Localization type effects for Schrodinger operators and for the quantum spin systems, percolation and contact processes in disordered environments. Singular continuous spectrum and wave functions. Symmetries for multidimensional quasiperiodic operators. Quantum spin systems, percolation and contact processes in disordered environments. The main subject of Klein's research is the study of phenomena that occur in disordered systems.
Impurities can change dramatically the properties of certain materials.
The best known examples are transistors, which are made of certain materials whose properties are modified by impurities. Such materials are modeled by disordered systems. Klein's research include disordered systems in Quantum Mechanics and in Classical and Quantum Statistical Mechanics. Peter Li Primary research interest is in geometric analysis. In particular, the application of partial differential equations to the study of geometry.