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MH Lee

Publications and source records attributed to MH Lee.

At least 19 recordsLinked to original sources
PubMed2000

Fick's law, green-kubo formula, and Heisenberg's equation of motion

Fick's law is important in transport theory and nonequilibrium statistical mechanics. The Heisenberg equation of motion for density is examined to see how it could be reduced to the diffusion equation, which is exactly equivalent to Fick's law. Conditions that are required have been noted and their implications explored.

Journal Article↗
PubMed2000

Heisenberg, langevin, and current equations via the recurrence relations approach

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.

Journal Article↗
PubMed2000

Generalized langevin equation and recurrence relations

The generalized Langevin equation (GLE) is a reformulation of the Heisenberg equation of motion, and hence, an exact equation. It is the basis of the memory function approach, a very widely used method for studying dynamics of classical and quantum fluids. The GLE was first derived by Mori in a very formal way. A much simpler and more physically motivated derivation was given by us some years later. In this work we provide perhaps the simplest possible derivation of the GLE. The simplicity of the derivation helps to bring out the subtleties present in this important dynamical relationship.

Journal Article↗