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Is EVERTHING entangled?

  1. Nov 27, 2008 #1
    Given the hypothesis that everything that exists came from an original singularity, would it not follow, in physics, that everything is "entangled"?

    I don't know, maybe I'm way-off here, but somehow it seems plausible.
     
  2. jcsd
  3. Nov 27, 2008 #2

    ZapperZ

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    If this is true, then entanglement phenomena would be so obvious that they would no longer be 'exotic' and that hard to show. But they ARE exotic and they ARE hard to show. So what does that mean?

    It means that entangled properties are difficult to maintain coherently. Just because something started out being entangled doesn't mean that such a thing can be easily maintained. Long-distance entanglement right now can only be maintained by photons. Using particles are more restricted, both in time and distance, because such coherence are destroyed way too easily.

    Zz.
     
  4. Nov 27, 2008 #3
    I appreciate your comment, Zapper; how you explained it makes this more clear to me.
     
  5. Nov 28, 2008 #4
    I don't agree with this argument. First, entanglement appears pretty much in every chemical reaction, ionization, breaking of molecular bonds, etc. so it's not at all rare or "exotic". The fact that experiments showing correlations of entangled particles are difficult to do is irrelevant. Demonstrating gravitational interaction between two iron balls is also hard to do but this doesn't mean that such interaction is "exotic" or rare. It's also hard to "see" quarks but they are no less common than electrons.

    Those particles that interact with other particles from the environment become entangled with those. As the system becomes more and more complex, the experimental results cannot be interpreted in any meaningful way because of our lack of knowledge regarding the new, complex, system and computation limitation. However, this does not mean that entanglement disappears.
     
  6. Nov 28, 2008 #5

    ZapperZ

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    But our "realization" of it is, i.e. we don't normally see such chemical reaction on the human scale that we identify as "entanglement". If it is, then we would see it easily and identify with it. Yet, we STILL consider quantum behavior as the behavior at the small scale, not the classical scale.

    It has been shown that even ONE single interaction can destroy the coherence of a single-particle state. While that interaction results in a 2-particle state, it still has change the original state whereby the original single-particle coherent state has been destroyed.

    The fact that we do not see, at the classical scale, all the quantum phenomena (and I deal with superconductivity, which Carver Mead claims is the clearest manifestation of quantum effects at the macroscopic scale), clearly shows that you can't simply carry those across from one scale to the next. You and I still do not know if the differences between the classical and quantum realms are simply separated by a crossover, or a "phase transition".

    Zz.
     
  7. Nov 28, 2008 #6
    I,too, don't entirely agree with zapper. But entanglement does appear to be subtle.

    While tehnically, correct, you don't EVER (no never) want to simply set aside a "thought nugget" because conventional physics hasn't gotten there yet. Zapper points out shortcomings based on current understanding....And those are legitimate insofar as they go.

    The real issue is whether you believe your idea enough to find alternative explanations and experimental ways of verifying your idea...then you can claim Zapper and I were "shortsighted and myopic" in our thinking!!! The problem is focusing on those key thought experiments that lead to new solutions, not easy to do.

    Roger Penrose has been working alrgely alone for many YEARS on twister theory and still can't get it completed.... If Einstein, also largely on his own theoretically, had not cast aside fixed space and fixed time which "everybody" knows was 'correct", special relativity would have been delayed.

    I did some research on my own with 50 or 60 widely accepted conventional theories: ultimately all proved short sighted and most incorrect: the earth is flat, the earth is the center of the universe, orbits are circular, the universe is our galaxy, the universe is static, black holes are fictituous (these last two wrong ideas even sucked in Einstein) alchemy, atoms don't exist, there is an aether, there is man made global warming,etc,etc,etc

    Let me offer an interesting alternative hypothesis: telepathy is due to entanglement! Unproven of course, but tantalizing!!! (not my idea, by the way)

    And take your idea one step further: if our universe came from a random singularity then so did an infinite number of others...so not only is entangelment possible in our universe, maybe there is "entanglement" among all universes! Crazy, maybe, but if you consider a related hypothesis that gravity leaks to other dimensions...why not other universes....maybe via nearby branes that we are unable to detect (yet another hypothesis)...
     
  8. Nov 28, 2008 #7

    Fredrik

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    I was hoping that you were joking at first, but you seem to be serious. Anthropogenic global warming has definitely not been proved to be either of those things (shortsighted or incorrect), so you shouldn't be claiming that it has in a science forum.
     
  9. Nov 28, 2008 #8

    Doc Al

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    Alternative to what? Before you worry about "explaining" telepathy (using entanglement, no less), first you must demonstrate that it even exists.
     
  10. Nov 28, 2008 #9
    Telepathy is a stretch, in my book, but the discussion that went with it was interesting....
    don't recall where I read it...

    Entanglement, I thought, was generally accepted today, but is it rigorously verified...I don't know. ..but I don't plan on doing experiments anytime soon .

    Brian Greene, for example, in Fabric of the Cosmos cites work by EPR, Bohm, Bell and Aspect and concludes:

     
  11. Nov 28, 2008 #10
    Perhaps, hadn't thought of it that way... yet, you make it sound as if it's a proven scientific reality: Should you be claiming such in a science forum...??
     
  12. Nov 28, 2008 #11

    ZapperZ

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    Then you shouldn't even have brought it up. Explaining telepathy using quantum entanglement is a bastardization of QM. It is also crackpottery, which will NOT get you very far here in this forum if you've read the Guidelines.

