Analytic results for the effective action. Thermodynamics and horizon structure. Geodesic focussing and defocussing in Lorentzian spacetimes. Entropy as a surface term. Natural wormholes as gravitational lenses.
Scale anomalies imply violation of the averaged null energy condition.
Full length technical monograph. American Institute of Physics Press, July 1995. An unexpected example of Lorentzian geometry. Submitted for publication. New book by Matt Visser.