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Ik zeg het trouwens verkeerd. De uitleg in de docu is dat entanglement zou kunnen betekenen dat er een soort van zero point field bestaat waardoor alles direct met elkaar verbonden is of kan zijn. Dit is een stuk dat van de What the Bleep site komt... Klopt het wat hier staat of worden er fouten gemaakt?
What the bleep is Quantum Entanglement?! I really need to know.
Truly, Jacqui Alexander, Tennessee
Quantum entanglement occurs when two particles, such as two photons, are created from a single source. In laboratories, paired photons are often created by shooting individual photons from a laser through a specifically structured crystal. As the photon passes through the crystal it sometimes divides and becomes two photons operating at a lowered energy frequency than the original photon. The frequency states of the twin photons if added together however, equal the original photons total energy frequency. Nothing is lost in the splitting.
From the moment of their creation, the quantum states of the twin photons are intertwined. (Remember that entanglement happens with all kinds of particles, including electrons. Im just using photons as the example here.) By quantum state I mean the spin state, or polarity of each photon. Although photons dont actually spin on an axis or have a polarized charge, they act as if they did, and spin and polarity are two of the best metaphors humans can come up with to describe the indescribable aspects of particles.
The quantum states of these paired photons will always be the mirror opposite of one another. If the spin of one of the photons is up, then you can bet your last dollar that the spin of its entangled partner will be down.
Now the entanglement part of the situation is this: each of the paired photons apparently affects the quantum state of the other, even over large distances. For example, if you expose one of the photons to a magnet and watch its direction of motion you can tell if its spin up or spin down. The very act of interfering with the one photons direction will affect its partner, which will instantaneously acquire a quantum state opposite to its partners measured quantum state.
This is an example of what Einstein called spooky action at a distance. This was the part of quantum mechanics he refused to believe, because action at a distance violates the theory of special relativity by implying faster-than-light communication between the two particles.
In 1935, Einstein was joined by physicists Boris Podolsky and Nathan Rosen in creating what became known as the EPR paradox, a thought experiment which demonstrates that quantum mechanics predicts action at a distance, thereby violating special relativity and the common sense classical understanding that in physical reality, if you affect one particle over here, it cant affect a particle over there.
In the classical sense of viewing the world, Einstein, Podolsky and Rosen were correct. A tennis instructor putting top spin on a tennis ball on one court wont affect the spin of another tennis ball in play five courts away, even if both balls were originally packed in the same can. But in the quantum world and in quantum mechanics, the laws are apparently different.
In 1964, John Bell showed that quantum mechanics predicts a much stronger statistical correlation between the measurement results performed on different particle spin axes than does something called the hidden variable theories. As it turns out, this prediction of a stronger correlation has been proved to be true. Experiments conducted verify the behavior of particles as predicted by standard quantum mechanics.
Today, the majority of physicists believe the predictions of quantum mechanics. This leaves us, of course, to come up with some sort of explanation of how this seeming action at a distance actually occurs. People who still believe in the old Copenhagen Interpretation believe that collapsing the wave function of a particle through measurement, collapses the wave function of its entangled partner instantaneously. This explanation accepts that in quantum mechanics, the principle of locality is violated. Action at a distance happens. We may not understand how, but it does.
But a lot of physicists still find action at a distance hard to swallow. Hence there are other theories, such as the Many Worlds Theory which says that it is not action at a distance which collapses the wave function of an entangled particle, it is the splitting of the Observers into different histories that actually accounts for it. Another possibility is that in the quantum world, time does not exist in a forward flow. What seems to be action at a distance is actually a communications process between the two particles that goes backwards in time.
No matter how it works, quantum entanglement is actually the basis for some pretty interesting developments technologically. One is Quantum Cryptography, which relies on entanglement as an eavesdropping trace indicator. Another is Quantum Computing, which uses entangled quantum states to perform computations in parallel much more quickly than they could be otherwise conducted.
So there you have it, Jacqui. Hope this helps!
ED NOTE: For what its worth, Ill throw in my own two cents on the matter. Occams Razor states that one should make no more assumptions than necessary when trying to explain something. Following that principle, the simplest explanation Ive run across for action at a distance seems to be the zero point field theory, as described by Lynne McTaggart in her book The Field. If everything all universes and everything in them are connected at the most fundamental level conceivable in an invisible zero point energy field (which takes the place, interestingly enough of the old discredited theories of the ether) then here we have a medium, so to speak, which could account for action at a distance. For in this field all things are connected and at One; there is literally no distance between things, for nothing is separate from anything else.
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