activity
20242026
collaborators

13 papers

math.AP2026

Sharp stability for mixed bubbles on hyperbolic space

Juncheng Wei, Zetian Yan, Zhipeng Yang

We prove sharp residual stability estimates for the critical Poincaré-Sobolev equation near sums of one positive hyperbolic solution and one projected Euclidean bubble in dimension…

math.AP2026

On Dolbeault's conjecture

Juncheng Wei, Zetian Yan, Zikai Ye

We prove sharp improved Sobolev inequalities on , , for antipodally even functions and for axially symmetric functions whose critical density h…

math.DG2026

Prüfer -group and Milnor's Conjecture on Fundamental Groups

Nan Wu, Zetian Yan

We construct complete, one-ended Riemannian manifolds in dimensions four and five having strictly positive Ricci curvature, with fundamental group isomorphic to the Prüfer -grou…

math.DG2026

Nonnegative Ricci Curvature and Uniformly Convex Boundary Forces Compactness

Zetian Yan, Xingyu Zhu

We confirm a compactness conjecture of M. Li. If a complete Riemannian manifold has nonnegative Ricci curvature and uniformly convex boundary in the sense that the second fundament…

math.DG2026

Topology of 3-manifolds with nonnegative scalar curvature and positive harmonic functions

Zetian Yan, Xingyu Zhu

We study complete -manifolds with nonnegative scalar curvature under additional regularity assumptions. We prove that a contractible such manifold is diffeomorphic to $\mathbb{R…

math.DG2026

Uniqueness of the asymptotic limits for Ricci-flat manifolds with linear volume growth II

Zetian Yan, Xingyu Zhu

We relate the uniqueness of asymptotic limits for noncollapsed Ricci flat manifolds with linear volume growth to the existence of a harmonic function asymptotic to a Busemann funct…

math.AP2025

Sharp Fractional Sobolev Embeddings on Closed Manifolds

Hao Tan, Zetian Yan, Zhipeng Yang

We develop an intrinsic, heat-kernel based fractional Sobolev framework on closed Riemannian manifolds and study the critical fractional Sobolev embedding. We determine the optimal…

math.DG2025

Uniqueness of the asymptotic limits for Ricci-flat manifolds with linear volume growth

Zetian Yan, Xingyu Zhu

Under natural assumptions on curvature and cross section, we establish the uniqueness of asymptotic limits and the exponential convergence rate for complete noncollapsed Ricci flat…

math.DG2025

Energy reduction for Fourth order Willmore energy

Nan Wu, Zetian Yan

We introduce a fourth-order Willmore-type problem for closed four-dimensional submanifolds immersed in and establish a connected sum energy reduction for the general…

math.DG2024

Juhl type formulas for curved Ovsienko--Redou operators

Shane Chern, Zetian Yan

We prove Juhl type formulas for the curved Ovsienko--Redou operators and their linear analogues, which indicate the associated formal self-adjointness, thereby confirming two conje…

math.DG2024

Formal self-adjointness of a family of conformally invariant bidifferential operators

Jeffrey S. Case, Zetian Yan

We prove that the curved Ovsienko--Redou operators and a related family of differential operators are formally self-adjoint. This verifies two conjectures of Case, Lin, and Yuan.

math.DG2024

Rigidity of CMC hypersurfaces in 5-and 6-manifolds

Han Hong, Zetian Yan

We prove that nonnegative -intermediate Ricci curvature combined with uniformly positive -triRic curvature implies rigidity of complete noncompact two-sided stable minimal hy…

math.DG2024

Stable free boundary minimal hypersurfaces in locally wedge-shaped manifolds

Zetian Yan

We prove that a stable -to-edge properly embedded free boundary minimal hypersurface of a -dimensional wedge domain with angle is flat.