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Simple quantum entanglement qustion

  1. Jul 3, 2013 #1
    i do not posses deep knowledge of Quantum physics nor regular physics for that mater novice at best. so i have a idea say you have 2 entangled particles separated by say 5 light years by the idea when you observe them you will get result X and the opposite on the second particle so Y. soo if you set a light bulb to go off if the result from observing the entangled particle is X, and if both sides separated by 5 light years observe the particles and side A gets Y then side B will automatically get X and the light bulb will go off resulting is side A knowing the bulb went off so wouldn't that mean information traveled faster then light. sorry for the confusion
  2. jcsd
  3. Jul 3, 2013 #2


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    Staff: Mentor

    You can know that the light bulb is off, but you did not transmit information with that - you just followed instructions decided in advance. Try to send an email with that method - it cannot work.
  4. Jul 3, 2013 #3
    but the results from observing the particle can go in 1 of 2 ways so you cant know ether the light bulb is off or not until you observe the particles resulting in you gaining knowledge what is on the other side of the 5 light year distance
  5. Jul 3, 2013 #4


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    There has been some previous discussion of this idea - try this thread: https://www.physicsforums.com/showthread.php?t=675398&highlight=Entanglement and look for the replies from the science advisors.
  6. Jul 3, 2013 #5


    Staff: Mentor

    In order to send information you need control of whats at the sending end. When you observe one particle at the sending end its 50-50 what it is - you have no idea what it is. The other end its the opposite but since the sender had no idea what it was the receiver cant infer anything from it.

    Some bright spark came up with a way around it by cloning a particle. It led to the development of the no cloning theorem - so you cant do it - at least that way:

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