Quantum Correlations Are Stronger Than All Nonsignaling Correlations Produced by n-Outcome Measurements.

  title={Quantum Correlations Are Stronger Than All Nonsignaling Correlations Produced by n-Outcome Measurements.},
  author={Matthias Kleinmann and Ad{\'a}n Cabello},
  journal={Physical review letters},
  volume={117 15},
We show that, for any n, there are m-outcome quantum correlations, with m>n, which are stronger than any nonsignaling correlation produced from selecting among n-outcome measurements. As a consequence, for any n, there are m-outcome quantum measurements that cannot be constructed by selecting locally from the set of n-outcome measurements. This is a property of the set of measurements in quantum theory that is not mandatory for general probabilistic theories. We also show that this prediction… 

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