The Sachdev-Ye-Kitaev Model and Quantum Chaos in Many-Body Systems

The Sachdev-Ye-Kitaev Model and Quantum Chaos in Many-Body Systems
Jacobus Verbaarschot, SUNY Stony Brook
Jacobus Verbaarschot
Date and time: Thu, Apr 18, 2019 - 11:30am
Refreshments at 11:15am
Location: LGRT 1033
Category: Condensed Matter Seminar
Abstract:

The Sachdev-Ye-Kitaev model was originally introduced in nuclear physics  by French and Mon
to describe the spectral properties of complex nuclei. In condensed matter physics it was
proposed  as a model for a spin liquid by Sachdev and Ye, but the model only really took off a
few years ago after Kitaev introduced it as a model for a black hole. The SYK model is a
paradigm for a non-Fermi liquid which has a zero temperature entropy that is extensive with
a level density that increases exponentially with energy. Because, in addition the model is
chaotic, it has the necessary ingredients for being a quantum mechanical model of a black hole.
In this lecture, we give an elementary introduction of the SYK model, discuss its chaotic
properties in terms of level correlations, and explain the relevant time scales.
In a coupled SYK model that has been proposed as model for a wormhole we find that
eigenstate thermalization gives a good description of the ground state of this model.