| Abstract: | A study is made of the classical limit of nonlocal hydrodynamics, describing quantum systems of many particles. The quantum-field model is not specified, it being assumed only that there are local laws governing the conservation of energy — momentum and the number of particles. Changing over to the classical limit corresponds in nonlocal hydrodynamics to the limit of slow processes and long waves. It is shown that a hydrodynamics with viscosity and self-diffusion but without heat conduction is obtained in this case because the velocity of the medium is determined in terms of the energy flux, which is natural for quantum-field systems. Heat conduction can be introduced if velocity is instead determined in terms of particle flux. Institute of Earth Physics, Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika No. 8, pp. 61–66, August, 1996. |
