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Quantum Memory Effects in the Measurement of Observables with a Continuous Spectrum

Kai J. Druhl
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Abstract

In the measurement of a continuous observable Q, the pure components of the reduced state do, in general, depend on the initial state. For measurements which attempt to localize the measured system in a certain region R, the localized wave functions are proportional to the original wave function outside of R. This `quantum memory' effect shows that it is not possible to perfectly localize a quantum particle.

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Kai J. Druhl. 1993-04-30. Quantum Memory Effects in the Measurement of Observables with a Continuous Spectrum. https://arxiv.org/abs/hep-ph/9304322

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