Signature change in two-dimensional black-hole models of loop quantum gravity

Signature change has been identified as a generic consequence of holonomy modifications in spherically symmetric models of loop quantum gravity with real connections, which includes modified Schwarzschild solutions. An extension of this result to two-dimensional dilaton models, including in particular the Callan-Giddings-Harvey-Strominger (CGHS) solution, further elucidates properties of black holes in this setting. In addition, new obstructions are found to coupling matter and to including operator-ordering effects in an anomaly-free manner.