activity
20052009
collaborators

5 papers

math.SP2009

Gradient estimate of an eigenfunction on a compact Riemannian manifold without boundary

Yiqian Shi, Bin Xu

Let be an eigenfunction with respect to the Laplace-Beltrami operator on a compact Riemannian manifold without boundary: . We show the following…

math.DG2008

The Riemannian manifolds with boundary and large symmetry

Zhi Chen, Yiqian Shi, Bin Xu

Sixty years ago, S. B. Myers and N. E. Steenrod ({\it Ann. of Math.} {\bf 40} (1939), 400-416) showed that the isometry group of a Riemannian manifold without boundary has a struct…

math.SP2005

Asymptotic behavior of -normalized eigenfunctions of the Laplace-Beltrami operator on a closed Riemannian manifold

Bin Xu

Let be the spectral function and the unit band spectral projection operator, with respect to the Laplace-Beltrami operator $\D_M$ on a closed Riemannian manifold $…

math.DG2005

Compact Group Actions On Closed Manifolds of Non-positive Curvature

Bin Xu

A. Borel proved that, if a finite group acts effectively and continuously on a closed aspherical manifold with centerless fundamental group , then a natural homomor…

math.GT2005

The Degree of Symmetry of Certain Compact Smooth Manifolds II

Bin Xu

In this paper, we give the sharp estimates for the degree of symmetry and the semi-simple degree of symmetry of certain four dimensional fiber bundles by virtue of the rigidity the…