After reading a paper about how quantum mechanics within quantum mechanics can lead to contradictions, I will never look at matryoshka dolls the same way again.

But quantum mechanics doesn’t let me measure it in a general way; I can't ask "hey, Frank-the-quantum-particle, which direction is your spin pointing?"

In this case, he will pick up or down at random.

Outside the box, Bob will try to predict the outcome of the measurement and then measure the entire box to obtain the outcome.

Bob argues that the spin is in a superposition state of up and down, while I, having already made the measurement, say that it is down.

In all cases, the disagreement revolves around the lack of shared knowledge.

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