Lectures on the theory of quantum fluids

Pavel K. Kovtun

These are pedagogical lecture notes on hydrodynamic fluctuations in normal relativistic fluids. The lectures discuss correlation functions of conserved densities in thermal equilibrium, interactions of the hydrodynamic modes, an effective action for viscous fluids and the breakdown of the derivative expansion in hydrodynamics.

Léon Van Hove, Nicolaas Marinus Hugenholtz, L. P. Howland

Allan Griffin

This paper is based on three tutorial lectures given at the CRM Summer School in Banff, Alberta, June 27-July 10, 1999 on "Theoretical Physics at the End of the Twentieth Century". They will be published by Springer-Verlag. Lecture I gives a quick overview of recent studies of BEC in trapped atomic gases and reviews some properties of a trapped non-interacting Bose gas. Lecture II mainly discusses the collective modes of a pure condensate, based on the T=0 GP equation of motion. The Stringari quantum hydrodynamic theory is introduced. Lecture III discusses the coupled dynamics of the condensate and non-condensate at finite temperatures. A recent derivation of the two-fluid hydrodynamic equations is sketched. This theory predicts a new relaxational mode associated with the fact that the condensate and non-condensate may not be in diffusive equilibrium.

Alberto Bramati, Michele Modugno

亮五 久保, 文彦 高野