Relativistic independence and multipartite quantum correlations

Abstract Multipartite quantum correlations are complex and intricate, posing challenges for their detection and quantification. Nevertheless, they are central to both fundamental quantum science and its numerous applications. We discuss several approaches for analyzing quantum correlations, with an emphasis on the Relativistic Independence framework which allows one to detect and differentiate classes of multipartite entangled states, while also yielding refined quantum bounds on multipartite systems. This framework is shown to rely on a recently demonstrated tradeoff between local and nonlocal correlations, signifying the enabling power of quantum uncertainty. Furthermore, we examine these notions from the broader perspective of quantum reference frames (QRFs), attempting to see which of the above concepts are perspective-dependent and which are not. Large parts of the current discussion, as well as many of the quantitative results presented, specifically rely on the structure of the covariance matrix, whose determinant remains invariant under QRF changes, thereby signaling its fundamental significance.