The Overlap Catastrophe

The Overlap Catastrophe is the name given to an interesting discovery made by P.W. Anderson. In a metal, the conduction electrons must be rearranged when a quantum subsystem, say a defect, changes state: the initial and final electron ground-state wavefunctions are so different that the bath of conduction electrons can force the subsystem to dissipate energy during each transition, or even keep the transition from occuring. These conduction electron effects are crucial to understanding the X-ray edge singularity, the Kondo effect, tunneling in SQUIDS, and other interesting effects.
See P.W. Anderson Phys. Rev. Lett. 18, 1049 (1967)
Last modified: May 31, 1994

Ard Louis, ardlouis@lassp.cornell.edu