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Quantum physics

Observing and the observed

Quantum mechanics states that the measurement process can fundamentally alter what is being measured. This 'back-action' has been observed on the macroscopic scale — in the vibrations of a tiny mechanical device.

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Figure 1: Cooper-pair molasses in action.




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Roukes, M. Observing and the observed. Nature 443, 154–155 (2006).

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