The Quantum Mechanics of Assemblies of Interacting Particles

The quantum mechanics of fluids at moderately high and very low temperatures is investigated by the extension of a method due to Wigner. The fundamental equation satisfied by the phase space distribution function is solved, on the basis of classical statistics, by two different methods, and quantum corrections for thermodynamical equilibrium are obtained. It is shown that the effective molecular interaction becomes very weak near absolute zero. An estimate is made of the zero-point energy. Corrections due to quantum statistics are obtained.