The pseudopotential method is used to calculate that low-lying excitation energies of a Bose gas of hard spheres at T-0 to an order beyond that previously calculated by this technique. The results are in agreement with those obtained by Beliaev using a different approach. The phonon velocity is found to be equal to the velocity of compressional waves to the order of approximation considered.

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A method based on Landau's Fermi-fluid theory is presented jot calculating the temperature-dependent viscosity q and thermal conductivity tc of a Fermi .fluid. It is argued that both O(T) and O(T 2 In T) terms appear in the temperature series expansions for r/T 2 and ~r Exact expressions for the zero-temperature limit of qT 2 and ~cT are derived for the dilute hard-sphere Fermi gas (DHSFG). The leading finite-temperature corrections to these quantities due to the s dependence of the quasiparticle scattering amplitude are also derived for the DHFSG (s is a dimensionless ratio of energy transfer to momentum transfer). The results are compared with previous expressions of Emery and of Dy and Pethick: some discrepancies are noted and discussed.