QuantumBounds / CONCEPT

The realizability conjecture for chained monogamy relations

Kłobus, Oszmaniec, Augusiak and Grudka (arXiv:1408.1223, Section 5) conjecture that every vector of the correlators x_A^i, y_A^i, x_B^i, y_B^i satisfying their inequalities (ElPrat) is realized by a signaling box whose chained Bell expression plus twice the correlator of B_0 and E equals 2M + Delta. This holds for every number of settings M at least 2 and every Delta in [0, 2]: an explicit box realizes the coordinates, has all one- and three-party expectation values zero and a common value of the correlator of B_0 and E, and attains R_M = 2M + Delta exactly.