Nondegeneracy of harmonic maps from ${\mathbb{R}}^2$ to ${\mathbb{S}}^2$

Abstract

We prove that all harmonic maps from ${\mathbb{R}}^2$ to ${\mathbb{S}}^2$ with finite energy are nondegenerate. That is, for any harmonic map $u$ from ${\mathbb{R}}^2$ to ${\mathbb{S}}^2$ of degree $m$ (in $\mathbb{Z}$), all bounded kernel maps of the linearized operator $L_u$ at $u$ are generated by these harmonic maps near $u$ and hence the real dimension of bounded kernel space of $L_u$ is $4|m|+2$.

19 pages