Microscopic Realization of the Kerr/CFT Correspondence

TL;DR

This paper demonstrates how near-horizon geometries of extremal black holes in five-dimensional supergravity relate to dual 2D conformal field theories, extending the Kerr/CFT correspondence to supersymmetric and non-BPS black strings.

Contribution

It explicitly connects the near-horizon limits of extremal black strings and Kerr-Newman black holes to dual CFTs, including warped deformations, confirming and extending the Kerr/CFT correspondence.

Findings

Near-horizon geometry matches the right-moving temperature T_R=0 limit of magnetic black strings.

Thermal CFT entropy reproduces Kerr-Newman entropy at linear order.

Warped deformations of magnetic string geometries suggest dual CFTs for non-maximal charges.

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.