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Sending Signals to Space-Like Separated Regions

Y. Aharonov·L. Vaidman
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Abstract

Two recent works suggest a possibility of sending signals to a space-like separated region, contrary to the spirit of special relativity. In the first work [J. Grunhaus, S. Popescu, and D. Rohrlich, Phys. Rev. A 53, 3781 (1996)] it has been shown that sending signals to particular union of space-like separated region cannot cause causality paradoxes. Another work [Y. Aharonov and L. Vaidman, Phys. Rev. A 61, 052108 (2000)] showed that the relative phase of quantum superposition of a particle in two separate locations can be measured locally. Together with the possibility of changing the relative phase in a nonlocal way using potential effect we, apparently, have a method of sending signals to space-like separated regions. These arguments are critically analyzed in this paper.

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Y. Aharonov, L. Vaidman. 2001-02-16. Sending Signals to Space-Like Separated Regions. https://doi.org/10.1515/zna-2001-0105

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