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ste
03-20-2008, 03:57 AM
I was reading up on quantum entanglement and noted it to be said that no information could be transferred faster than the speed of light between a set of entangled states.

I am curious to know the justification of this statement, other than taking for granted special relativity's assumption that nothing can travel faster than the speed of light (and that the speed of light is constant).

Epsilon=One
03-20-2008, 04:02 AM
I was reading up on quantum entanglement and noted it to be said that no information could be transferred faster than the speed of light between a set of entangled states.

I am curious to know the justification of this statement, other than taking for granted special relativity's assumption that nothing can travel faster than the speed of light (and that the speed of light is constant).There is no justification. It is obviously incorrect. Just look about; or consider what is known of quantum mechanics and the motion of the Cosmos.

Philomath
07-02-2008, 07:56 PM
There is no justification. It is obviously incorrect. Just look about; or consider what is known of quantum mechanics and the motion of the Cosmos.

Can you name some specific examples of faster-than-light information travel?


Actually, the reason is that information cannot be communicated using entanglement. Essentially the way it works is that two particles are entangled such that, for example, the sum of their states is 1. If you measure the state of the first particle to be .2, for example, then the other particle MUST be .8 in this example. But the way quantum states work, nothing can affect these particles in order for them to remain entangled. In other words, the entanglement 'breaks' if the particles are tampered with.

I apologize since my knowledge of this area is not the best, but from what I've read, my example should be a fairly clear illustration of how it works (I hope).