Double field domain walls with explicit symmetry breaking

We study the dynamics of domain walls in a double-field model in which the U(1) symmetry is broken both spontaneously and explicitly. The global U(1) symmetry of the system is restored when the symmetry breaking parameter $\epsilon$ is set to zero. Two pairs of degenerate kinks exist in the model with are related to each other by a $Z_2$ transformation. We first calculate the single domain wall solutions and then investigate collision processes. These include simple scattering, pair annihilation, pair capture, and other interesting processes. The possibility of the domain wall being punctured by a string is also investigated.Comment: 15 pages, 7 figure

Fluid Dynamical Description of Sine-Gordon Solitons

We present a fluid dynamical description of a relativistic scalar field in $1+1$ dimensions and apply the general results to the special case of Sine-Gordon solitons. The results which include the local quantities pressure, density and fluid velocity are compared to the standard quantities attributed to the solitons