Non-Perturbative Corrections to Charged Black Hole Evaporation

Abstract: The recent work of Brown et al. (arXiv:2411.03447) demonstrated that the low-temperature evaporation rate of a large near-extremal charged black hole is significantly reduced from semiclassical expectations. The quantum corrections responsible for the deviation come from Schwarzian modes of an emergent Jackiw-Teitelboim gravity description of the near-horizon geometry of the black hole. Using a one-parameter family of non-perturbative Airy completions, we extend these results to incorporate non-perturbative effects. At large parameter value, the non-perturbative evaporation rate is even smaller than the perturbative JT gravity results. The disparity becomes especially pronounced at very low energies, where the non-perturbative neutral Hawking flux is suppressed by a double exponential in the entropy of the black hole, effectively stopping its evaporation until the next charged particle is emitted via the Schwinger effect. We also explore an alternative family of Bessel completions for which the non-perturbative energy flux exceeds the perturbative JT gravity prediction.