黎曼流形到伪黎曼流形的调和映照（Ⅰ）

获得了从黎曼流形到伪黎曼流形的调和映照的一个充要条件，并给出了Ｂｏｃｈｎｅｒ公式。     

黎曼流形上混合边值问题的第一特征值估计

设M为一带边界M的紧致Riemann流形,本文考虑M上的下述混合边值条件的特征值问题 (△u+v_1u=0, u/n+αu|M=0,)其中n为M的外法向单位向量,α为一正常数。     

非正截曲率的黎曼流形的微分形式谱

本文考虑在完备非紧具有非正截曲率的黎曼流形的算子Δｐ的谱性质，得到一个Ｌ２调和形式消灭定理．     

黎曼流形上不变集的分形维数估计

本文利用整体Lyapunov指数给出了光滑黎曼流形上C1-映射不变集的分形维数的上界.     

一类系数中带有幂函数和指数函数的对称微分算子的本质谱

研究了一类系数中带有幂函数和指数函数的高阶对称微分算子,给出常系数下此类微分算子的本质谱的分布,并得到对其系数加满足一定条件的相关摄动后本质谱不改变的结论.     

Sasaki流形上的Laplace算子谱

设Ｍ２ｍ＋１（Ｋ）是Ｚｎ＋１维常ψ一截面曲率Ｋ的紧致Ｓａｓａｋｉ流形，本文证明了与Ｍ２ｍ＋１（Ｋ）等谱的上同调Ｅｉｎｓｔｅｉｎ的紧致Ｓａｓａｋｉ流形必有常ψ－截面曲率Ｋ．     

加权Bergman空间上Toeplitz算子的本质谱

本文探讨加权Bergman空间Ap(φ)上Toeplitz算子,刻画了L∞(D)的使得符号在其中的Toeplitz算子的半换位子是紧算子的最大的自伴子代数Q,并计算了符号在Q中的Toeplitz算子的本质谱和Fredholm指标．     

局部对称共形平坦黎曼流形中带有平坦法丛的子流形

设M~(n p)是n p维共形平坦黎曼流形,且它的黎曼张量R_(tjkl)之共变导微▽R_(tjkl)=0,则称M~(n p)为局部对称共形平坦黎曼流形。 本文证得:若V~n(n≥2)是局部对称共形平坦黎曼流形M~(n p)的n维紧致无边子流形,它具有平坦法丛,若V~n在任一点上的截面曲率均大于T_c-t_c/2(n p-2),这里T_c、t_c分别是M~(n p)的Ricci曲率在该点的上、下确界,则V~n一定是M~(n p)的n 1维全测地子流形M~(n 1)之超曲面。     

黎曼流形上共形killing P—形式的对偶性

H.Yanamoto 在[2],[3]中有一猜想:对于任何黎曼流形 M~n,共形 Killingp-形式 u 的对偶*u 还是共形 Killing 形式。当 n=3时,这一结论的正确性由[3]给出.本文证明了对任何高维流形,结论都正确.     

局部对称的黎曼流形中的极小子流形

主要研究了局部对称的黎曼流形中的定向紧致无边极小子流形的内蕴刚性问题,利用一个矩阵不等式,得到了这类子流形的一个刚性定理．所得结果部分改进了已有的一个结论．     

关于积流形的P－形式上的Laplace算子谱

本文讨论了积流形的Ｐ－形式上Ｌａｐｌａｃｅ算子谱的唯一性问题，在紧Ｋａｃｈｌｅｒ流形乘积和紧Ｓａｓａｋｉ流形乘积的两类积流形中，ＣＰ^ｎ×ＣＰ^ｎ和Ｓ^２ｎ＋１（１）×Ｓ^２ｎ＋１（１）是Ｐ－形式上Ｌａｐｌａｃｃｅ算子谱特征。     

Wave Invariants of the Spectrum of the G-Invariant Laplacian and the Basic Spectrum of a Riemannian Foliation

Given a compact boundaryless Riemannian manifold upon which a compact Lie group G acts by isometries, recall that the G-invariant Laplacian is the restriction of the ordinary Laplacian on functions to the space of functions which are constant along the orbits of the action. By considering the wave trace of the invariant Laplacian and the connection between G manifolds and Riemannian foliations, invariants of the spectrum of the G-invariant Laplacian can be computed. These invariants include the lengths of certain geodesic arcs which are orthogonal to the principal orbits and contained in the open dense set of principal orbits are associated to the singularities of the wave trace of the G-invariant spectrum. If the action admits finite orbits, then the invariants also include the lengths of certain geodesics arcs connecting the finite orbit to itself. Under additional hypotheses, we obtain partial wave traces. As an application, a partial trace formula for Riemannian foliations with bundle-like metrics is also presented, as well as several special cases where better results are available.     

Average Growth of the Spectral Function on a Riemannian Manifold

We study average growth of the spectral function of the Laplacian on a Riemannian manifold. Two types of averaging are considered: with respect to the spectral parameter and with respect to a point on a manifold. We obtain as well related estimates of the growth of the pointwise ζ-function along vertical lines in the complex plane. Some examples and open problems regarding almost periodic properties of the spectral function are also discussed.     

Riemann流形上热半群的注记

本文讨论了Riemann流形上由Hodge-deRham算子△生成的热半群｛e^t△｝t≥0的渐近性质和L^p压缩性。     

Heat Content of a Riemannian Manifold with a Perfect Conducting Boundary

Let M be a compact smooth Riemannian manifold with smooth boundary. We establish the existence of an asymptotic series for the heat content of M with a perfect conducting boundary and show that the coefficients in the series are non-local invariants which are recursively determined by the coefficients for the series with corresponding zero Dirichlet boundary condition.     

局部对称空间中具有平行平均曲率向量的黎曼叶层的Pinching定理

本文利用Nakagawa和Takagi的计算散度的方法,求出局部对称空间中具有平行平均曲率向量的黎曼叶状结构${\cal F}$上向量场的散度,并证明了其上的整体Pinching定理.     

紧致黎曼流形上一类非线性热方程的梯度估计

In this paper,we study gradient estimates for the nonlinear heat equation ut-△u =au log u,on compact Riemannian manifold with or without boundary.We get a Hamilton type gradient estimate for the positi...     

极小子流形上Laplace算子的谱

本文讨论了Ｓ^ｎ＋ｐ（１）（或ＣＰ^ｎ＋1）中极小子流形上Ｌａｐｌａｃｅ算子的谱，证明了Ｓ^ｎ＋ｐ（１）中全测地极小子流形（或ＣＰ^ｎ＋1中Ｋａｃｈｌｅｒ超曲面）是由作用在ｑ-形式上的Ｌａｐｌａｃｅ算子的谱唯一确定．