English
Related papers

Related papers: Lojasiewicz inequalities for maps of the 2-sphere

200 papers

A number of sharp inequalities are proved for the space ${\mathcal P}\left(^2D\left(\frac{\pi}{4}\right)\right)$ of 2-homogeneous polynomials on ${\mathbb R}^2$ endowed with the supremum norm on the sector…

Functional Analysis · Mathematics 2016-08-08 G. Araújo , P. Jiménez-Rodríguez , G. A. Muñoz-Fernández , J. B. Seoane-Sepúlveda

We prove several abstract versions of the Lojasiewicz-Simon gradient inequality for an analytic functional on a Banach space that generalize previous abstract versions of this inequality, weakening their hypotheses and, in particular, the…

Differential Geometry · Mathematics 2020-08-17 Paul M. N. Feehan , Manousos Maridakis

We give a new result on the well-posedness of the two-dimensional Stochastic Harmonic Map flow, whose study is motivated by the Landau-Lifshitz-Gilbert model for thermal fluctuations in micromagnetics. We construct strong solutions that…

Probability · Mathematics 2018-11-12 Antoine Hocquet

We calculate the Wess-Zumino term $\Gamma(g)$ for a harmonic map $g$ of a closed surface to a compact, simply connected, simple Lie group $G$ in terms of the energy and the holonomy of the Chern-Simons line bundle on the moduli space of…

Differential Geometry · Mathematics 2007-05-23 Nigel Hitchin

We introduce a flow of maps from a compact surface of arbitrary genus to an arbitrary Riemannian manifold which has elements in common with both the harmonic map flow and the mean curvature flow, but is more effective at finding minimal…

Differential Geometry · Mathematics 2016-05-18 Melanie Rupflin , Peter M. Topping

We relate the existence problem of harmonic maps into $S^2$ to the convex geometry of $S^2$. On one hand, this allows us to construct new examples of harmonic maps of degree 0 from compact surfaces of arbitrary genus into $S^2$. On the…

Differential Geometry · Mathematics 2019-11-05 Renan Assimos , Jürgen Jost

We show an energy convexity along any harmonic map heat flow with small initial energy and fixed boundary data on the unit 2-disk. In particular, this gives an affirmative answer to a question raised by W. Minicozzi asking whether such…

Differential Geometry · Mathematics 2018-06-18 Longzhi Lin

We establish spherical variants of the Gleason-Kahane-Zelazko and Kowalski-S{\l}odkowski theorems, and we apply them to prove that every weak-2-local isometry between two uniform algebras is a linear map. Among the consequences, we solve a…

Functional Analysis · Mathematics 2017-05-11 Lei Li , Antonio M. Peralta , Liguang Wang , Ya-Shu Wang

We construct and analyze solutions to a regularized homogeneous $p$-harmonic map flow equation for general $p \geq 2$. The homogeneous version of the problem is new and features a monotonicity formula extending the one found by Struwe for…

Analysis of PDEs · Mathematics 2023-08-31 Erik Hupp , Michał Miśkiewicz

Following the ideas of V. V. Zhikov and A. L. Pyatnitski, and more precisely the stochastic two-scale convergence, this paper establishes a homogenization theorem in a stochastic setting for two nonlinear equations : the equation of…

Analysis of PDEs · Mathematics 2019-02-18 François Alouges , Anne De Bouard , Benoît Merlet , Léa Nicolas

We consider the energy spectrum $\Xi_E(N)$ of harmonic maps from the sphere into a closed Riemannian manifold $N$. While a well known conjecture asserts that $\Xi_E(N)$ is discrete whenever $N$ is analytic, for most analytic targets it is…

Analysis of PDEs · Mathematics 2023-03-02 Melanie Rupflin

In this paper we study compactness and quantization properties of sequences of 1/2-harmonic maps $u_k\colon\R\to {\cal{S}}^{m-1}$ such that $|u_k|_{\dot H^{1/2}(\R,{\cal{S}}^{m-1})}\le C.$ More precisely we show that there exist a weak…

Analysis of PDEs · Mathematics 2012-10-10 Francesca Da Lio

Motivated by the theory of harmonic maps on Riemannian surfaces, conformal-harmonic maps between two Riemannian manifolds $M$ and $N$ were introduced in search of a natural notion of harmonicity for maps defined on a general even…

Differential Geometry · Mathematics 2025-07-08 Longzhi Lin , Jingyong Zhu

The Tomas-Stein inequality for a compact subset $\Gamma$ of the sphere $S^d$ states that the mapping $f\mapsto \widehat{f\sigma}$ is bounded from $L^2(\Gamma,\sigma)$ to $L^{2+4/d}(\R^{d+1})$. Then conditional on a strict comparison between…

Classical Analysis and ODEs · Mathematics 2026-05-26 Shuanglin Shao , Ming Wang

Carrying further work of T.A. Crawford, we show that each component of the space of harmonic maps from the $2$-sphere to complex projective $2$-space of degree $d$ and energy $4 \pi E$ is a smooth closed submanifold of the space of all…

dg-ga · Mathematics 2008-02-03 L. Lemaire , J. C. Wood

In this paper, we prove an extended version of the Minkowski Inequality, holding for any smooth bounded set $\Omega \subset \mathbb R^n$, $n\geq 3$. Our proof relies on the discovery of effective monotonicity formulas holding along the…

Analysis of PDEs · Mathematics 2021-01-05 Virginia Agostiniani , Mattia Fogagnolo , Lorenzo Mazzieri

We consider the Landau-Lifshitz equations of ferromagnetism (including the harmonic map heat-flow and Schroedinger flow as special cases) for degree m equivariant maps from R^2 to S^2. If m \geq 3, we prove that near-minimal energy…

Analysis of PDEs · Mathematics 2015-05-13 S. Gustafson , K. Nakanishi , T. -P. Tsai

Conformal harmonic maps from a 4-dimensional conformal manifold to a Riemannian manifold are maps satisfying a certain conformally invariant fourth order equation. We prove a general existence result for conformal harmonic maps, analogous…

Differential Geometry · Mathematics 2011-12-30 Olivier Biquard , Farid Madani

We derive a lower bound for energies of harmonic maps of convex polyhedra in $ \R^3 $ to the unit sphere $S^2,$ with tangent boundary conditions on the faces. We also establish that $C^\infty$ maps, satisfying tangent boundary conditions,…

Mathematical Physics · Physics 2009-11-10 A. Majumdar , J. M. Robbins , M. Zyskin

In the present paper we use twistor theory in order to solve two problems related to harmonic maps from surfaces to Euclidean spheres $\mathbb{S}^n$. First, we propose a new approach to isoperimetric inequalities based on energy index.…

Differential Geometry · Mathematics 2019-06-05 Mikhail Karpukhin