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arXiv · 1604.04110

Measuring Unrecorded Measurement

M. Revzen·A. Mann
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Abstract

Projective (Von Neumann) Measurement of an operator (i.e. a dynamical variable) selected from a prescribed set of operators is termed unrecorded measurement (URM) when both the selected operator and the measurement outcome are unknown, i.e. "lost". Within classical physics a URM is completely inconsequential: the state is unaffected by measurement. Within quantum physics a measurement leaves a mark. The present study provides protocols that allow retrieval of some of the data lost in a URM.

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M. Revzen, A. Mann. 2016-04-14. Measuring Unrecorded Measurement. https://doi.org/10.1209/0295-5075%2F115%2F30005

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