We introduce an equivalence relation on 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 .
On introduit une relation d'équivalence sur 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 .
Accepted:
Published online:
Haïm Brézis 1, 2; Petru Mironescu 3; Itai Shafrir 2
@article{CRMATH_2016__354_7_677_0, author = {Ha{\"\i}m Br\'ezis and Petru Mironescu and Itai Shafrir}, title = {Distances between classes of sphere-valued {Sobolev} maps}, journal = {Comptes Rendus. Math\'ematique}, pages = {677--684}, publisher = {Elsevier}, volume = {354}, number = {7}, year = {2016}, doi = {10.1016/j.crma.2016.05.001}, language = {en}, }
Haïm Brézis; Petru Mironescu; Itai Shafrir. Distances between classes of sphere-valued Sobolev maps. Comptes Rendus. Mathématique, Volume 354 (2016) no. 7, pp. 677-684. doi : 10.1016/j.crma.2016.05.001. https://comptes-rendus.academie-sciences.fr/mathematique/articles/10.1016/j.crma.2016.05.001/
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