In this note, we study non-uniqueness for minimizing harmonic maps from to . We show that every boundary map can be modified to a boundary map that admits multiple minimizers of the Dirichlet energy by a small -change for . 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 maps.
Dans cette note, nous étudions la non-unicité pour les applications harmoniques de dans . Nous montrons que toute application au bord peut être modifiée en une application au bord qui admet plusieurs minimiseurs de l’énergie de Dirichlet au moyen d’un petit changement pour . Ceci renforce la conclusion d’une remarque du second auteur avec Strzelecki. L’ingrédient nouveau principal est une construction d’homotopie, qui répond à une variante simplifiée d’une question difficile concernant l’existence d’un contrôle sur la norme des homotopies entre applications .
Accepted:
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DOI: 10.5802/crmath.648
Keywords: Harmonic maps, homotopy theory
Mots-clés : Applications harmoniques, théorie de l’homotopie
Antoine Detaille 1; Katarzyna Mazowiecka 2

@article{CRMATH_2024__362_G11_1357_0, author = {Antoine Detaille and Katarzyna Mazowiecka}, title = {Generic non-uniqueness of minimizing harmonic maps from a ball to a sphere}, journal = {Comptes Rendus. Math\'ematique}, pages = {1357--1364}, publisher = {Acad\'emie des sciences, Paris}, volume = {362}, year = {2024}, doi = {10.5802/crmath.648}, mrnumber = {4824932}, zbl = {07945479}, language = {en}, }
TY - JOUR AU - Antoine Detaille AU - Katarzyna Mazowiecka TI - Generic non-uniqueness of minimizing harmonic maps from a ball to a sphere JO - Comptes Rendus. Mathématique PY - 2024 SP - 1357 EP - 1364 VL - 362 PB - Académie des sciences, Paris DO - 10.5802/crmath.648 LA - en ID - CRMATH_2024__362_G11_1357_0 ER -
Antoine Detaille; Katarzyna Mazowiecka. Generic non-uniqueness of minimizing harmonic maps from a ball to a sphere. Comptes Rendus. Mathématique, Volume 362 (2024), pp. 1357-1364. doi : 10.5802/crmath.648. https://comptes-rendus.academie-sciences.fr/mathematique/articles/10.5802/crmath.648/
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