Microscopic Realization of the Kerr/CFT Correspondence

TL;DR

The paper embeds the Kerr/CFT correspondence for extremal 5D Kerr–Newman black holes into a string/M-theory framework by identifying near-horizon AdS$_3$×S$^2$ (and its warped variants) geometries with a dual 2D CFT. In the maximal charge limit, the bulk maps to the well-known $P^3$ (MSW) CFT with $c_L=c_R=6J_L$; linear deformations introduce a nonzero right-moving temperature $T_R$ that reproduces the Kerr–Newman entropy via Cardy, while finite deformations lead to warped AdS$_3$ and a deformed CFT dual. The authors provide an explicit 6D lift and a concrete brane construction realizing the MSW/CFT, and they analyze explicit deformations at linear order and beyond, arguing for a consistent holographic interpretation across regimes. This work situates Kerr/CFT within a concrete string-theoretic context and offers a path to exact microscopic checks of the correspondence through known CFT techniques and brane engineering.

Abstract

Supersymmetric M/string compactifications to five dimensions contain BPS black string solutions with magnetic graviphoton charge P and near-horizon geometries which are quotients of AdS_3 x S^2. The holographic duals are typically known 2D CFTs with central charges c_L=c_R=6P^3 for large P. These same 5D compactifications also contain non-BPS but extreme Kerr-Newman black hole solutions with SU(2)_L spin J_L and electric graviphoton charge Q obeying Q^3 \leq J_L^2. It is shown that in the maximally charged limit Q^3 -> J_L^2, the near-horizon geometry coincides precisely with the right-moving temperature T_R=0 limit of the black string with magnetic charge P=J_L^{1/3}. The known dual of the latter is identified as the c_L=c_R=6J_L CFT predicted by the Kerr/CFT correspondence. Moreover, at linear order away from maximality, one finds a T_R \neq 0 quotient of the AdS_3 factor of the black string solution and the associated thermal CFT entropy reproduces the linearly sub-maximal Kerr-Newman entropy. Beyond linear order, for general Q^3<J_L^2, one has a finite-temperature quotient of a warped deformation of the magnetic string geometry. The corresponding dual deformation of the magnetic string CFT potentially supplies, for the general case, the c_L=c_R=6J_L CFT predicted by Kerr/CFT.