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arXiv · 1609.02331

Pleijel's nodal domain theorem for Neumann and Robin eigenfunctions

Corentin Léna
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Abstract

In this paper, we show that equality in Courant's nodal domain theorem can only be reached for a finite number of eigenvalues of the Neumann Laplacian, in the case of an open, bounded and connected set in R n with a C 1,1 boundary. This result is analogous to Pleijel's nodal domain theorem for the Dirichlet Laplacian (1956). It confirms, in all dimensions, a conjecture formulated by Pleijel, which had already been solved by I. Polterovich for a two-dimensional domain with a piecewise-analytic boundary (2009). We also show that the argument and the result extend to a class of Robin boundary conditions.

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Corentin Léna. 2016-09-08. Pleijel's nodal domain theorem for Neumann and Robin eigenfunctions. https://arxiv.org/abs/1609.02331

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