Article
Keywords:
harmonic morphisms; Kelvin transform; Weinstein operator
Summary:
The note develops results from [5] where an invariance under the Möbius transform mapping the upper halfplane onto itself of the Weinstein operator $W_k:=\Delta+\frac k{x_n}\frac{\partial}{\partial x_n}$ on $\Bbb R^n$ is proved. In this note there is shown that in the cases $k\neq 0$, $k\neq 2$ no other transforms of this kind exist and for case $k=2$, all such transforms are described.
References:
                        
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