Generalized hidden Kerr/CFT
  We construct a family of vector fields that generate local symmetries in the solution space of low frequency massless field perturbations in the general Kerr geometry. This yields a one-parameter family of SL(2,R)x SL(2,R) algebras. We identify limits in which the SL(2,R)xSL(2,R) algebra contracts to an SL(2,R) symmetry of the Schwarzschild background. We note that for a particular value of our new free parameter, the symmetry algebra generates the quasinormal mode spectrum of a Kerr black hole in the large damping limit, suggesting a connection between the hidden conformal symmetry and a fundamental CFT underlying the quantum Kerr black hole. 
David A. Lowe and Antun Skanata
hep-th