16 papers · 1 filter
Rigidity and flexibility under positive isotropic curvature
Tsz-Kiu Aaron Chow, Yipeng Wang
For every and , we construct a smooth -PIC metric on with Urysohn -width at least and an embedded stable minimal disk of intrinsic inradius at least $L…
Nonexistence of complete metrics with uniformly positive scalar curvature
Tsz-Kiu Aaron Chow
Let be a connected oriented even-dimensional manifold whose universal cover is spin. We prove that admits no complete metric with uniformly positive scalar curvature when e…
Minimal Two-Spheres and Manifolds with Positive Isotropic Curvature
Tsz-Kiu Aaron Chow, Yipeng Wang
We improve the Micallef--Moore index estimate for harmonic two-spheres in -manifolds with positive isotropic curvature to the sharp bound . Combining with recent work, this…
Small Normal Curvature and Three-Manifold Topology
Tsz-Kiu Aaron Chow, Jingbo Wan
For , we prove that every smooth immersion satisfies , with equality only for the V…
Maximal Normal Curvature and Veronese Rigidity
Tsz-Kiu Aaron Chow, Jingbo Wan
We prove a sharp Veronese rigidity theorem for closed immersed submanifolds of the Euclidean unit ball under intrinsic harmonic-structure assumptions. For an isometric immersion $F…
Sharp focal radius estimate and rigidity of hypersurfaces in manifolds with positive curvature
Tsz-Kiu Aaron Chow, Jingbo Wan
We prove a sharp Clifford-threshold focal-radius estimate and rigidity for immersed hypersurfaces. Under a -form curvature condition, formulated by the Weitzenböck curvature ter…