标题： SYK类模型的次AdS全息论的障碍 显示英文标题

标题： An obstacle to sub-AdS holography for SYK-like models

摘要： 我们认为SYK类似模型在假定的重力对偶图像中的“弦性”效应与分支时间有关，该分支时间是根据延迟核以定义的运动学系数。假设主导图为具有细横档的梯子图，建立了分支时间的界限。因此，此类模型不太可能是亚AdS全息的候选者。在弱耦合极限下，我们使用两种不同的近似方法推导出分支时间、Lyapunov指数和准粒子寿命之间的关系。 显示英文摘要

摘要： We argue that "stringy" effects in a putative gravity-dual picture for SYK-like models are related to the branching time, a kinetic coefficient defined in terms of the retarded kernel. A bound on the branching time is established assuming that the leading diagrams are ladders with thin rungs. Thus, such models are unlikely candidates for sub-AdS holography. In the weak coupling limit, we derive a relation between the branching time, the Lyapunov exponent, and the quasiparticle lifetime using two different approximations.