Vu Hoang
Weak localization in quantum mechanics and optics

In 1976, B. Simon proved that for the Schroedinger operator
in two space dimensions, arbitrarily weak attractive potentials create 
bound states. This is false for the three-dimensional Schroedinger operator.
Recently, there has been renewed interest in the problem of weak localization
in the context of optical waveguides. I discuss a simplified proof of a
part of Simon's theorem by S. Wugalter and recent work on optical waveguides
by Brown, Plum, Radosz, Wood and myself.