High temperature expansion of double scaled SYK

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.