AdS2/CFT1 correspondence and near-extremal black hole entropy

We provide a realization of the AdS(2)/CFT1 correspondence in terms of asymptotic symmetries of the AdS(2) x S-1 and AdS(2) x S-2 geometries arising in near-extremal BTZ and Reissner-Nordstrom black holes. We evaluate the corresponding central charges and show that Cardy's formula exactly accounts for the deviation of the Bekenstein-Hawking entropy from extremality. We also argue that this result can be extended to more general black holes near extremality. (C) 2000 Elsevier Science B.V. All rights reserved.