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Problem with the derivation of the Navier-Stokes equation by means of Zwanzig-Mori technique. II. Calculation for instationary processes

The derivation of the Navier-Stokes equation starting from the Liouville equation using projector techniques yields a friction term which is nonlinear in the velocity. In a former paper [1] it was shown that for stationary flow the second-order part of the term is non-zero, thus leading to an incorrect formula for the equation. In the present paper, the calculation is repeated for non-stationary flow, with identical result. The question arises which details of the technique are responsible for this undesired feature.