20 citations · 115 across the 45 of their papers we have counts for
4 papers · 1 filter
Differentiable classification of 4-manifolds with singular Riemannian foliations
Jianquan Ge, Marco Radeschi
In this paper, we first prove that any closed simply connected 4-manifold that admits a decomposition into two disk bundles of rank greater than 1 is diffeomorphic to one of the st…
Comparison Theorems for Manifold with Mean Convex Boundary
Jian Ge
Let be an -dimensional Riemannian manifold with boundary . Assume that Ricci curvature is bounded from below by , for $k\in \RR$, we give a sharp estim…
1/4-Pinched Contact Sphere Theorem
Jian Ge, Yang Huang
Given a closed contact 3-manifold with a compatible Riemannian metric, we show that if the sectional curvature is 1/4-pinched, then the contact structure is universally tight. This…
A note on Ribaucour transformations in Lie sphere geometry
Jianquan Ge
Following Burstall and Hertrich-Jeromin we study the Ribaucour transformation of Legendre submanifolds in Lie sphere geometry. We give an explicit parametrization of the resulted L…