Ground-State Energy Density of a Dilute Bose Gas in the Canonical Transformation

Abstract

The ground-state energy density of an interacting dilute Bose gas system is studied in the canonical transformation scheme. It is shown that the transformation scheme enables us to calculate a higher order correction of order na3 in the particle depletion and ground-state energy density of a dilute Bose gas system, which corresponds to the density fluctuation resulting from the excited states. Considering a two-body interaction only, the coefficient of the na3 term is shown to be 2(π - 8/3) for the particle depletion, and 16(π - 8/3) for the ground-state energy density. Show more