2025/12/18 by Lian, Yuanyuan, Pacella, Filomena, Sicbaldi, Pieralberto
Computer Science · Mathematics · #35B32 #35G15 #35N25 #Advanced Mathematical Modeling in Engineering #Analysis of PDEs (math.AP) #Contact Mechanics and Variational Inequalities #FOS: Mathematics #Nonlinear Partial Differential Equations
paper · pdf · doi:10.48550/arxiv.2512.16319
openalex publication_date 2025/12/18 · openalex created_date 2025/12/21 · openalex updated_date 2026/07/28
We study an overdetermined eigenvalue problem for domains Ω contained in the half-cylinder Σ=ω× (0, +∞), based on a bounded regular domain ω⊂ ℝN-1. It is easy to see that in any bounded cylinder Ωt=ω× (0, t), t > 0, the eigenvalue problem admits a one-dimensional positive eigenfunction which satisfies the overdetermined boundary conditions. The aim of the paper is to construct other domains Ω⊂ Σ for which there exists a positive eigenfunction that is a solution of the overdetermined problem. This is achieved by showing that branches of such domains bifurcate from the ``trivial'' domains Ωtj at the values tj = \fracπ2√(σj) where σj (j≥ 1) is a simple Neumann eigenvalue of the Laplace operator on ω⊂ ℝN-1. The solutions can be reflected with respect to ω to generate nontrivial solutions in a cylinder.