2019/07/29 by Csaba Farkas, Alexandru Kristály, Farkas, Csaba +3
Computer Science · Mathematics · #Advanced Mathematical Modeling in Engineering #Analysis of PDEs (math.AP) #FOS: Mathematics #Geometric Analysis and Curvature Flows #Nonlinear Partial Differential Equations #math.AP
paper · pdf · doi:10.48550/arxiv.1907.12197
7 pages
arxiv created 2019/07/29 · openalex publication_date 2019/07/29 · arxiv updated 2019/07/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Let (M,g) be an n-dimensional (n≥ 3) compact Riemannian manifold with Ric(M,g)≥ (n-1)g. If (M,g) supports an AB-type critical Sobolev inequality with Sobolev constants close to the optimal ones corresponding to the standard unit sphere (\mathbb Sn,g0), we prove that (M,g) is topologically close to (\mathbb Sn,g0). Moreover, the Sobolev constants on (M,g) are precisely the optimal constants on the sphere (\mathbb Sn,g0) if and only if (M,g) is isometric to (\mathbb Sn,g0); in particular, the latter result answers a question of V.H. Nguyen.