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arXiv · 1912.10222

Operational formulation of weak values without probe systems

Kazuhisa Ogawa·Hirokazu Kobayashi·Akihisa Tomita
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Abstract

Weak values are the fundamental values for observables in a pre- and post-selected system. Weak values are typically measured by weak measurement, in which weak values appear in the change of not the pre- and post-selected system but the probe system. This indirect characteristic of weak measurement obscures the meaning of weak values for the pre- and post-selected system, in contrast to conventional physical quantities, which have a clear operational meaning. In this study, we operationally formulate weak values as the sensitivity of post-selection probability amplitude to small transformation in a pre- and post-selected system. This formulation of weak values, which is free from the concept of probe shift assumed in weak measurement, gives a direct interpretation of strange weak values for the pre- and post-selected system. We further explain that this formulation can simplify weak-value measurement experiments because no probe system is required.

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Kazuhisa Ogawa, Hirokazu Kobayashi, Akihisa Tomita. 2019-12-21. Operational formulation of weak values without probe systems. https://doi.org/10.1103/physreva.101.042117

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