{ "id": "2412.06437", "version": "v1", "published": "2024-12-09T12:26:45.000Z", "updated": "2024-12-09T12:26:45.000Z", "title": "Minimization of the first eigenvalue for the Lamé system", "authors": [ "Antoine Henrot", "Antoine Lemenant", "Yannick Privat" ], "categories": [ "math.AP", "math.SP" ], "abstract": "In this article, we address the problem of determining a domain in $\\mathbb{R}^N$ that minimizes the first eigenvalue of the Lam\\'e system under a volume constraint. We begin by establishing the existence of such an optimal domain within the class of quasi-open sets, showing that in the physically relevant dimensions $N = 2$ and $3$, the optimal domain is indeed an open set. Additionally, we derive both first and second-order optimality conditions. Leveraging these conditions, we demonstrate that in two dimensions, the disk cannot be the optimal shape when the Poisson ratio is below a specific threshold, whereas above this value, it serves as a local minimizer. We also extend our analysis to show that the disk is nonoptimal for Poisson ratios $\\nu$ satisfying $\\nu \\leq 0.4$.", "revisions": [ { "version": "v1", "updated": "2024-12-09T12:26:45.000Z" } ], "analyses": { "subjects": [ "49Q10", "47A10", "74B05", "74P10" ], "keywords": [ "first eigenvalue", "poisson ratio", "minimization", "optimal domain", "second-order optimality conditions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }