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Negative Kinetic Energy Between Past and Future State Vectors

Daniel Rohrlich·Yakir Aharonov·Sandu Popescu·Lev Vaidman
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Abstract

An analysis of errors in measurement yields new insight into classically forbidden quantum processes. In addition to "physical" values, a realistic measurement can yield "unphysical" values; we show that in {\it sequences} of measurements, the "unphysical" values can form a consistent pattern. An experiment to isolate a particle in a classically forbidden region obtains a negative value for its kinetic energy. It is the {\it weak value} of kinetic energy between past and future state vectors.

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Daniel Rohrlich, Yakir Aharonov, Sandu Popescu, Lev Vaidman. 1994-06-29. Negative Kinetic Energy Between Past and Future State Vectors. https://doi.org/10.1111/j.1749-6632.1995.tb38982.x

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