Quadratic sequences translate chinese12/9/2023 ![]() ![]() The ground states of contextual Hamiltonians are entangled, even though locally they may appear separable. More interestingly, for several Bell inequalities, we find the maximum violation compatible with the laws of quantum mechanics, and identify the Hamiltonians achieving it. In other scenarios, we give evidence that some Bell inequalities require quantum systems of high enough local dimension to be violated. Our results show that some a priori promising Bell scenarios are unlikely to show any form of contextuality, even if we allow greater-than-quantum correlations. We focus on three different Bell scenarios, which differ in the number of measurement settings available to each party and the size of the near-neighbor marginals considered. In this work, building on earlier characterizations of classical local behavior in many-body systems 9, we investigate under which conditions the n-nearest neighbor statistics of a translation-invariant 1D quantum system evidence that the latter is contextual, by exploiting the connection between contextuality and Bell nonlocality. However, very little is known about the strengths and limits of the quantum models which violate these witnesses. Translation and permutation symmetry allowed the full characterization of contextuality witnesses in many-body systems through bipartite correlators only 9, 10, 11, 12 (see ref. Contextuality witnesses adapted from Bell inequalities have been tested in Bose–Einstein condensates 7, 8. ![]() In recent years, the exploration of contextuality in quantum many-body systems has been a fruitful endeavor. For the last scenario, which generalizes the Heisenberg model, we give strong evidence that, in order to exhibit contextuality, the dimension of the local quantum system must be at least 3. ![]() For the second one, we identify several low-dimensional models that reach the ultimate quantum limits, paving the way for self-testing ground states of quantum many-body systems. For the first scenario, we give strong evidence that it cannot exhibit contextuality, not even in non-signaling physical theories beyond quantum mechanics. We investigate contextuality arising from three Bell scenarios in infinite, translation-invariant 1D models: nearest-neighbor with two dichotomic observables per site nearest- and next-to-nearest neighbor with two dichotomic observables per site, and nearest-neighbor with three dichotomic observables per site. In recent years there has been a growing interest in treating many-body systems as Bell scenarios, where lattice sites play the role of distant parties and only near-neighbor statistics are accessible. ![]()
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |