Deciphering Quantum Enigmas: The Role of Nonlocal Boxes in Defining The Boundaries of Physical Feasibility https://thequantuminsider.com/?p=2360948 #Research #Canada #entanglement #Physical_Review_Letters #Tsirelson's_bound #University_of_Ottawa #quantumdaily Insider Brief Researchers report that various quantum theory extensions are considered non-physical when tested against the principle of non-trivial communication complexity. The team uses an array of nonlocal boxes, which are theoretical

obtaining a #Tsirelson bound for a given Bell inequality is a hard problem that has to be solved case-by-case not known to be decidable. best way upperbounding it is a convergent hierarchy of semidefinite programs, the NPA hierarchy, that in general does not halt.