On the Quenched Free Energy of JT Gravity and Supergravity

The quenched free energy, $F_Q(T){=}{-}T\langle \ln Z(T)\rangle$, of various JT gravity and supergravity theories is explored, taking into account the key non-perturbative physics that is accessible using their matrix model formulations. The leading low energy physics of these systems can be modelled by the Airy and (a family of) Bessel models, which arise from scaling limits of matrix ensembles. The $F_Q(T)$s of these models are directly computed by explicit sampling of the matrix ensembles, and how their properties are connected to the statistical mechanics of the underlying discrete spectrum of the ensembles is elucidated. Some of the low temperature ($T$) features of the results confirm recent observations by Jassen and Mirbabayi. The results are then used as benchmarks for exploring an intriguing formula proposed by Okuyama for computing $F_Q(T)$ in terms of the connected correlators of its partition function, the wormholes of the gravity theory. A low $T$ truncation of the correlators helps render the formula practical, but it is shown that this is at the expense of much of its accuracy. The significance of the statistical interpretation of $F_Q(T)$ for black hole microphysics is discussed.