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arXiv · 1702.05479

Violation of space-time Bell-CHSH inequality beyond Tsirelson bound via post selection and quantum cryptography

C S Sudheer Kumar
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Abstract

Here we show that, if we insert context dependent unitary evolutions (which can be achieved via post selection) into spatial (i.e., normal) Bell-CHSH test, then it is possible to violate space-time Bell-CHSH inequality maximally (i.e., up to $4$). However this does not contradict Tsirelson quantum bound ($2\sqrt{2}$), as the latter has been derived without taking into consideration context dependent unitary evolutions and/or post selection. As an important application, this leads to a more efficient quantum key distribution protocol.

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C S Sudheer Kumar. 2017-02-17. Violation of space-time Bell-CHSH inequality beyond Tsirelson bound via post selection and quantum cryptography. https://doi.org/10.1007/s12043-019-1830-3

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