Preskill: Quantum entanglement does not enable faster-than-light communication
John Preskill · John Preskill on Quantum Computing · Y Combinator · May 16, 2018 · at 59:19
Theoretical physicist John Preskill dispels a common misconception about quantum non-locality and entanglement.
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“What sometimes Gets said, or the impression people get, is that that means that when I do something to my qubit, it instantaneously affects your qubit, even if we're on different sides of the galaxy. But that's not what entanglement does. It just means they're correlated in a certain way. And when you look at yours, if we have maximally entangled qubits, you just see a random bit. You know, it could be A zero or a one, each occurring with probability one half. And that's going to be true no matter what I did to my qubit, and so you can't tell what I did by just looking at it.”
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