3 ms·
A second remark: > Whichever he chooses, the color will be the same as that on the corresponding side of the full-size coin that Alice inserted into Vending Ma
by kgwgk 8y ago
A second remark:
> Whichever he chooses, the color will be the same as that on the corresponding side of the full-size coin that Alice inserted into Vending Machine A.
The full-size coin that Alice inserted into Vending Machine A is no more (more precisely, its original state is lost). I don't think it makes sense to say that the color would be the same as in a measurement that was never done and can never be done. But I guess you can say that the probability distribution of the colors he will see, no matter what side he chooses, will be the same as if he had looked at the original full-size coin held by Alice.
- lisper 8y ago> The full-size coin that Alice inserted into Vending Machine A is no more (more precisely, its original state is lost). That's true, but the presumption is that the original was prepared in such a way that its state is known. > the probability distribution of the colors he will see, no matter what side he chooses, will be the same as if he had looked at the original full-size coin held by Alice. Exactly.
- kgwgk 8y agoThe presumption is that the original state is unknown. If the state was known, Bob would just need to prepare it in the same way. There is no need for an entangled pair and a destructive procedure to create a copy in that case.
- lisper 8y agoOh yeah, good point. I guess I was thinking that if you wanted to experimentally verify that the state was being reproduced you could start with a known prepared state.
- kgwgk 8y agoI still don't understand what do you mean by "the color will be the same as that on the corresponding side of the full-size coin that Alice [had]". The original one will be lost; you can recreate a new one in the same state but this doesn't mean that "the color will be the same". If they have each a coin prepared as "heads = blue", looking at the other side they will find "tails = red" or "tails = green" without any correlation. Edit: If you mean that the probability distribution of outcomes will be the same for any measurement then of course I do agree; this is why we can say that "the state of Alice's particle is teleported intact to Bob". :-)
- lisper 8y agoYes, you're right. I guess I was making too many concessions to classic intuition.