Two-Dimensional Dilatonic Black Holes and Hawking Radiation

Hawking radiation emanating from two-dimensional charged and uncharged dilatonic black holes — dimensionally reduced from (2+1) spinning and spinless, respectively, BTZ black holes — is viewed as a tunneling process. Two-dimensional dilatonic black holes (AdS(2) included) are treated as dynamical background in contrast to the standard methodology where the background geometry is fixed when evaluating Hawking radiation. This modification to the geometry gives rise to a nonthermal part in the radiation spectrum. Nonzero temperature of the extremal two-dimensional charged black hole is found. The Bekenstein–Hawking area formula is easily derived for these dynamical geometries.