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Not so uncertain principle

  1. May 28, 2005 #1
    I thought of this the same time i was thinking of my other post (a.k.a. If God does exist).

    we cannot tell where the electron is by testing it, but we can tell where it is not. If we shoot particle form point A, and it does not return to point A, we can tell that the electorn is not in the orbit that would have existed by a straight head on collision with the particle. Using this method and many super computers, in theory could not we limit the posible positions, speeds and directions of the electron, and given ehough time we could actualy leave only one posible path. This might even be applied to atoms above H, given though the time and amount of calculations would grow (expotetionaly so).
  2. jcsd
  3. May 29, 2005 #2


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    You seem to have missed the whole point of the "uncertainty" principle. The "uncertainty" principle doesn't say you can't know the electron's position- it says you can't know the electron's position and momentum at the same time. If you don't know the position of an electron, you can't be sure that some of your particles won't hit the electron. As soon as that happens, you have changed the electrons momentum.
  4. Jun 4, 2005 #3
    maybe i did not state like i meant. I do know of the uncertainty principle, which says the better you know the position or momentum, the worse you know the other. What I am saying is there might be some long drawn out way to eliminate posible postions and momentums. The main problem is how much calculating it would take even knowing an electrons position and momentum, to predict the continuation of its orbit for even a year. Now multiply this by all the orbits we can prove false, and we cannot not find a computer to handle this.
  5. Jun 4, 2005 #4


    The uncertainty principle is a real physical property of matter, not just a limitation on measurement. If it wasn't, the sun would never have been able to attain fusion. (it would have to be about a thousand times hotter in the core). You can't try to get around the unceraitnty principle like that because it is a physical property of matter.
  6. Jun 5, 2005 #5


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    Yes, it is clear that you do not understand what the "uncertainty principle" says. Every time you do one measurement (in order to "eliminate posible postions and momentums") you completely change the situation. The next measurement cannot be used with preceding measurements to get a more accurate result- the preceding measurements are no longer valid and you are right back to the original situation with only one measurement.
  7. Jun 5, 2005 #6
    ok, my misunderstanting. But if one could time travle, could not one go back and do a different expereiments on the atom at the exact time, and come up with the answer after enough test were done.

    If this is true, then would not time travle make the uncertainty principle not true. Which would only allow on or the other to exist. Just another problem with time travle
  8. Jun 6, 2005 #7
    Do electrons really come in and out of existence?

    The motion of the electron about the nucleus is a somewhat controversial topic. The electron does not exhibit motion in the physical sense — it does not "float"; rather, it seems to appear in and out of existence, at various points around the nucleus (of course, 90% of the time the electron can be found in its designated orbital). A simple analogy would be a firefly, in a dark room, lighting up at various points about a central light source — it can light up anywhere, but it is most likely to appear closer to the source than otherwise.
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