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arXiv · 1410.5221

Conditions for Anomalous Weak Value

Arun Kumar Pati·Junde Wu
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Abstract

We show that the weak value of any observable in pre- and post-selected states can be expressed as the sum of the average of the observable in the pre-selected state and an anomalous part. We argue that at a fundamental level the anomalous nature of the weak values arises due to the interference between the post-selected state and another quantum state which is orthogonal to the pre-selected state. This provides a necessary and sufficient condition for the anomalous nature of the weak value of a quantum observable. Furthermore, we prove that for two non-commuting observables the product of their anomalous parts cannot be arbitrarily large.

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Arun Kumar Pati, Junde Wu. 2014-10-20. Conditions for Anomalous Weak Value. https://arxiv.org/abs/1410.5221

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