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A comment on Quantum ‘spookiness’ passes toughest test yet. Parent comment

Re:Quantum ‘spookiness’ passes toughest test yet by coldtea on Sunday August 30, 2015 @07:40AM (#10143044)
>The similarity to 2 coins is: if i have a 1972 coin and a 1973 coin, and give one to you randomly, then you go a million light years away and look at your coin and find you have the 1973 coin, you will know I have the 1972 coin. Although this is only a simplified analogy of entanglement the important point is that the state was prepared before we separated, and no information has been communicated. When you try to understand this in terms of classical physics, it's weird.

If that was the case (the coin analogy) it would be perfectly understandable by classical physics.

In fact it wouldn't even need physics to understand it, just common sense.

If that was the case there wouldn't be any EPR paradox etc.

The coin analogy is very misleading in this way -- and doesn't convey the problems physicists have had with explaining this phenomenon.

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Re:Quantum ‘spookiness’ passes toughest test yet by dools on Sunday August 30, 2015 @07:56PM (#10144836)
No what I'm describing is a way of understanding why entangled states aren't spooky. It's also a direct lift from Leonard Susskind so it's not even me doing it. The point is that the state is prepared in some way X, and the state is such that by knowing something about one thing, you also know something about the other thing.

The actual mechanism by which this occurs is only "spooky" if you try and interpret it classically. But if you just accept that "hey, it's quantum mechanics" then it's very easy to understand. Same as I can't visualise a 5-sphere but I have mathematical tools to work with one.

I can't "picture" the mechanism that allows measurements of quantum states to be anti-correlated, but I can use maths to express that behaviour and make predictions about how the universe behaves.

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Re:Quantum ‘spookiness’ passes toughest test yet by coldtea on Monday August 31, 2015 @04:37AM (#10145981)
>No what I'm describing is a way of understanding why entangled states aren't spooky.

I think that if the explanation doesn't also convey the spookiness, it's not right.

>The actual mechanism by which this occurs is only "spooky" if you try and interpret it classically. But if you just accept that "hey, it's quantum mechanics" then it's very easy to understand.

That's just pushing the spookiness under the carpet.

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Re:Quantum ‘spookiness’ passes toughest test yet by dools on Tuesday September 01, 2015 @06:30AM (#10151583)
The original phrase is spooky action at a distance, which has been summarised as spookiness. Actual spookiness notwithstanding, the most important thing really is that there is no action at a distance.
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