James Ellis Colliander and Robert L. Jerrard
The initial value problem for the Ginzburg-Landau-Schr\"odinger equation is examined in the $\epsilon \rightarrow 0$ limit under two main assumptions on the initial data $\phi^\epsilon$. The first assumption is that $\phi^\epsilon$ exhibits $m$ distinct vortices of degree $\pm 1$; these are described as points of concentration of the Jacobian $[J\phi^\epsilon]$ of $\phi^\epsilon$. Second, we assume energy bounds consistent with vortices at the points of concentration. Under these assumptions, we identify ``vortex structures'' in the $\epsilon \rightarrow 0$ limit of $\phi^\epsilon$ and show that these structures persist in the solution $u^\epsilon(t)$ of $GLS_\epsilon$. We derive ordinary differential equations which govern the motion of the vortices in the $\epsilon \rightarrow 0$ limit. The limiting system of ordinary differential equations is a Hamitonian flow governed by the renormalized energy of Bethuel, Brezis and H\'elein. Our arguments rely on results about the structural stability of vortices which are proved in a separate paper.