Tunemaru Usui

Theory of Relaxation Time of the Bose-Einstein Condensate

Relaxation of the Bose-Einstein condensate to its equilibrium density is discussed in a linear approximation of deviations. In particular, a microscopic theoretical expression for the relaxation time is given, which is applicable when the time is much longer than the correlation time of the random forces acting on the condensate. The relaxation time is inversely proportional to the condensate density. The phase of the condensate also relaxes to its equilibrium value of broken symmetry in accordance with the Josephson equation.