Multi-Component Integrable Systems and Invariant Curve Flows in Certain Geometries

In this paper, multi-component generalizations to the Camassa-Holm equation, the modified Camassa-Holm equation with cubic nonlinearity are introduced. Geometric formulations to the dual version of the Schr"odinger equation, the complex Camassa-Holm equation and the multi-component modified Camassa-Holm equation are provided. It is shown that these equations arise from non-streching invariant curve flows respectively in the three-dimensional Euclidean geometry, the two-dimensional M"obius sphere and $n$-dimensional sphere ${\mathbb{S}}^n(1)$. Integrability to these systems is also studied.