Journal of High Energy Physics

, 2017:149 | Cite as

Eigenstate thermalization in the Sachdev-Ye-Kitaev model

Open Access
Regular Article - Theoretical Physics


The eigenstate thermalization hypothesis (ETH) explains how closed unitary quantum systems can exhibit thermal behavior in pure states. In this work we examine a recently proposed microscopic model of a black hole in AdS2, the so-called Sachdev-Ye-Kitaev (SYK) model. We show that this model satisfies the eigenstate thermalization hypothesis by solving the system in exact diagonalization. Using these results we also study the behavior, in eigenstates, of various measures of thermalization and scrambling of information. We establish that two-point functions in finite-energy eigenstates approximate closely their thermal counterparts and that information is scrambled in individual eigenstates. We study both the eigenstates of a single random realization of the model, as well as the model obtained after averaging of the random disordered couplings. We use our results to comment on the implications for thermal states of a putative dual theory, i.e. the AdS2 black hole.


AdS-CFT Correspondence Holography and condensed matter physics (AdS/CMT) Models of Quantum Gravity 2D Gravity 


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© The Author(s) 2017

Authors and Affiliations

  1. 1.Department of Theoretical PhysicsUniversity of GenevaGenève 4Switzerland

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