Multipartite entanglement structure of random quantum states and gravity

Simon Lin (NYU Abu Dhabi)

Entanglement is the defining feature of a quantum system where different parts of the system cannot be factorized as a product. In terms of bipartite entanglement, there are clear diagnostics for whether a system is entangled or not. The situation for multipartite entanglement is less understood. In my talk I will discuss different diagnostics of multipartite entanglements that can be formulated as symmetrized contractions of density matrices of the system: Reflected entropy and (genuine) multi-entropy. For random tensor network states, these signals can be calculated using the replica trick and be reformulated as a combinatorial optimization problem, allowing explicit evaluation in the large $N$ limit. This in turn leads to interesting connections to minimal cut problems on the graph defining the tensor network. Implications for holography and quantum gravity will also be discussed.

Contact : I. Nechita