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arXiv · 2510.04809

On the eigenvalues of the biharmonic operator on annuli

Davide Buoso·Riccardo Molinarolo
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Abstract

We show that the fundamental tone of the bilaplacian with Dirichlet or Navier boundary conditions on radially symmetric domains is always simple in dimension $N\ge3$. In dimension $N=2$ we show that it is simple if the inner radius is big enough.

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Davide Buoso, Riccardo Molinarolo. 2025-10-06. On the eigenvalues of the biharmonic operator on annuli. https://arxiv.org/abs/2510.04809

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