But remember that, before measurement, both were in a superposition of spinning up and down. After measurement both have distinct states: one of them is up and the other is down. So the second electron has instantly and remotely changed its physical state from being in a superposition of spinning both ways at once to being spin-down—without being touched. All we have done is to measure the state of its partner. And in principle it doesn’t matter how far away this second electron is—it could be on the other side of the universe and the effect would be the same: measuring just one of an
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