An isoperimetric inequality for eigenvalues of the bi-harmonic operator

Q. Ding, G. Feng, Y. Zhang

} In this article, we put forward a Neumann eigenvalue problem for the bi-harmonic operator ${\Delta }^2$ on a bounded smooth domain $\Om$ in the Euclidean $n$-space ${\mathbf{R}}^n$ ($n\ge 2$)…