无穷远点处与Schr?dinger算子相关的极细集

本文首先得到了一些新的关于锥中无穷远点处与Schr?dinger算子相关极细集的判定准则,其证明是基于对带有修改测度的Green-Sch位势在无穷远点处渐近行为的估计.接着,刻画了这类极细集的几何性质.最后,通过一个反例来说明,所得几何性质的逆命题并不成立.     

修正Green-Sch能量的构造及应用

本文通过构造锥中修正的Green-Sch能量,不仅证明了锥中稳态Schrdinger方程弱解在无穷远点处除去一个例外集后的渐近行为,而且得到了锥中无穷远点处与Schrdinger算子相关的极细集和稀薄集新的性质.     

无穷远点处与Schrdinger算子相关极细集性质的应用

设u是定义在锥中的超函数.作为无穷远点处与Schrdinger算子相关的极细集判定准则和几何性质的应用,本文证明锥中的例外集{P=(r,Θ)∈C_n(?);u(P)V(r)φ(Θ)}和{P=(r,Θ)∈C_n(?);u(P)V(r)}分别是锥中无穷远点处与Schrdinger算子相关的极细集和稀薄集当且仅当与u相关的测度满足特定的积分条件.     

半空间中一类调和函数的例外集

利用Whitney方体的相关性质, 给出了一类调和函数在半空间中无穷远点处的增长估计, 且刻画了其 例外集的几何性质. 本文推广了张艳慧和邓冠铁在半空间中的相关结果.     

锥中上调和函数的Riesz 分解定理及其应用

本文给出了锥中上调和函数的Riesz 分解定理. 同时, 得到了它在锥中无穷远点处的增长性质, 并且刻画了其例外集的几何性质. 作为应用, 我们证明了锥内次调和函数的Phragmén-Lindelöf 型定理.     

Green位势在锥中无穷远点处的增长性质

利用Whitney立方体的相关性质,不仅给出了锥中Green位势在无穷远点处的增长性质,而且证明了其例外集的覆盖定理.     

一个在无穷远点分支出八个极限环的多项式微分系统

本文研究一类高次系统无穷远点的中心条件与极限环分支问题．作者首先推出一个计算系统无穷远点奇点量的线性递推公式，并利用计算机代数系统计算出该系统在无穷远点处的前11个奇点量，从而导出无穷远点成为中心和最高阶细焦点的条件，在此基础上作者首次给出了多项式系统在无穷远点分支出8个极限环的实例。     

一类七次多项式微分系统的中心条件与赤道极限环分支

研究了一类七次系统无穷远点的中心条件与赤道极限环分支问题.通过将实系统转化为复系统研究,给出了计算无穷远点奇点量的递推公式,并在计算机上用Mathematica推导出该系统无穷远点前14个奇点量,进一步导出了无穷远点成为中心的条件和14阶细焦点的条件,在此基础上得到了七次系统无穷远点分支出12个极限环的一个实例.     

一类多项式微分系统无穷远点的中心-焦点判定

本文研究了一类七次系统无穷远点的中心-焦点判定问题.通过将实系统转化为复系统研究,给出了计算无穷远点奇点量的递推公式,并在计算机上用Mathematica推导出该系统无穷远点前十二个奇点量,进一步导出了无穷远点成为中心的条件和分别成为七阶、九阶、十二阶细焦点的条件.     

一类五次多项式系统无穷远点等时中心条件与极限环分支

研究一类五次系统无穷远点的中心、拟等时中心条件与极限环分支问题.首先通过同胚变换将系统无穷远点转化成原点,然后求出该原点的前8个奇点量,从而导出无穷远点成为中心和最高阶细焦点的条件,在此基础上给出了五次多项式系统在无穷远点分支出8个极限环的实例.同时通过一种最新算法求出无穷远点为中心时的周期常数,得到了拟等时中心的必要条件,并利用一些有效途径一一证明了条件的充分性.     

Some characterizations of minimally thin sets in a cylinder and Beurling-Dahlberg-Sjögren type theorems

This paper shows that some characterizations of minimally thin sets connected with a domain having smooth boundary and a half-space in particular can also be given for a minimally thin set at infinity of a cylinder.

     

锥中与稳态的薛定谔算子相关的广义Martin函数的控制

In this paper we show that a positive superfunction on a cone behaves regularly at infinity outside a minimally thin set associated with the stationary Schr(o|¨)dinger operator.     

Asymptotic Simplicity and Static Data

The present article considers time-symmetric initial data sets for the vacuum Einstein field equations, which are conformally related to static initial data sets in such a way that in a neighbourhood of infinity the two initial data sets have the same massless part. It is shown that for this class of data, the solutions to the regular finite initial value problem at spatial infinity for the conformal Einstein field equations extend smoothly through the critical sets where null infinity touches spatial infinity if and only if the initial data sets coincide with static data in a neighbourhood of infinity. This result highlights the special role played by static data among the class of initial data sets for the Einstein field equations whose development gives rise to a spacetime with a smooth conformal compactification at null infinity.     

The Zero Set of Fractional Brownian Motion Is a Salem Set

The existence of sets supporting a Borel measure such that its Fourier transform tends to zero at infinity can be traced back to the problem of uniqueness of trigonometric series, studied extensively by Cantor. Given \(\alpha \in (0, 1)\), Beurling asked if there exists a subset of the real line of Hausdorff dimension \(\alpha \) supporting a Borel measure whose Fourier transform converges to zero at infinity with rate \(\alpha /2\). Salem answered the question in the affirmative and such sets are now called Salem sets or rounded sets. Kahane showed that images of compact sets by fractional Brownian motion are Salem sets and this was recently extended to Gaussian random fields with stationary increments and to multi-parameter Brownian sheets. He asked if the level sets of fractional Brownian motion are also Salem sets and the problem has remained open since. This paper answers Kahane’s question in the affirmative. The argument is based on the study of oscillatory integrals with non-smooth amplitudes and new properties of the generalised Euler spiral which have independent interest.     

Local and global properties of limit sets of foliations of quasigeodesic Anosov flows

A nonsingular flow is quasigeodesic when all flow lines are efficient in measuring distances in relative homotopy classes. We analyze the quasigeodesic property for Anosov flows in -manifolds which have negatively curved fundamental group. We show that this property implies that limit sets of stable and unstable leaves (in the universal cover) vary continuously in the sphere at infinity. It also follows that the union of the limit sets of all stable (or unstable) leaves is not the whole sphere at infinity. Finally, under the quasigeodesic hypothesis we completely determine when limit sets of leaves in the universal cover can intersect. This is done by determining exactly when flow lines in the universal cover share an ideal point.

     

Boundary Harnack Principle and Martin Boundary at Infinity for Subordinate Brownian Motions

In this paper we study the Martin boundary of unbounded open sets at infinity for a large class of subordinate Brownian motions. We first prove that, for such subordinate Brownian motions, the uniform boundary Harnack principle at infinity holds for arbitrary unbounded open sets. Then we introduce the notion of κ-fatness at infinity for open sets and show that the Martin boundary at infinity of any such open set consists of exactly one point and that point is a minimal Martin boundary point.     

On the Lebesgue measure of sum-level sets for Lüroth expansion

In this paper the sum-level sets for Lüroth expansion are introduced. We prove that the Lebesgue measure of these sum-level sets decays to zero as the level tends to infinity.     

Some Supports of Fourier Transforms of Singular Measures are not Rajchman

The notion of Riesz sets tells us that a support of Fourier transform of a measure with non-trivial singular part has to be large. The notion of Rajchman sets tells us that if the Fourier transform tends to zero at infinity outside a small set, then it tends to zero even on the small set. Here we present a new angle of an old question: Whether every Rajchman set should be Riesz.     

基于模糊值Choquet积分定义集函数的S性与PGP性

针对模糊测度空间上已建立的模糊值Choquet积分,将这种积分整体看成可测空间上取值于模糊数的集函数,当模糊测度满足一般S性和PGP性时,研究了这种模糊值集函数所保持的遗传性质.