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A comment on Post-quantum cryptography is too damn big. Parent comment

Re:Post-quantum cryptography is too damn big by sesm on Saturday March 23, 2024 @08:24AM (#39799407)
QM doesn’t say anything about how long a system can stay in quantum entangled state, so it doesn’t say what is the limit to computations that can be performed on a quantum computer. Some computations were successfully performed, as QM predicts, but now it seems that researchers are hitting a limit.
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Re:Post-quantum cryptography is too damn big by juitpykyk on Saturday March 23, 2024 @09:37AM (#39799837)
QM says QC as we envision them will work.

QM says a quantum entangled state will remain like that until disturbed/measured. If there is some limit as you suggest, that means QM is at least partially broken.

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Re:Post-quantum cryptography is too damn big by sesm on Saturday March 23, 2024 @06:37PM (#39803525)
That’s right, but it doesn’t specify what exactly is disturbance/measurement. We know from observation that interaction with a macroscopic system causes wave function collapse seemingly instantly. But we don’t know much about in-between behavior, like what happens when interacting with another microscopic system and does wave function of a microscopic quantum system collapse on it’s own given enough time.
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