Reports on Progress in Physics

Green functions in statistical mechanics

W. E. Parry, Roy E. Turner

Published Jan 1, 1964• 13 citations

Abstract

Thermodynamic perturbation theory is described in terms of temperature-dependent Green functions. The relationship of these functions with time-temperature-dependent Green functions and with correlation functions is discussed and some of their analytic properties are derived. The chain of coupled equations forming the equations of motion of the Green functions is derived and is written in terms of functional derivatives. Two examples of the use of Green functions, discussions of the sharpness of the Fermi surface and of neutron scattering from liquid helium, are given. The use of Green functions in the theory of relaxation phenomena is described.

DOI: 10.1088/0034-4885/27/1/302

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