De Finetti theorems and entanglement in large-N theories and gravity

Understand

The de Finetti theorem and its extensions concern the structure of multipartite probability distributions with certain symmetry properties, the paradigmatic original example being permutation symmetry.

• These theorems assert that such symmetric distributions are well approximated by convex combinations of uncorrelated ones.
• In this article, we apply de Finetti theorems to quantum gravity theories, such as the Sachdev-Ye-Kitaev (SYK) model or large-N vector and gauge theories.
• For SYK we put recent studies of information/entanglement dynamics in a general and rigorous basis.