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Quantum mechnics

  1. Feb 23, 2006 #1
    I don't know much about quantum physics but i know that, that we cannot predict a result of any action according to quantum mechanics but we can that there is a probability for every result
    Then for example,if i keep my hands ina way that my palms are touching the wall and if i start pushing the wall then is it possible that there is a probabilty for me to pass right trough the wall????????
  2. jcsd
  3. Feb 23, 2006 #2
    No that won't happen, unless you push hard enough to break through. It is possible to know the momentum and speed of a car simultaneously. The problem is doing the same with smaller particles with the boxing gloves we have today. This does not mean that you can suddenly turn into a werewolf or a dog "just because of quantum mechanics" :yuck:
  4. Feb 23, 2006 #3
    Actually, the probability of walking through a wall in somewhere is the order of 10^-34

    sorry I can't find the source for this one.

    But I'd say it is 0
  5. Feb 23, 2006 #4
    The uncertainty principle has nothing to do with the bluntness of our experimental equipment, but rather it is a fundamental aspect of nature.
  6. Feb 23, 2006 #5
    There is actually a probability that you will go through the wall but like waht said its very very small if say the flash hit himself at the wall as fast as he could for the entire age of the universe he still wouldnt have gotten through it yet. it isnt 0 it is extremely close to 0 so its possible
  7. Feb 24, 2006 #6

    Tom Mattson

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    I suppose you meant that it is possible to know the momentum and position of a car simultanesously. Well, you can, but the question is to what degree of accuracy can you know each? As has been noted already, both variables cannot be known with arbitrary accuracy and this fact has nothing to do with our measuring instruments.
  8. Feb 24, 2006 #7
    Of course you can pass your hand through the wall! My Quantum professor said if we could quantum tunnel through the wall into the final we would automatically get an A! He wouldn't have lied to us, would he? ;)

    Of course, I was black and blue from bouncing between two walls... I still got my A, though. :)

  9. Feb 24, 2006 #8
    I'd bet the probability of winding up embedded half in/half out of the wall is greater than tunneling all the way through with it, so don't try this at home! :)
  10. Feb 27, 2006 #9
    In classical mechanics, we establish the relationship b/w the physical quantities like position, velocity.
    But in QM, we establish the relationship b/w the probabilities of different phsical quantities.
    Acc. to QM(Feynman), the light is reflected at all the angles and not only at the angle equal to the angle of incidence, but the probability is maximum for this angle.
    Quantum mechanically, u can tunnel thru the wall(try it :) )but the probability tends to zero.
  11. Feb 27, 2006 #10
    I would think that the probability grows exponentially with your mass, the density of the wall and the thickness off the wall. If you could alter the states of all of components of all of the atoms in your body into phase with the wall, then it would be possible. Otherwise the probability of being stopped by the wall would be nearly infinite.
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