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I'm aware of many ideas people have come up with for this question. I understand why they don't work. However I was thinking about another method involving an array of multiple entangled particles.

Each particle in array one would have an entangled corresponding particle in array two. Each array would have particles divided into groups of 2. With each group of two measure the first one to translate a 1 and the second to translate a 0. Someone far away would have a second array entangled in the same pattern as in the first array and would read the binary code sent. I'm assuming this would not work but am unsure why.

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  • $\begingroup$ What if this works, but someone reads your post and patents your idea under his name? $\endgroup$
    – safesphere
    Commented Jan 29, 2018 at 4:53
  • $\begingroup$ Okay. We've each got three groups of two particles, entangled as you prescribe. You send me a message via the protocol you've devised. I make some pre-arranged measurement on each of my six particles. I measure (0,0), (1,0) and (0,1) for the three pairs. What message should I infer that you sent? $\endgroup$
    – WillO
    Commented Jan 29, 2018 at 5:47
  • $\begingroup$ It’s almost impossible to guarantee perfect correlation of entangled particles in the first place. An array of multiple entangled particles would be if not impossible then impossible to pull it off and recognize it at the same time. $\endgroup$ Commented Jan 29, 2018 at 8:09
  • $\begingroup$ You don't understand why schemes for FTL communication don't work. The reason is that quantum physics is entirely local physics.stackexchange.com/questions/374533/… $\endgroup$
    – alanf
    Commented Jan 29, 2018 at 9:41

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The reason why one cannot do faster than light communication using quantum entanglement is not because we have not been clever enough to come up with a scheme that would work. It is a fundamental aspect of quantum entanglement.

It is often said to be difficult to understand how quantum mechanics works and often some famous physicists are quoted to say that nobody understands quantum mechanics. Part of the problem is that the interpretation is, well, open to interpretation. However, there is a bit of a trick that one can use to help one to figure out how particular situations in quantum mechanics would work. Just pick one particular interpretation that is fairly simply to understand and work it out in terms of that interpretation. It doesn't have to be one that you believe is true. Since no one has so far figured out how to observe physical differences based on these interpretations, all these interpretations will produce exactly the same physical results.

One interpretation that is quite simple to use for this purpose is the many world interpretation, because it does not include collapse. Using this interpretation, one can quickly see that no quantum entanglement scenario can ever produce faster than light communication. Quantum entanglement implies different worlds, each having particular states associated with the different partites that are entangled. When you observe a particular state for a particular partite, then it simply means that you are restricting yourself on one of the worlds and then the state of all the other partites, regardless of how far away they are, are fixed to be the states they would have on that particular world. No faster than light communication is required.

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