  Interactions of domain walls (DWs) are analyzed with relevance to formation
of stationary bubbles (complexes of two DWs) and complexes of many domains in
one dimensional systems. I investigate the domain structures in ferromagnets
which are described with the Landau-Lifshitz equation as well as the domains in
critical systems described with the Ginzburg-Landau equation. Supplementing
previous author studies on the creation of hard bubbles [formed by one Bloch DW
and one Neel (Ising) DW] in the presence of an external (magnetic) field, the
soft bubbles consisting of two Bloch DWs or two Neel (Ising) DWs are studied in
detail. The interactions of two DWs of the same kind are studied in the
framework of a perturbation calculus.
