pondělí 27. dubna 2009

AWT and mechanical models of entanglement

By AWT explanation of quantum entanglement is closely related to wave function collapse. Try to imagine, you're a sailor, who is staying at night on the end of floating wharf, to which some boat is attached. Because night sea is stormy, everything (both sailor, wharf and boat) are wobbling up and down, but in different phases. From the perspective of sailor this boat sways randomly.

The observation of quantum particle is analogous to situation, when sailor touches the boat for a moment, thus exchanging some kinetic energy with it. What will happen, after then? The wharf and boat will begin to oscillate at phase. It means, the sailor will keep his relative position with respect to boat, so he cannot detect any boat wobbling anymore, because he moves by the same way. We can say, the wave motion/function of boat has collapsed from local perspective of that sailor. It still remains undulating from perspective of another observer, though - this is the moment, when relativity takes place in quantum mechanics.

In AWT both particles of observer, both particles of observed object are formed by dense nested clusters of another undulating particles, recursively. At the moment, when observed object exchanges some energy with particles of observer during process of observation, the undulations of both systems aren't independent anymore: their internal fluctuations will undulate at phase, too. Briefly speaking, the observer will get entangled with the particle observed. As the particle doesn't undulate independently from this moment, the corresponding part of their mutual undulations will disappear from observation, because the internal motion of both systems has been synchronized.

This is what we are calling a collapse of wave function during process of observation. The observer and object are now undulating like single body - the common center of mass of both objects is forming a private reference frame, a sort of independent island of reality inside of wave ocean - from this idea the concept of many worlds follows. This state isn't permanent, indeed - due the omnipresent random undulations of environment a process called quantum decoherence will take place, thus breaking the entanglement state and synchronization of observer and observed object.

A more close and natural mechanical analogy of entanglement can be demonstrated for undulating droplets levitating in low gravity conditions (i.e. oil droplets inside of lava lamp or water droplets under diamagnetic levitation, for example). When we split such undulating droplet into two halves by thin wire, the resulting parts will remain undulate at phase with respect to the center of their common mass. The smaller droplets will therefore "remember" the state of original droplet in certain extent, so they can serve as a quabit memory. Such pair will create their own "inertial reference frame" and/or "local universe" by many worlds interpretation. But as we can see - nothing "spooky" is on such entanglement, in fact.

Note that even though we can combine the different droplet pairs with the same surface amplitude or even frequency, such reconnection will not restore the surface wave of original droplet, until the phase of the surface waves of both droplets will not remain exactly the same - from this the quantum cryptography follows. We can see, while this model is very trivial and natural, only common disbelief in Aether models prohibited scientists to consider it a long time ago in explanation of various quantum mechanics phenomena.

3 komentáře:

  1. While this analogy is quite interesting it is not complete.

    Consider an electron which can have spin up or down and two measuring apparatuses which measure the spin along the same axis. The apparatuses are separated by a distance of a few meters.

    After the first apparatus measures the spin of the particle we have a collapse and up to this point your analogy holds, however the electron flies on to the second apparatus and when it is measured again we cannot detect any superposition, the electron will have the same state we measured in the first apparatus even though it did not have the opportunity to come in sync (to synchronize it's phase) with the second apparatus.

    To save the analogy you would have to claim that as the first apparatus exchanges energy with the electron the second one also somehow gets in phase. But we could set up many such apparatuses one after another and they would all have to get in sync with electron the moment the first apparatus makes the observation.

    Even more problematic is the case with two entangled particles. Imagine that we double the setup mentioned above and we have two entangled electrons flying in the opposite directions. The moment one of the pair of electrons gets measured the second one would somehow have to get in sync even though it didn't exchange energy with anything.

    This is just to show that this analogy although nice does not hold in all cases.

    BTW I have my own crackpot theory which explains entanglement and all the rest :P, it even resembles AWT slightly - everything results from deformations of a 4D spacetime, I will try to publish it within the next two years (I'm serious), internet is full of us crackpots lol

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  2. /*..everything results from deformations of a 4D spacetime..*/ In AWT everything is density gradient of Aether, which can be considered as a deformation of underlying space-time, too. But AWT doesn't assume any particular number of dimensions of that space-time. The number of space dimensions follows from packing of 3D hyperspheres, by which these gradients can be approximated.

    Of course, the higher number of postulates and ad-hoced constants you'll introduce into your theory, the better such theory would describe this particular situation - the less general it will remain at the case of another situations, though. It's tic-for-tat: here's not general criterion, which theory is better in general situation. I'm just following as general way, as possible.

    OdpovědětVymazat
  3. /*..we could set up many such apparatuses one after another and they would all have to get in sync with electron..*/

    This situation corresponds the electron, which gets spin-oriented after passing through magnetic field in Mosbauer experiment. We can prepare spin separated electrons by magnetic field in Mosbauer experiment - even though by quantum principle every attempt to localize electron would lead to violation of spin state and vice-versa. But because the path/momentum of every electron is modified just very slightly/temporarily during passing of electron from one part of apparatus into another - we can still achieve a complete separation of electrons by their spin. This is a principle of so called "weak measurement", because every localized state in QM is just a superposition of many other states in nested Hilbert space - so you can never get a "complete" entanglement or decoherence of particle and observer, until the observer object becomes a part of observer (their mutual space-time distance is what prohibits a full entanglement).

    In my opinion, main problem of boat-sailor analogy is rather an apparent absence of quantization. Whereas water droplets can undulate in standing waves, the quantization of energy transfer can still take place in second example. After all - if you don't believe in boats and droplets, here are experiments, which are confirming this model directly.

    http://www.physorg.com/news78650511.html

    As we can see, even simple model of water droplets can cover the entanglement, collapse of wave function, decoherence and quantum cryptography and seamlessly reconcile Copenhagen and many worlds interpretations of quantum mechanics in few sentences.

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