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Title: Can a future choice affect a past measurement’s outcome?

An EPR experiment is studied where each particle within the entangled pair undergoes a few weak measurements (WMs) along some pre-set spin orientations, with the outcomes individually recorded. Then the particle undergoes one strong measurement along an orientation chosen at the last moment. Bell-inequality violation is expected between the two final measurements within each EPR pair. At the same time, statistical agreement is expected between these strong measurements and the earlier weak ones performed on that pair. A contradiction seemingly ensues: (i) Bell’s theorem forbids spin values to exist prior to the choice of the orientation measured; (ii) A weak measurement is not supposed to determine the outcome of a successive strong one; and indeed (iii) Almost no disentanglement is inflicted by the WMs; and yet (iv) The outcomes of weak measurements statistically agree with those of the strong ones, suggesting the existence of pre-determined values, in contradiction with (i). Although the conflict can be solved by mere mitigation of the above restrictions, the most reasonable resolution seems to be that of the Two-State-Vector Formalism (TSVF), namely, that the choice of the experimenter has been encrypted within the weak measurement’s outcomes, even before the experimenters themselves know what their choicemore » will be.« less
Authors:
 [1] ;  [2] ;  [3] ;  [1] ;  [4]
  1. School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 6997801 (Israel)
  2. (United States)
  3. (Israel)
  4. Iyar, The Israeli Institute for Advanced Research, Rehovot (Israel)
Publication Date:
OSTI Identifier:
22451155
Resource Type:
Journal Article
Resource Relation:
Journal Name: Annals of Physics; Journal Volume: 355; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BELL THEOREM; QUANTUM ENTANGLEMENT; SPIN ORIENTATION; VECTORS