Local randomness from no-signaling-boundary quantum correlations

Chun-Yu Chen^1,2,3*, Gelo Noel M. Tabia^2,3,4, Kai-Siang Chen^2,3, Yeong-Cherng Liang^2,3,4

¹Institute of Information Science, Academia Sinica, Taipei, Taiwan
²Physics, National Cheng Kung University, Tainan, Taiwan
³Center for Quantum Frontiers of Research & Technology, National Cheng Kung University, Tainan, Taiwan
⁴Physics Division, National Center for Theoretical Sciences, Taipei, Taiwan

* Presenter:Chun-Yu Chen, email:L26114209@gs.ncku.edu.tw

In a two-party nonlocal game, when the parties or players get a super-classical score, then some intrinsic randomness can be extracted from the outcomes. Typically, we consider global randomness from the perspective of a third party, but it has been proven that we can also extract some local randomness for one party such that the outcomes of the party are unpredictable from the point of view of the other party. In this work, we show that for certain classes of quantum correlations on the no-signaling boundary, we can extract more local randomness for a given fixed Clauser-Horne-Shimony-Holt value. We discuss its possible applications in mistrustful cryptography.

Keywords: Local Randomness, Nonlocal Game, No-Signaling Boundary, Entropy, Quantum Mistrustful Cryptography