Quantum Singularities
  The definitions of classical and quantum singularities in general relativity are reviewed. The occurence of quantum mechanical singularities in certain spherically symmetric and cylindrically symmetric (including infinite line mass)spacetimes is considered. A strong repulsive ``potential'' near the classical singularity is shown to turn a classically singular spacetime into a quantum mechanically nonsingular spacetime. 
D.A. Konkowski, T.M. Helliwell, and C. Wieland