Pre- and post-selection paradoxes in quantum walks
Abstract
Many features of single-partite quantum walks can be simulated by classical waves. However, it was recently experimentally shown that some temporal sequences of measurements on a quantum walker do not admit a classical description in terms of macro-realistic theories. Here, we extend this observation and present pre- and post-selection scenarios in quantum walks leading to logical paradoxes. Such paradoxes were recently shown to be equivalent to proofs of contextuality, therefore we provide an additional argument for non-classicality of a quantum walk model. The assumptions behind the claims of non-classicality (including contextuality and violations of macro-realism) are also discussed.
Cite
@article{arxiv.1905.13501,
title = {Pre- and post-selection paradoxes in quantum walks},
author = {Tomasz Kopyciuk and Mikolaj Lewandowski and Pawel Kurzynski},
journal= {arXiv preprint arXiv:1905.13501},
year = {2019}
}
Comments
18 pages, 4 figures, comments welcome. This work was originally planed to be an extension of arXiv:1812.00624 (partial overlap of introduction part), however while working on it we found completely new results and departed from the original work