Lieb-Robinson bounds on n -partite connected correlation functions
Minh C. Tran, James R. Garrison, Zhexuan Gong, Alexey Vyacheslavovich Gorshkov · Physical Review A · 2017
Lieb and Robinson provided bounds on how fast bipartite connected correlations can arise in systems with only short-range interactions. We generalize Lieb-Robinson bounds on bipartite connected correlators to multipartite connected correlators. The bounds imply that an $n$-partite connected correlator can reach unit value in constant time. Remarkably, the bounds also allow for an $n$-partite connected correlator to reach a value that is exponentially large with system size in constant time, a feature which stands in contrast to bipartite connected correlations. We provide explicit examples of such systems.