Information causality beyond the random-access-code model
Phys. Rev. A 114, 012202 – Published 8 July, 2026
DOI: https://doi.org/10.1103/s52j-2jr7
Abstract
Information causality (IC) was one of the first principles invoked to bound a 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 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 this definition is still obeyed by quantum correlations in the same scenario.
