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arXiv · 1905.13501

Pre- and post-selection paradoxes in quantum walks

Tomasz Kopyciuk·Mikolaj Lewandowski·Pawel Kurzynski
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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.

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Tomasz Kopyciuk, Mikolaj Lewandowski, Pawel Kurzynski. 2019-05-31. Pre- and post-selection paradoxes in quantum walks. https://arxiv.org/abs/1905.13501

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