Coexistence of Past and Future Measurements' Effects, Predicted by the Two-State-Vector-Formalism and Revealed by Weak Measurement

Yakir Aharonov, Eliahu Cohen, Avshalom C. Elitzur

Published Jul 3, 2012• 0 citations

Abstract

We analyze an idealized experiment in which weak which-path measurements do not prevent consecutive weak interference measurements, and then again the which-path information is recovered by strong measurements. We also show how the same effect can be obtained even by all strong and weak measurements being carried out on a single particle. The simplified setting enables critically assessing competing interpretations of the results. The most natural one turns out to be that of the Two-State-Vector Formalism, according to which the quantum two-state between an earlier and a later measurement is equally determined by both of them.

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