Abstract
We study the dynamics of chiral phase transition in the O(4) linear sigma model using the time-dependent variational approach with squeezed states. We show that large domains of the disoriented chiral condensate (DCC) are formed due to the combined effect of the mode-mode and the isospin-isospin correlations. Moreover, it is found that, when the mode-mode correlation is included, the DCC domain formation is accompanied by the amplification of the quantum fluctuation, which implies the squeezing of the state. Since this effect cannot be included in the mean field approximation, this mechanism of DCC domain formation is different from the parametric amplification. We also present a result of an analysis of the two-particle correlation function for the pion fields, which reflects unique nature of the squeezed states.
