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Journal of the Physical Society of Japan

Formal Theory of Nonlinear Response. II. Response to Thermal Disturbances

Masakazu Ichiyanagi

Published Feb 15, 1989• 1 citation

Abstract

This is the second in a series of papers which intends to develop a statistical mechanical theory capable of independently treating responses to thermal as well as mechanical disturbances. The essential idea is to develop a method of solving the Liouvill-von Neumann equation for the density matrix of a many-body system in a time-dependent Gibbsian form. The theory is made determinate by defining the relative entropy, which will reflect the character of the entropy production in our model. In this paper, rigorous expressions are obtained for nonlinear responses, which contain all the most general consequences of statistical mechanics regarding the macroscopic variables. In particular, the Onsager reciprocity relations follow from the formula in nonlinear regions. An attempt to treat a stationary state where heat is produced is made in terms of a nonequilibrium density matrix satisfying the Liouville-von Neumann equation.

DOI: 10.1143/jpsj.58.431

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