High temperature expansion of double scaled SYK

Kazumi Okuyama

doi:10.1016/j.physletb.2023.138036

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arXiv · 2304.01522

High temperature expansion of double scaled SYK

Kazumi Okuyama

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Abstract

We study the high temperature (or small inverse temperature $\beta$) expansion of the free energy of double scaled SYK model. We find that this expansion is a convergent series with a finite radius of convergence. It turns out that the radius of convergence is determined by the first zero of the partition function on the imaginary $\beta$-axis. We also show that the semi-classical expansion of the free energy obtained from the saddle point approximation of the exact result is consistent with the high temperature expansion of the free energy.

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Kazumi Okuyama. 2023-04-04. High temperature expansion of double scaled SYK. https://doi.org/10.1016/j.physletb.2023.138036

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