Morse index stability for critical points to conformally invariant Lagrangians

F Da Lio, M Gianocca, T Rivière - arXiv preprint arXiv:2212.03124, 2022 - arxiv.org
We prove the upper-semi-continuity of the Morse index plus nullity of critical points to
general conformally invariant Lagrangians in dimension 2 under weak convergence …

[HTML][HTML] Uniqueness and regularity of the fractional harmonic gradient flow in Sn− 1

J Wettstein - Nonlinear Analysis, 2022 - Elsevier
In this paper, we study the fractional harmonic gradient flow on S 1 taking values in S n− 1⊂
R n for every n≥ 2, in particular addressing uniqueness and regularity of solutions in the so …

Existence, uniqueness and regularity of the fractional harmonic gradient flow in general target manifolds

J Wettstein - arXiv preprint arXiv:2109.11458, 2021 - arxiv.org
In this paper, we continue to study the fractional harmonic gradient flow on $ S^{n-1} $ taking
values in a general closed manifold $ N\subset\mathbb {R}^ n $, addressing global …

-stability for -harmonic maps in homotopy groups

K Mazowiecka, A Schikorra - Annales de l'Institut Henri Poincaré C, 2024 - ems.press
We study s-dependence for minimizing W s; n= s-harmonic maps uW Sn! Sin homotopy
classes. Sacks–Uhlenbeck theory shows that, for each s, minimizers exist in a generating …

Distributional Fractional Gradients and a Bourgain-Brezis-type Estimate

J Wettstein - arXiv preprint arXiv:2208.07806, 2022 - arxiv.org
In this paper, we extend the definition of fractional gradients found in Mazowiecka-Schikorra
to tempered distributions on $\R^ n $, introduce associated regularisation procedures and …