Distances between classes of sphere-valued Sobolev maps

Brézis, Haïm; Mironescu, Petru; Shafrir, Itai

doi:10.1016/j.crma.2016.05.001

Mathematical analysis

Distances between classes of sphere-valued Sobolev maps
[Distances entre classes d'applications de Sobolev à valeurs dans une sphère]

Présenté par : Haïm Brézis

Brézis, Haïm ^1,² ; Mironescu, Petru ³ ; Shafrir, Itai ²

¹ Department of Mathematics, Rutgers University, USA
² Department of Mathematics, Technion – I.I.T., 32 000 Haifa, Israel
³ Université de Lyon, Université Lyon-1, CNRS UMR 5208, Institut Camille-Jordan, 43, bd. du-11-Novembre-1918, 69622 Villeurbanne cedex, France

Comptes Rendus. Mathématique, Tome 354 (2016) no. 7, pp. 677-684.

Résumé
Abstract

On introduit une relation d'équivalence sur $W^{s, p} (S^{N}; S^{N})$ liée au degré topologique, et on présente des estimées pour les distances (au sens usuel et au sens de Hausdorff) entre les classes d'équivalence. Dans certains cas particuliers, il s'agit même de formules exactes. On considère ensuite des questions semblables pour $W^{1, p} (Ω; S^{1})$ .

We introduce an equivalence relation on $W^{s, p} (S^{N}; S^{N})$ involving the topological degree, and we evaluate the distances (in the usual sense and in the Hausdorff sense) between the equivalence classes. In some special cases, we even obtain exact formulas. Next we discuss related issues for $W^{1, p} (Ω; S^{1})$ .

Reçu le : 2016-04-23
Accepté le : 2016-04-24
Publié le : 2016-05-18

DOI : 10.1016/j.crma.2016.05.001

Affiliations des auteurs :

Brézis, Haïm ^{1, 2} ; Mironescu, Petru ³ ; Shafrir, Itai ²

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     title = {Distances between classes of sphere-valued {Sobolev} maps},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {677--684},
     publisher = {Elsevier},
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     doi = {10.1016/j.crma.2016.05.001},
     language = {en},
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Brézis, Haïm; Mironescu, Petru; Shafrir, Itai. Distances between classes of sphere-valued Sobolev maps. Comptes Rendus. Mathématique, Tome 354 (2016) no. 7, pp. 677-684. doi : 10.1016/j.crma.2016.05.001. http://www.numdam.org/articles/10.1016/j.crma.2016.05.001/

Bibliographie
Cité par

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