Bell violation by the vacuum at arbitrarily large distances
Decide whether the vacuum of a free massive scalar field violates the CHSH inequality between bounded regions at arbitrarily large distances.
Problems
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Matching problems
Smallest output dimension for a minimum-output-entropy violation
Find the smallest output dimension in which two quantum channels violate additivity of minimum output entropy; it lies between 2 and 182.
Additivity of minimum output entropy for qubit channels
Prove or refute that minimum output entropy is additive when one of two channels is an arbitrary, possibly non-unital, qubit channel.