“…It implies that the general Kerr should be dual to a two-dimensioanl CFT with central charges c L = c R = 12J at temperatures (T L , T R ). The entropy of general Kerr black holes computed by using Cardy's formula agrees well with the BH area law for black hole entropy and the result appears to be valid for any values of M and J.More hidden conformal symmetries are found in various black hole spacetimes [9,10,11,12,13,14,15,16,17,18,19,20]. Recently, it is claimed in [21] that there is also an SL(2, R) symmetry in the wave equation in near regions of Schwarzschild black holes.…”