Title: Deviations from factorization in SYK

Abstract: Recently, there has been a revived interest in multi-boundary holographic systems and the contribution of Euclidean wormholes, in particular in Jackiw-Teitelboim (JT) gravity. We consider Sachdev-Ye-Kitaev (SYK) as a microscopic model for such holographic systems. While in JT gravity the non-factorizing contributions come from geometric wormholes, we get that in SYK there are much larger contributions. We give a diagrammatic description of all those leading contributions, analogous to Feynman diagrams. The holographic behavior is particularly interesting for fixed SYK couplings due to factorization, and we comment on that as well.