Acta Physica Sinica
THE CLOSED TIME PATH GREEN'S FUNCTIONS AND THE THEORY OF NONLINEAR RESPONSE (Ⅰ)
WANG WAI-TONG, LIN ZHONG-HENG, Zhao-Bin Su, Hao Bai-lin, (1)复旦大学; (2)中国科学院理论物理研究所
Abstract
By using the generating functional and the transformations for different forms of the closed time path Green's functions, the general equations on nonlinear response are derived. On the basis of the algebraic identities, KMS condition, time reversal inva-riance and spectral representation, the general considerations for seeking the relations among many-point functions are suggested.