title: Heisenberg, langevin, and current equations via the recurrence relations approach
abstract: Some years ago the Heisenberg equation of motion was formally solved by the recurrence relations approach. It is shown here that the Langevin equation represents a structural property of the recurrence relations. The Langevin equation is useful for studying the time evolution of the current. The resulting current-current correlation function is compared with Luttinger's phenomenological theory. Geometric interpretations are made for the conductivity and the dielectric function.
authors.affiliation: Korea Institute for Advanced Study, Seoul 130-012, Korea and Department of Physics, University of Georgia, Athens, Georgia 30602*.
authors.initials: MH
authors.lastname: Lee