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Another question about photon perspective, concerning entanglement

  1. Apr 9, 2008 #1
    Given the idea that a photon experiences only one 'time-slice' from its perspective, and exists as one elongated unit that stretches from the point of emission to the point of absorption, what implications does this have on ideas of cause and effect?

    I was thinking about the so-called 'spooky actions at a distance' effects of quantum entanglement, the apparent instantaneous communication between an entangled pair despite distance... in seeming violation of C.

    Doesn't the 'time slice' idea of a photon's passage negate traditional ideas of cause and effect in its frame? Is it possible that, from our point of view, the change made to one end of the entangled pair snakes back down the 'tuning fork' of light pathways, to the moment of entanglement, and down the other path, to the other detector... in one exact time-slice, that of the photon? I'm having trouble seeing any holes in this idea, and it doesn't require any weird notions of 'nonlocality' or 'unreality'. It seems like good ol' fashioned Einsteinian hidden variables...

    Too crazy or perfectly sensible?

    It's an idea I had back in high school, but Physics Forums wasn't around then...
  2. jcsd
  3. Apr 9, 2008 #2
    I agree with your idea. Well, kind of... It only makes logical sense that an entity "traveling" (it would only appear to travel in this case) at the speed of light would not age at all - regardless of the distance covered... so the photon's endpoint and starting point are part of one closed entity. This gives rise to the quantum behavior.

    I say "kind of" because the way I see it - if we could take a snapshot of the photon inside it's frame - it wouldn't look like the tuning fork you describe... it would be more like a fuz of every possible path converging only on it's two actual endpoints. In the frame of the photon, it wouldn't look like a tuning fork and the entity only needs to be Planck sized in space-time in that frame. Or if you want to call it a time-slice, that would work too.

    It's something I posted about here years ago as well, and didn't get much feedback from other members (I have been away almost 4 years).

    This diverges from your topic and should be discussed in another thread, but... the whole idea of multiple entagled points of a single photon in a closed space-like envelopment ties in with the idea of an electron's structure in a curved space-time as a stable, sub-femto scale singularity (and so yes, our smallest stable black holes could really be electrons).

  4. Apr 10, 2008 #3
    Well, by 'tuning fork' I meant the one appearance of the two branching pathways of entangled photons, beyond the polarizing filter.

    That's interesting.
  5. Apr 10, 2008 #4
    Well don't everybody chip in at once :)
  6. Apr 11, 2008 #5
    Even if there are hidden variables, which there probably are, the change information still has to travel down the "tuning fork" at a speed greater than light!

    The big question is "what multiple of light-speed does the information travel at?"

    We know light propagates as a transverse electromagnetic wave. Is it possible that entangled photons communicate along the "tuning fork" by way of longitudinal waves?
    In nature longitudinal waves can travel multiples of 10 times faster than transverse waves.

    Einstein's "spooky action at a distance", and quantum theorists' "non-local event" responses, just means they don't have an answer to what's happening.
  7. Apr 11, 2008 #6
    These things do not happen exclusively to photons but in principle they can happen to all elementary particles. Unless one happens to believe that all elementary particles have a speed of light but an effective velocity much lower than the speed of light, e.g they have a Zitterbewegung, the zero interval argument is problematic.
  8. Apr 11, 2008 #7
    My understanding of entanglement is:
    In an EPR experiment two subatomic particles interact and are moved a great distance apart. The particles are correlated so that the action of one affects the behaviour of the other. When measurements are made simultaneously on the separated particles, the results should be independent of each other's quantum state, since they cannot share information, as it would need to travel between them at a speed greater than that of light. Experiments carried out to test this proposal have proven that separated particles remain entangled and do somehow communicate their information at speeds faster than that of light.

    Do they communicate their state by longitudinal waves?
  9. Apr 11, 2008 #8


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    Perhaps I'm a bit irritable today, but I'm formulating a new policy - we'll see how it goes. When I see the words "photon perspective" in a thread, I'm going to make a quick note that a photon doesn't have a perspective, refer people to the previous discussion on the issue, and lock the thread.
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