IAS Quantum Aspects of Black Holes Group Meeting
On the Phase of the de Sitter Density of States
Abstract: I will briefly review one-loop gravitational path integral around Euclidean de Sitter space $S^D$, focusing on a complex phase which was recently proposed to be mostly canceled by including an observer. I will then explore this proposal in the case where the observer is a charged black hole in equilibrium with the de Sitter horizon. Using both numerical and analytical methods, the phase of the one-loop determinant within a two-dimensional dilaton gravity reduction matches with previous studies of a probe geodesic observer. I will also revisit the prescription for going from the Euclidean path integral to the state-counting partition function, finding a positive sign in the final density of states. This talk is based on a recent work with Yiming Chen, Douglas Stanford, and Zhenbin Yang.