 #2
    Have you heard of atoms?...
  4. Dec 4, 2009 #3


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    Elementary particles, according to standard QM are point-like objects (with no spatial displacement), and according to string theory are string-like objects (1-D strings, weird stuff...).
  5. Dec 4, 2009 #4
    As noted above, in the standard model of particle physics, particles are modeled as idealized point like objects without size.

    This could possibly be true if space is really continuous as assumed in relativity....however such an assumption leads to infinites, divergences (inconsistences) between relativity and quantum mechanics...so we know something is not quite right with this idea as currently formulated.

    You can read about Planck scale physics: you will find that below some minimum length/area/or volume, such as about 10-33 cm length, things cannot be further divided because quantum froth (uncertainty) may take hold...everything becomes jumbled in energetic undulations....... time/space/matter as we know it becomes quantum foam...and these distinct entities as we know them on large scales become energetic uncertainties...akin, perhaps, to Heisenberg uncertainty.....

    An analogy to this minimum size at Planck scale in string theory is called "T duality" where, as a string radius is decreased in one model, it is the same as increasing the radius in another string model....so again there appears to be some minimums which nature may dictate.

    But there is no absolute incontavertible experimental proof to any of the above explanations.
  6. Dec 4, 2009 #5
    Atoms are the best smallest parts of matter, especially those of noble gases.

    Each division takes some energy. When you divide many noble gas atoms in groups, it takes little energy. As soon as you try to divide a single atom in parts, it takes much more energy. And the divided parts - charges - are very sticky. If not allowed to recombine in a neutral atom, they merge with matter very easily. Impossible to get rid of. Some think they are point-like. I say they are long-handed.
    Last edited: Dec 4, 2009
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