Abstract
We study the behaviour of extremal eigenvalues of the Dirichlet biharmonic operator over rectangles with a given fixed area. We begin by proving that the principal eigenvalue is minimal for a rectangle for which the ratio between the longest and the shortest side lengths does not exceed 1.066459. We then consider the sequence formed by the minimal kth eigenvalue and show that the corresponding sequence of minimising rectangles converges to the square as k goes to infinity.
Original language | English |
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Pages (from-to) | 1109-1120 |
Number of pages | 12 |
Journal | Proceedings of the American Mathematical Society |
Volume | 148 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2020 |
Externally published | Yes |
Keywords
- Biharmonic operator
- Eigenvalues
- Isoperimetric inequality
- Rectangles
- Shape optimisation