no. 10
Mathematical analysis/Differential topology
A refined estimate for the topological degree
[Une estimée raffinée du degré topologique]
Présenté par : Haïm Brézis
Nguyen, Hoai-Minh1
1 École polytechnique fédérale de Lausanne, EPFL, SB MATHAA CAMA, Station 8, CH-1015 Lausanne, Switzerland
Comptes Rendus. Mathématique, Tome 355 (2017) no. 10, pp. 1046-1049

We sharpen an estimate of [4] for the topological degree of continuous maps from a sphere Sd into itself in the case d≥2. This provides the answer for d≥2 to a question raised by Brezis. The problem is still open for d=1.

Nous affinons une estimée du degré topologique pour des applications continues d'une sphère Sd dans elle-même dans le cas d≥2. Cela fournit la réponse pour d≥2 à une question posée par Brezis. Le problème est encore ouvert pour d=1.

Reçu le :
Accepté le :
Publié le :
DOI : 10.1016/j.crma.2017.10.007

Nguyen, Hoai-Minh 1

1 École polytechnique fédérale de Lausanne, EPFL, SB MATHAA CAMA, Station 8, CH-1015 Lausanne, Switzerland 
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Nguyen, Hoai-Minh. A refined estimate for the topological degree. Comptes Rendus. Mathématique, Tome 355 (2017) no. 10, pp. 1046-1049. doi: 10.1016/j.crma.2017.10.007

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