## Chapter 8

## Free Electron Theory of Metals: Part 2: Applications to Transport Properties

##### 8.1 BOLTZMANN TRANSPORT EQUATION

The Boltzmann transport equation, also known as the Boltzmann equation, is one of the most important equations of nonequilibrium statistical mechanics. This is the area of statistical mechanics that deals with systems far from thermodynamic equilibrium, for example, when there is an applied field gradient or temperature gradient on a body. If a body is left to itself without anything being done on it, it remains in a state of thermodynamic equilibrium, that is, if one takes a sample from any portion of the body and measures the physical conditions of the sample, such as temperature, pressure, velocity, density, and so on, they ...