Real-time correlators in Kerr/CFT correspondence

TL;DR

This work computes real-time correlators for perturbations in near-horizon Kerr geometries using a warped AdS/CFT framework. By applying the Minkowskian holographic prescription, it derives retarded Green's functions, cross sections, and quasinormal modes for scalars and higher-spin fields in near-NHEK, NHEK, and Kerr-Newman variants, demonstrating exact agreement with the corresponding 2D CFT predictions once angular warping factors are accounted for. The results reinforce Kerr/CFT as a holographic duality between near-horizon gravity and a chiral (left-moving) CFT, while extending the analysis to charged and higher-dimensional cases. The study also clarifies how real-time holography works in warped AdS spacetimes and outlines future directions related to boundary conditions and broader generalizations.

Abstract

We study real-time correlators in the Kerr/CFT correspondence. The near-horizon geometry of extreme and near-extremal Kerr black holes can be taken as warped spacetimes with the warping factors depending on the transverse radius and the angular variable. By considering the Kerr/CFT correspondence as a generalized warped AdS/CFT correspondence, we show how to compute the CFT real-time correlation functions. We find that the retarded Green's functions, the cross sections and the quasi-normal modes are all in perfect match with the predictions of the dual CFT. The same analysis is also generalized to the charged Newman-Kerr black holes .