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## Main Question or Discussion Point

I would like to learn about and clarify the common statement: "QM objects do not have properties until measured".

From

"Put a red slip of paper in an envelope and a green one in another. Send one to the other side of the universe. Open one and you automatically know the colour of the other. The systems are correlated - nothing spooky going on. Now it turns out in QM you can do exactly the same thing with particle spins. And you get correlations. Again nothing mysterious. The difference is it has a different kind of statistical correlation

http://www.drchinese.com/Bells_Theorem.htm

Question: If we did a Bell-test with electron-positron pairs, could we NOT say that each particle in a pair has opposite charge and velocity and that they are correlated by the conservation of angular momentum?

So, it seems, quantum objects have some properties before measurement. What they do not necessarily have is the property measured by each interaction with a detector. That is, in my words, they do not necessarily have spin-up or spin-down before measurement.

So, modifying bhobba's statement:

Is this correct?

From

**bhobba**in the closed thread:**https://www.physicsforums.com/forums/quantum-physics.62/threads/why-the-rush-to-quantum-spookiness.868728/ [Broken]:**"Put a red slip of paper in an envelope and a green one in another. Send one to the other side of the universe. Open one and you automatically know the colour of the other. The systems are correlated - nothing spooky going on. Now it turns out in QM you can do exactly the same thing with particle spins. And you get correlations. Again nothing mysterious. The difference is it has a different kind of statistical correlation

http://www.drchinese.com/Bells_Theorem.htm

**It turns out the reason for that different correlation is that in QM objects do not have properties until measured to have them**. But what if we insist? Then we find there must be instantaneous communication. But only if we insist." (My emphasis.)Question: If we did a Bell-test with electron-positron pairs, could we NOT say that each particle in a pair has opposite charge and velocity and that they are correlated by the conservation of angular momentum?

So, it seems, quantum objects have some properties before measurement. What they do not necessarily have is the property measured by each interaction with a detector. That is, in my words, they do not necessarily have spin-up or spin-down before measurement.

So, modifying bhobba's statement:

**… the different correlation is that QM objects (unlike the red and green slips of paper) do not necessarily have the measured output before measurement. And we find there must be "instantaneous communication" if we insist that they have the measured property (spin-up or spin-down) before measurement.**

Is this correct?

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