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DOE OSTI · 1801776

Notes on the complex Sachdev-Ye-Kitaev model

Gu, Yingfei·Kitaev, Alexei·Sachdev, Subir·Tarnopolsky, Grigory
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Abstract

We describe numerous properties of the Sachdev-Ye-Kitaev model for complex fermions with N $\gg$ 1 flavors and a global U(1) charge. We provide a general definition of the charge in the ( G, Σ) formalism, and compute its universal relation to the infrared asymmetry of the Green function. The same relation is obtained by a renormalization theory. The conserved charge contributes a compact scalar field to the effective action, from which we derive the many-body density of states and extract the charge compressibility. We compute the latter via three distinct numerical methods and obtain consistent results. Finally, we present a two dimensional bulk picture with free Dirac fermions for the zero temperature entropy.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSAdS-CFT CorrespondenceHolography and condensed matter physics (AdS/CMT)Models of Quantum GravityPhysics

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Gu, Yingfei, Kitaev, Alexei, Sachdev, Subir, Tarnopolsky, Grigory. 2020-02-25. Notes on the complex Sachdev-Ye-Kitaev model. https://doi.org/10.1007/jhep02(2020)157

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