Space-Time in the SYK Model
Sumit R. Das, Animik Ghosh, Antal Jevicki, Kenta Suzuki
TL;DR
The paper tackles the problem of identifying the bulk spacetime dual to the Euclidean SYK model. It demonstrates that a non-local Radon-type transform on bi-local $n$-point Green's functions maps to Euclidean AdS$_2$ with leg factors, signaling coupling to additional bulk states akin to discrete 2D string states. By formulating these Leg transformations as a canonical map in phase space, the work clarifies how Euclidean bulk geometry can be reconciled with the SYK bi-local data and provides a framework for incorporating extra bulk degrees of freedom. The results point toward a richer, nonlocal bulk reconstruction, potentially extending to a three-dimensional perspective and connections to $c=1$ string theory.
Abstract
We consider the question of identifying the bulk space-time of the SYK model. Focusing on the signature of emergent space-time of the (Euclidean) model, we explain the need for non-local (Radon-type) transformations on external legs of $n$-point Green's functions. This results in a dual theory with Euclidean AdS signature with additional leg-factors. We speculate that these factors incorporate the coupling of additional bulk states similar to the discrete states of 2d string theory.
