Soliton resolution and asymptotic stability of $N$-soliton solutions for the defocusing mKdV equation with finite density type initial data

We consider the Cauchy problem for the defocusing modified Korteweg-de Vries (mKdV) equation with finite density type initial data. With the $\bar{\partial}$ generalization of the nonlinear steepest descent method of Deift and Zhou, we extrapolate the leading order approximation to the solution of mKdV for large time in the solitonic space-time region $|x/t+4|<2$, and we give bounds for the error which decay as $t\rightarrow\infty$ for a general class of initial data whose difference from the non-vanishing background possesses a fixed number of finite moments. Our results provide a verification of the soliton resolution conjecture and asymptotic stability of $N$-soliton solutions for mKdV equation with finite density type initial data.
Comment: 48 pages. arXiv admin note: substantial text overlap with arXiv:1410.6887 by other authors