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B Can a particle exist without time

  1. Aug 24, 2015 #1
    I was wondering about entangled particles or particles with superposition being able to communicate nonlocally, and then thought about space and time. I know Einstein says that space and time are one in the same called spacetime. He also states that something that travels the speed of light doesn't experience time, but it still propagates through time having to move through space too. Now when you observe an entangled particle if one is up the other is down instantly. Then when you're not looking at it the particles have superposition being able to be both up and down at any given moment it is not being observed. The fact that a particle can act infinitely faster than the speed of light in a vacuum makes me think that an entangled particle exists within our perception of space but not time. I know I may be wrong, but any insight would be much appreciated, thank you.
     
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  3. Aug 24, 2015 #2

    bhobba

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    That's not what entanglement or superposition implies. Its simply a correlation - that's it - that's all. We have interpretations where it's more than that - but that's all they are - interpretations.

    Time is a part of all our currently accepted theories.

    Your view of light is a common misconception:
    https://www.physicsforums.com/threads/photon-elapsed-time-equation.774176/

    Thanks
    Bill
     
    Last edited: Aug 24, 2015
  4. Aug 24, 2015 #3

    ZapperZ

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    I have a glob that has no initial momentum. At time t=0, it spontaneously splits into two, daughters A and B, and they move in opposite direction to each other, with no other external interaction. At some time later, when A is very far away from B, I measure the linear momentum of A. IMMEDIATELY, I know the momentum of B at that very instant, simply by applying conservation of momentum that we all learn in high school. In fact, if at the same time someone else measures the linear momentum of B, I could have easily tell that person what B's momentum is.

    Now, did this imply that the particles "can act infinitely faster than the speed of light in vacuum"?

    Zz.
     
    Last edited: Aug 24, 2015
  5. Aug 24, 2015 #4
    Well thats interesting from a philosophical point of view.
     
  6. Aug 24, 2015 #5

    ZapperZ

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    How is this interesting "from a philosophical point of view", and is this really surprising, considering that this was never an issue when we were dealing with classical mechanics?

    Zz.
     
  7. Aug 24, 2015 #6
    Knowing the forum rules I'm hesitating to answer. Let's just say I've read somewhere that the hidden non-local variable might have something to do with our brains (call it knowledge, consciousness, free will ......)
     
  8. Aug 24, 2015 #7

    ZapperZ

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    Yikes!

    The example I gave is a standard classical mechanics scenario that we present in high school and intro college physics! There are no "hidden non-local variables" there! Are you telling me that when you encounter a conservation of momentum problem in your first year physics class, you automatically think of such hidden variables? Really?!

    Zz.
     
  9. Aug 24, 2015 #8
    To me, this is a fascinating question, nevertheless, i think perhaps one needs to define what is meant by the terms particle, time and exist. Additionally,
    all these things seem to be dependent upon our "laws of physics". It is possible to make up different laws, that would have different variables but could
    essentially have the same behavior. (consider, for example, Heisenberg's Matrix mechanics, and Schrodinger[s wave equation. Additionally Dirac said that
    the only important thing (about a view of a theory) is the mathematics involved. -- he meant that one could call the wave function applying to charge, and later
    it became probability density, but it continued, because the inherent mathematics of the structure remained (the Schroedinger wave eqn. stayed with the same structure.
    so one must not be caught up in names. Which is why the terms you use, could need to be defined(i think), and then one might be better able to answer your question.
    Still, i think it is a good one.. (things in the early universe act a LOT different than are dreamed of "in your philosophy".
     
  10. Aug 24, 2015 #9

    Nugatory

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    You've almost certainly misunderstood what you've read. The primary motivation for the (futile, we now understand) search for a realistic non-local hidden variable theory was to put QM on the same solid ground as classical mechanics: get rid of the measurement problem, get rid of superluminal influences at a distance, and especially to get rid of any requirement for conscious observer.
     
  11. Aug 24, 2015 #10
    Wished to have added... that in the early universe (before and during inflation, things were very, very different, and cannot be any comparison, between
    then and now).. Afterwards, things settled down, and now some meaning may exist (but not for whole universe, at all times).
     
  12. Aug 24, 2015 #11

    Nugatory

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    We're drifting very far from OP's question here, which has been pretty much answered by Bhobba and ZapperZ.
    I'm going to close this thread now, although as always, if you have more to add to thread PM me so that I can reopen it for your comment.
     
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