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Comment by gambiting | Hacker News Reader

Question. How is this any different to writing A on one piece of paper, then B on another piece of paper, and selecting one randomly, then giving the other piece to someone else. Then the other person travels a light year away from us, and we both look at our pieces of paper simultaneously, at pre-agreed time. If mine says "A" then I know the other one says "B", and vice-versa. I instantly know the state of something that is a light year away, even though no information was actually transmitted. Isn't this how quantum entanglement works in principle?

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The whole point of the Bell experiment is that it proves that which one has the "A" and which one the "B" wasn't pre-decided when the pieces of paper were separated.

>Isn't this how quantum entanglement works in principle?

Not it's not which is what makes the whole thing interesting. The whole point of Bell's Theorem and the experiments is to demonstrate that that hypothesis doesn't work.

This is a good question! It's different because if you pass quantum entangled information to the other person, you will be able to cooperate more effectively with them on certain games using that information. It's explained very well in the second paragraph of this article: http://www.scottaaronson.com/blog/?p=2464 .

In a simplified way, this is what Bell's theorem tells you: That quantum informations behaves fundamentally different than "precalculated" random information.

I'm missing the part where it is explained how they cooperate better in the 3rd and 4th paragraph. Especially since sharing independent bits of equal probability 0 and 1 isn't comparable to sharing entangled qubits (at least it isn't explained how they are equal).

You might like this explanation: http://www.scottaaronson.com/blog/?p=2464

It discusses that 'conspiracy' and explains why it can't happen.

In a sense 'maybe not'. This would violate the bell test anyways as you predetermine the outcome by writing it down. Someone already knows what is on the paper. This is thus also subluminal communication as the outcome was already determined at the start (assuming you traveled at subluminal velocities). The idea of the entanglement states that the spin of the electrons is determined at the same time which guarantees their connection, not the outcome of the spin.

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