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arXiv · 2012.01620

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

Pengfei Zhang·Yingfei Gu·Alexei Kitaev
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Abstract

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.

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Pengfei Zhang, Yingfei Gu, Alexei Kitaev. 2020-12-03. An obstacle to sub-AdS holography for SYK-like models. https://doi.org/10.1007/jhep03(2021)094

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