LOCALIZATION, NONLINEAR SIGMA-MODEL AND STRING THEORY

The Anderson localization problem is studied by the renormalization group analysis of the string theory. The renormalization group functions of the Anderson localization are obtained from the scattering amplitudes of the string background fields. The higher derivative terms and the higher moments of the fields, which are relevant to the higher moments of the conductance fluctuation, are investigated in terms of the dilaton and the massive fields of the string theory. Nonperturbative effects are discussed based upon the string theory.