SELECTED TOPICS IN THE QUANTUM STATISTICS OF INTERACTING PARTICLES. Lectures given at the Dept. of Physics, Univ. of Washington

Leo Van Hove

Published Jan 1, 1958• 3 citations

Abstract

Quantum statistical aspects of the anharmonic crystal in equilibrium, the approach to equilibrinm, and the zero temperature properties of a conduction electron in a crystal lattice are treated. A description of the Bravais lattice without imperfections is given. The reduction of the harmonic part of H to normal modes is demonstrated. The quantum mechanical problem of the harmonic crystal is investigatad, including the effect of the anharmonic terms. Calculations of the free energy of a crystal, the lowtemperature limit, and other macroscopic quantities and microscopic averages were made. The development of a Hamiltonian for studying the equilibrium of a system composed of electrons in an insulating crysta is discussed. A rough calculation of B'. the interaction constant, is presented. The physical effects of the interaction of one electron with the photon gas are described. Diagram calculations for the partition function are presented and partial summation of diagrams is discussed. A mathematical description of the dissipation process is given, including derivation of the master equation which refers to states of the entire system. The Boltzmann equation for governing the momentum distribution of the electron as a function of time is derived. The effects of virtual emission in the electron- photon interactionsmore » were studied. (C.J.G.)« less

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