## Nondivergent classical response functions from uncertainty principle: Quasiperiodic systems

Time-divergence in linear and nonlinear classical response functions can be removed by taking a phase-space average within the quantized uncertainty volume O(({Dirac_h}/2{pi}){sup n}) around the microcanonical energy surface. For a quasiperiodic system, the replacement of the microcanonical distribution density in the classical response function with the quantized uniform distribution density results in agreement of quantum and classical expressions through Heisenberg's correspondence principle: each matrix element <u|{alpha}(t)|v> corresponds to the (u-v)th Fourier component of {alpha}(t) evaluated along the classical trajectory with mean action (J{sub u}+J{sub v})/2. Numerical calculations for one- and two-dimensional systems show good agreement between quantum and classical results.more »