Interaction Between Vortices in Models with Two Order Parameters

The interaction energy and force between widely separated strings is analyzed in a field theory having applications in many branches of physics. This field theory has two order parameters, one of which is broken in the vacuum (giving rise to strings), the other of which is unbroken in the vacuum but which could nonetheless be broken in the core of the string. If this does occur, there is an effect on the energetics of widely separated strings.