FORMATION OF VORTICES IN FIRST-ORDER PHASE-TRANSITIONS

Using a toy model Lagrangian we investigate the formation of vortices in first order phase transitions. The evolution and interactions of va cuum bubbles are also studied using both analytical approximations and a numerical simulation of scalar field dynamics. A long-lived bubble wall bound state is discovered and its existence is justified by using a simplified potential for the bubble wall interaction. The condition s that need to be satisfied for vortex formation by bubble collisions are also studied with particular emphasis placed on geometrical consid erations. These conditions are then implemented in a Monte Carlo simul ation for the study of the probability of defect formation. It is show n that the probability of vortex formation by the collision of relativ istically expanding bubbles gets reduced by about 10% due to the above -mentioned geometric effects.