The Magical Number Seven: Shared Entanglement versus Communication of a Quantum System in a CGLMP type game By Marek Zukowski

https://www.academia.edu/74158006/The_Magical_Number_Seven_Shared_Entanglement_versus_Communication_of_a_Quantum_System_in_a_CGLMP_type_game?sm=b&rhid=40222982448 Shared entanglement and communication of a quantum system are the two quantum resources for information processing. They exhibit a very intimate relationship. Qualitatively, many information processing tasks can be performed using either quantum resource. Quantitatively, the two resources often yield the same numbers for efficiencies in information processing. However, this equivalence is not always present and there are known cases when shared entanglement is more useful as a resource. Here we show the opposite behaviour: that there exists a family of games where communication of a quantum system is a more powerful resource than sharing entanglement. We introduce our family of games based on the CGLMP inequality, and investigate their efficiency with each quantum resource. We find that for low dimensions, the two resources are equivalent. However, for dimension seven and above, the equivalency is suddenly broken and communication of a quantum system becomes more powerful than shari... ...