Non-singular four-dimensional black holes and the Jackiw-Teitelboim theory

Black hole solutions in the context of a generic matter-coup led two-dimensional dilaton gravity theory are discussed both at the classical and semiclassical level. Starting from general assumptions, a criterion for the existence of black holes is given. The relationship between conformal anomaly and Hawking radiation is extended to a broad class of two- dimensional dilaton gravity models. A general and simple formula relating the magnitude of the Hawking effect to the dilaton potential evaluated on the horizon is derived.