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A thought experiment (excuse me if I have wrong information, i'm new)

  1. Jul 8, 2012 #1
    So, let's think of a world where all the decisions are made by probability, e.g. flipping a coin, and quantum physics was never discovered.

    Now, let's say they use a device, a contained version of the double slit experiment, except that the particles are supposed to land in one of two different "rooms" that are exactly the same - that won't happen, of course. They always open the right room, so that if the particle is there it won't be in the other room, and so on. Now, as we know, the particle will be in a superposition of states, in both rooms at the same time, until observed. But since the only open the right room, and therefore only observe the particle in the right room, so in this way can we directly control probability?

    Again, sorry if my information is wrong. I'm new.
  2. jcsd
  3. Jul 8, 2012 #2


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    Half the time you open the door to the right room, there will be a particle in it. The other half the time, there will be no particle. Just as probability and (QM) predicts.
  4. Jul 8, 2012 #3
    Can you explain why though?
  5. Jul 9, 2012 #4
    It can't be explained. It's just the way QM works.
  6. Jul 9, 2012 #5
    I get it if you randomly observe it, but is it possible to willfully choose which one is observed, and therefore control randomness? Or should I stop typing half asleep?
  7. Jul 9, 2012 #6
    According to our current understanding of the universe, no. You cannot willfully control the probability of measuring a certain outcome
  8. Jul 9, 2012 #7


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    No one "randomly observed it". You looked in the right room every time. You can't control what you observe or don't observe when you look.
  9. Jul 9, 2012 #8
    I didn't mean if you randomly open either room, I was talking about opening it at a random time.
    I some what understand now.
  10. Jul 9, 2012 #9
    replace "until observed" with "until a select category of interaction happens"

    it does not have to be any (human/live/life) observation.
  11. Jul 9, 2012 #10
    the coin will not always land up in the room you happen/choose to open.

    there is only a 50% chance that the coin will land up in the room you choose to open, no matter how random the action (of picking one of the rooms is)

    we are not pre-determined to choose the "right/correct/coin" door....

    so in a double-slit experiment, if you put a camera on one slit....the camera will not always record the passage of the photon through that slit, it will record it only 50% of the time (...it might be lower due to environment/em noise)
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