High Energy Theory Seminar

In the last decade, it has been understood that the spectrum and dynamics of near-extremal black holes receive quantum gravity corrections that become large at low temperatures. These corrections come from a soft mode in the near-horizon geometry that is strongly coupled at low energies and is governed by a Schwarzian action. In this talk, I will use solutions of the Schwarzian action to discuss how some observables of near-extremal 4d asymptotically flat black holes are modified. In particular, I will compare the Schwarzian-corrected scalar absorption cross sections and emission rates of nearly-BPS black holes in $\mathcal{N} = 2$ supergravity to those of near-extremal black holes in Einstein gravity. I will also discuss how the probability distribution of level occupation evolves with time due to Hawking radiation in both cases. Although the two black holes have similar absorption and emission properties in the semiclassical regime, they behave differently in the low temperature regime where quantum gravity effects are important. This difference can be attributed to the presence of a large ground state degeneracy and a gap in the density of states in the supersymmetric case.

The talk is in 469 Lauritsen.

Contact [email protected] for Zoom information.