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arXiv · hep-th/9305075

Measurements, errors, and negative kinetic energy

Y. Aharonov·S. Popescu·D. Rohrlich·L. Vaidman
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Abstract

An analysis of errors in measurement yields new insight into the penetration of quantum particles into classically forbidden regions. In addition to ``physical" values, realistic measurements yield ``unphysical" values which, we show, can form a consistent pattern. An experiment to isolate a particle in a classically forbidden region obtains negative values for its kinetic energy. These values realize the concept of a {\it weak value}, discussed in previous works.

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Y. Aharonov, S. Popescu, D. Rohrlich, L. Vaidman. 1993-05-17. Measurements, errors, and negative kinetic energy. https://doi.org/10.1103/physreva.48.4084

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