English

Finite index solutions to the Bernoulli problem in three dimensions are axially symmetric

Analysis of PDEs 2026-05-11 v1 Differential Geometry

Abstract

We show that every entire solution to the Bernoulli (or one-phase) free boundary problem with finite Morse index in R3\mathbb{R}^3 is axially symmetric. In fact, we additionally prove that the same result would follow in any dimension 4n64 \le n \le 6 in which stable entire solutions are shown to be flat.

Keywords

Cite

@article{arxiv.2605.07913,
  title  = {Finite index solutions to the Bernoulli problem in three dimensions are axially symmetric},
  author = {Xavier Fernández-Real and Enric Florit-Simon and Joaquim Serra},
  journal= {arXiv preprint arXiv:2605.07913},
  year   = {2026}
}