English

Generic non-uniqueness of minimizing harmonic maps from a ball to a sphere

Analysis of PDEs 2026-02-17 v2

Abstract

In this note, we study non-uniqueness for minimizing harmonic maps from B3B^3 to S2\mathbb{S}^2. We show that every boundary map can be modified to a boundary map that admits multiple minimizers of the Dirichlet energy by a small W1,pW^{1,p}-change for p<2p<2. This strengthens a remark by the second-named author and Strzelecki. The main novel ingredient is a homotopy construction, which is the answer to an easier variant of a challenging question regarding the existence of a norm control for homotopies between W1,p W^{1,p} maps.

Keywords

Cite

@article{arxiv.2403.12662,
  title  = {Generic non-uniqueness of minimizing harmonic maps from a ball to a sphere},
  author = {Antoine Detaille and Katarzyna Mazowiecka},
  journal= {arXiv preprint arXiv:2403.12662},
  year   = {2026}
}

Comments

Revised version; Minor typo fixes