I will revisit the quantum entropy of extremal black holes which is defined as a path integral in the near-horizon AdS2 region. This has been studied in the past using different methods: loop calculations give rise to leading logarithmic corrections to the area law, and localization gives rise to a sum over all perturbative corrections.
The new development has to do with the exact treatment of the zero-modes that appear in the near-horizon region, which can be described by the Schwarzian action at small temperatures. I will show how this allows us to (1) calculate the non-perturbative effects in the localization calculation, so as to get integers degeneracies out of gravity, and (2) control the zero-temperature limit properly for extremal (not necessarily supersymmetric) black holes, leading to new logarithmic effects.
It will be an informal talk based on the papers
https://arxiv.org/abs/2209.13608 , https://arxiv.org/abs/2209.13602
Zoom link: https://icts-res-in.zoom.us/j/84465862906?pwd=RUVoNUdrUmJFdWJERGF6SGlEYVVuUT09
Meeting ID: 844 6586 2906
Passcode: 223322