Experimental Genuine Quantum Nonlocality in the Triangle Network

In the last decade, it was understood that quantum networks involving severalindependent sources of entanglement which are distributed and measured byseveral parties allowed for completely novel forms of nonclassical quantumcorrelations, when entangled measurements are performed. Here, weexperimentally obtain quantum correlations in a triangle network structure, andprovide solid evidence of its nonlocality. Specifically, we first obtain theelegant distribution proposed in (Entropy 21, 325) by performing a six-photonexperiment. Then, we justify its nonlocality based on machine learning tools toestimate the distance of the experimentally obtained correlation to the localset, and through the violation of a family of conjectured inequalities tailoredfor the triangle network.