Information causality beyond the random access code model
arXiv:2201.08986 · doi:10.1103/s52j-2jr7
The paper introduces a new quantifier for information causality based on redundant information, which closes several gaps between the principle and the quantum set of correlations, and provides numerical evidence that quantum correlations still satisfy this refined principle without relying on random access codes.
Abstract
Information causality (IC) was one of the first principles that have been invoked to bound the set of quantum correlations. For some families of correlations, this principle recovers exactly the boundary of the quantum set; for others, there is still a gap. We close some of these gaps using a new quantifier for IC, based on the notion of ``redundant information''. This progress was made possible by the recognition that the principle of IC can be captured without referring to the success criterion of random access codes. We give strong numerical evidence that the new definition is still obeyed by quantum correlations in the same scenario.
6 pages, 3 figures, 1 table