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Conceptual quantum question

  1. May 26, 2005 #1
    1. Planch's constant[h bar] is really small, so small that in our macroscopic world we generally can't notice it. what if [h bar] were larger, what would our world be like if it were larger? How much larger would it have to be to so that macroscopic objects displayed "quantum behavior'.

    2. how will our world be different if [h bar] were larger?
     
  2. jcsd
  3. May 26, 2005 #2
    Take Heisenberg's uncertainty principle:

    uncertaintyinposition*uncertaintyinmomentum>=h/4pi.

    And try to imagine what could happen.
     
  4. May 27, 2005 #3

    Meir Achuz

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    hbar is only seems small because it is a small number if you use mks units.
    In the same way the Earth is tiny if you use light years.
    If you use atomic units, hbar is of order one.
    Then you get the atomic world of atomic physics.
    If hbar were of order one in mks units, we would be living in the atomic world.
    There are books by George Gamow, "Mr. Thompkins in Wonderland",
    published by Dover, that describe this world.
     
  5. May 27, 2005 #4
    So if hbar were higher then momentums uncertainty will be higher. I understand that, i understand that the world would be different. For example I could walk to the store you can either know where i'm at (positon)or know my momentum never both. would that be the case? It makes sense to me that a 5000 hp car although fast to us is slow compared to maybe a cosmic ray.
     
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