    I strongly suggest you halt this line of discussion.

    Zz.
     
  13. Nov 28, 2008 #12

    Fredrik

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    I didn't make that claim. It was you who claimed the opposite. I don't have the expertise to vouch for it personally, but it's clear that the evidence has convinced a vast majority of those who actually do research in that area. In my opinion that means that it's not inappropriate to say that AGW is real in a science forum. (It is however inappropriate to discuss this in a thread about entanglement in the quantum physics forum, so this will be my last post about this).
     
  14. Nov 29, 2008 #13
    Sure, quantum effects are not obvious at macro scale and I didn't say they are. What I want to point out is that this is not a valid argument against all particles in the universe being entangled.

    Yeah, but if the system is the whole universe there is nothing that could alter its state, right?

    I think that the classical world is a quantum world. We do not realize this because a macroscopic object is too complex to be described in terms of its constituent particles. So, we use statistics, and by doing so, we loose the interesting stuff.
     
  15. Nov 29, 2008 #14

    ZapperZ

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    A "valid argument" is one that is supported by experimental evidence. You have none.

    Simply claiming that the whole universe is entangled says nothing when you cannot show that. I'm sticking my left leg out. Show me the effect of that via entanglement. And no, I'm not being silly, because this IS the type of effects that we are asking for at the classical scale.

    What state of the universe? You can actually write the quantum state of the whole universe? I'd like to see it please.

    And why wouldn't it change? The entropy state can certainly very well change!

    You don't know that, and at this stage, that is pure speculation. If we are speculating, then my speculation is as valid as yours. So what are we left with? Arguing about our favorite color?

    Zz.
     
  16. Nov 29, 2008 #15
    There is nothing "outside" the universe.
    If we decide that the universe started in one state, it must have spontaneously de-cohered and/or interacted with its self.
    Because quantum states don't act like this (that I know of), I don't suppose the universe could have started out as a quantum state.
     
  17. Nov 29, 2008 #16
    Can you refer me to a text that explains this?
     
  18. Nov 29, 2008 #17

    ZapperZ

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    Er.. any text on Thermodynamics?

    Zz.
     
  19. Nov 29, 2008 #18
    I feel like a retard.
     
  20. Nov 29, 2008 #19
    I wonder if gravity might be a form of entanglement. For all the trying, no one has detected the gravity wave or gravity particle, and if it was instantaneous, instead of propagating at velocity 'c' that could explain orbital mechanics more accurately.
     
  21. Nov 29, 2008 #20

    Hurkyl

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    Please don't clutter up thread with rampant speculation.
     
  22. Nov 29, 2008 #21

    Hurkyl

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    I've seen you argue this before ZZ, but I've never really felt enlightened by your arguments. Maybe a historical analogy would help -- at what point in its development would you have considered the kinetic theory of gas to be credible? At what point would you have considered it favored above the alternatives? (Did it really have any credible alternatives?)

    Now back to this one. What would have to happen before you consider "classical mechanics as an emergent property of unitary evolution, via decoherence" to be a credible theory of classical systems? What has to happen to consider it favored above the credible alternatives? Does it even have credible alternatives? If not, what about favoring it above its (noncredible) alternatives?
     
  23. Nov 29, 2008 #22
    Are you talking about This thread? The one which starts with the question “Is everything entangled”? And then it goes on to develop the idea of telepathy as a form of entanglement. And I am “cluttering” it up by mentioning gravity? A bit pompous on your part, don’t you think?
     
  24. Nov 29, 2008 #23

    Hurkyl

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    The presense of other clutter in this thread does not excuse your crackpottery. That post on telepathy was also inappropriate. (And, if you look, has already been decried)

    However, "is everything entangled?" is actually mainstream science, being a question prompted by the behavior of unitary evolution (which, of course, is backed by oodles of experimental evidence).
     
  25. Nov 29, 2008 #24

    vanesch

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    Should I stay or should I go ?

    If I stay it will be trouble ...

    If I go it will be double...

    :cool: :tongue2:

    Here we go again. Entanglement is a theoretical concept in quantum theory. Now, according to your favorite interpretation, and hence to your favorite "resolution" of the measurement problem, a measurement results in "irreversible entanglement" if you are of the unitary evolution crowd (the MWIers and so on), or results in "breaking up of entanglement" if you are of the projection crowd (Copenhagen etc...).

    But both have the same observable consequences: quantum interference (the difference between the pure state and the mixture descriptions) disappear.
     
  26. Nov 29, 2008 #25

    ZapperZ

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    I don't know what "historical analogy" would have anything to do with this.

    I'm a simple-minded experimentalist, not a historian. Maybe that's why the only thing I can "understand" is an experimental demonstration of what people are trying to sell. So if one is trying to sell that "entanglement is everywhere", then demonstrate to me that that entanglement is everywhere. It is THAT simple.

    So far, I've shown why entanglement is NOT everywhere. I'll stand on my head, and see if someone else who's "entangle" with me would have the urge to want to assume the appropriate position.

    That makes it even more of MY point. If classical mechanics is an "emergent property of unitary evolution, via decoherence", then by the definition of emergent property (per Laughlin and Anderson), then one CANNOT, in principle, derive classical behavior out of quantum theory. Period! More Is Different!

    Zz.
     
    Last edited: Nov 29, 2008
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