FRANK A. WILCZEK
School of Natural Sciences
Institute for Advanced Study
There is much interest currently in the properties of two-dimensional electronic systems. A whole class of new states of matter (the fractional quantized Hall states) has been discovered to be possible for interacting electrons in a layer subjected to a perpendicular magnetic field, and several related but distinct possibilities for additional states have been suggested theoretically. A unified framework for correlating and understanding this variety of states in an elementary way is presented. And, in future columns, additional quantitative work based on the philosophy of perturbing in quantum statistics will be reported.
M. Greiter, F. Wilczek, "Heuristic principle for quantized Hall states," Modern Physics Letters, B4, 1063-9, 1990. (Institute for Advanced Studies, Princeton, N.J.)
In previous columns I have often mentioned articles on various forms of scanning microscopy. This is an extremely dynamic, vigorous, and important field....