A QUANTUM THERMODYNAMIC PERTURBATION STUDY OF SPIN-POLARIZED BOSON FLUIDS

With no adjustable parameters the ground-state properties of the spin- polarized bosonic fluids H(down) and T(down) are obtained via quantum thermodynamic perturbation theory. Here, perturbations are developed a round the corresponding repulsive-sphere gas. The attractive and repul sive portions of the interatomic interaction potential (Lennard-Jones and Kolos-Wolniewicz) are decomposed as proposed by Barker and Henders on and by Weeks, Chandler and Anderson. The various density series for the energy are extrapolated, order by order, to physical densities vi a Pade and related approximants. The pressure and the sound velocity c urves can be obtained from the energy. The difference between our resu lts and variational results is only significant at higher densities, w here our energy curves generally lie lower.