Key points are not available for this paper at this time.
We study the nearest-level-spacing distribution function P (s) in a disordered system near the metal-insulator transition. We claim that in the limit of an infinite system there are only three possible functions P (s): Wigner surmise Pₖ (s) in a metal, Poisson law P (s) in an insulator, and a third one Pₓ (s), exactly at the transition. The function Pₓ is an interesting hybrid of Pₖ (s) and P (s), it has the small-s behavior of the former and the large-s behavior of the latter one. A scaling theory of critical behavior of P (s) in finite samples is proposed and verified numerically.
Shklovskiǐ et al. (Sat,) studied this question.