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No-cloning theorem and distinguishing between two non-orthogonal quantum states revisited revisited

I think what you asking about is the following setting: you are given a qubit which is either $|\psi\rangle$ or $|\psi'\rangle$ with are not orthogonal. You know what those two possible states are, ...
DaftWullie's user avatar
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No-cloning theorem and distinguishing between two non-orthogonal quantum states revisited revisited

The crucial point about the no-cloning theorem is (as you already suspect) the basis choice. You can always find a specific cloning machine for a specific basis, but you cannot find a general cloning ...
qubitzer's user avatar
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2 votes
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How to show that BB84 is safe against imperfect cloning?

If you impose that $U|\psi\rangle|0\rangle=|\psi\rangle|\psi'\rangle$ for all $|\psi\rangle$ (or at least for a pair of non-orthogonal states), then you'll be able to prove that $|\psi'\rangle$ must ...
DaftWullie's user avatar
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3 votes
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Hypothesis on faster-than-light communication

If Alice is performing a CNOT on her and Bobs qubits, Bob (and his qubit) will need to be close to Alice. No matter how they prepare the state, once they are separated, local operations will not ...
john's user avatar
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