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Pre- and post-selection, weak values, and contextuality

Jeff Tollaksen
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Abstract

By analyzing the concept of contextuality (Bell-Kochen-Specker) in terms of pre-and-post-selection (PPS), it is possible to assign definite values to observables in a new and surprising way. Physical reasons are presented for restrictions on these assignments. When measurements are performed which do not disturb the pre- and post-selection (i.e. weak measurements), then novel experimental aspects of contextuality can be demonstrated including a proof that every PPS-paradox with definite predictions implies contextuality. Certain results of these measurements (eccentric weak values with e.g. negative values outside the spectrum), however, cannot be explained by a "classical-like" hidden variable theory.

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Jeff Tollaksen. 2006-07-27. Pre- and post-selection, weak values, and contextuality. https://doi.org/10.1088/1751-8113/40/30/025

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