A refined estimate for the topological degree
Hoài-Minh Nguyên · Comptes Rendus Mathématique · 2017
We sharpen an estimate of [4] for the topological degree of continuous maps from a sphere S d 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 .