RP~2上二次微分系统的拓扑分类

本文定义实射影平面上二次微分系统,研究 RP~2上无公因式二次向量场的拓扑分类,我们得到它恰有五种不同的拓扑等价类.     

Locale的弱拓扑表达

本文引入了弱拓扑空间的概念,证明了locale范畴与弱拓扑空间范畴的关系类似于拓扑空间范畴与locale范畴的关系。locale范畴严格包含于弱拓扑空间范畴并且与Sober的弱拓扑空间范畴等价。     

拓扑群在连续统上的膨胀作用

本文把一个同胚的膨胀作用推广到拓扑群的情形,并研究了有限生成离散群 的膨胀作用,得到了如下结果:Z×Z不能膨胀地作用在单位闭区间I上,而自由积 Z★Z可以膨胀地作用在I上.     

全局拓扑线性化理论的推广

微分方程dx/dt=Ax f(x)(其中A的特征根实部异于零)拓扑线性化的经典结论是由Hartman与 Grobman给出的,但是他们的结论都是局部拓扑线性化,即要求同胚函数限制在原点的小邻域内．如 果要延伸到全局上的话,必须f(x)有界．本文研究了系统(1．3),证明当此系统满足适当的条件时可全 局线性化．     

全局拓扑线性化理论的推广

微分方程dx/dt=Ax+f(x)(其中A的特征根实部异于零)拓扑线性化的经典结论是由Hartman与Grobman给出的,但是他们的结论都是局部拓扑线性化,即要求同胚函数限制在原点的小邻域内.如果要延伸到全局上的话,必须f(x)有界.本文研究了系统(1.3),证明当此系统满足适当的条件时可全局线性化.     

完备格上的上拓扑和区间拓扑

对完备格 Ｌ;记ｖ（Ｌ）为 Ｌ上的上拓扑之闭集格本文证明了完备格 Ｌ为 Ｆ－分配格当且仅当映射ｓｕｐ：ｖ（Ｌ）→Ｌ为满完备格同态;若Ｌ为Ｆ－分配的Ｂｏｏｌｅ格,则Ｌ同构于某幂集格、对Ｔ１格 Ｌ,证明了下述各条件等价。（１） Ｌ同构于某幂集格;（２） Ｌ上的区间拓扑是 Ｈａｕｓｄｏｒｆｆ的;（３）是有限分离的;（４） Ｌ是连续的对马空间（Ｘ,Ｏ（Ｘ））,进一步证明了 Ｏ（Ｘ）上的区间拓扑不可能为 Ｈａｕｓｄｏｒｆｆ的,除非（Ｘ, Ｏ（Ｘ））是离散空间．     

树映射的链等价集与拓扑熵

本文讨论了树映射f的链等价集的性质,得到了f具有零拓扑熵的几个等价条件,并证明了:如果 f的一个链等价集是个无限集,那么这个链等价集的任何孤立点都是f的非周期的终于周期点.     

树映射的链等价集与拓扑熵

本文讨论了树映射f的链等价集的性质,得到了f具有零拓扑熵的几个等价条件,并证明了如果f的一个链等价集是个无限集,那么这个链等价集的任何孤立点都是f的非周期的终于周期点.     

拓扑偶的自同伦等价群

研究拓扑偶范畴中的自同伦等价群.对于同伦可结合与同伦可逆的Co-H空间X与Y,我们将在一定的条件下得到一条可裂的短正合序列:1→(?)(X)→(?)(X(?)Y)→(?)(Y)→1.     

拓扑和的自同伦等价群

如果拓扑空间X,Y的拓扑和X∨Y的自同伦等价可以对角化,则X∨Y的自同伦等价群Aut(X∨Y)可表示为它的两个子群Autx(X∨Y)与AutY(X∨y)的乘积.     

Symplectic Topology of Integrable Hamiltonian Systems, II: Topological Classification

The main purpose of this paper is to give a topological and symplectic classification of completely integrable Hamiltonian systems in terms of characteristic classes and other local and global invariants.     

Cyclic Group Action of Composite Order on Indefinite 4-manifolds

In this paper, we study the possibilities for several kinds of topological, locally linear cyclic group actions of non-prime order on some closed, simply connected 4-manifolds with indefinite intersection form. Especially, we discuss the existence of locally linear pseudofree C9 action on this kind of 4-manifolds.     

A Com binatorial Approach for Topological Classification of Graphlike M anifolds

§１．　ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｔｏｐｏｌｏｇｉｃａｌｃｌａｓｓｉｆｉｃａｔｉｏｎａｎｄｅｎｕｍｅｒａｔｉｏｎｐｒｏｂｌｅｍｏｎｇｒａｐｈｌｉｋｅｍａｎｉｆｏｌｄｓｗａｓｒａｉｓｅｄｉｎ［１］．Ｓｅｖｅｒａｌｒｅｓｕｌｔｓｗｉｔｈｒｅｓｐｅｃｔｔｏｓｐｅｃｉａｌｇｒａｐｈｌｉｋｅｍａｎｉｆｏｌｄｓｗｅｒｅｇｉｖｅｎｉｎ［１～８］．Ｗｅｓｈａｌｌｓｔｕｄｙｔｈｉｓｐｒｏｂｌｅｍｉｎａｖｉｅｗｐｏｉｎｔｏｆｐｕｒｅｃｏｍｂｉｎａｔｏｒｉｃｓ．Ｉｎｆａｃｔ，ａｎｅｗｔｙｐｅｏｆｅｎｕｍｅｒａ－ｔ…     

关于模糊拓扑环的直积

给出模糊拓扑环族直积的定义,研究它的性质,及任意模糊拓扑环族直积、与其模糊拓扑子环,与其模糊拓扑剩余环之间的同构问题.并对(QU)型模糊拓扑环关于上述问题进行研究.     

Cyclic Group Actions on 4-Manifolds

Let X be a closed, oriented Riemannian 4-manifold. Suppose that a cyclic group Z( _p (p is prime) acts on X by an orientation preserving isometry with an embedded Riemann surface as fixed point set. We study the representation of Z _p on the Spin^c-bundles and the Z _p-invariant moduli space of the solutions of the Seiberg–Witten equations for a Spin^c-structure X. When the Z _p action on the determinant bundle det L acts non-trivially on the restriction L| over the fixed point set , we consider -twisted solutions of the Seiberg-Witten equations over a Spin^c-structure ' on the quotient manifold X/Z _p X', (0,1). We relate the Z _p -invariant moduli space for the Spin^c-structure on X and the -twisted moduli space for the Spin^c-structure on X'. From this we induce a one-to-one correspondence between these moduli spaces and calculate the dimension of the -twisted moduli space. When Z _p acts trivially on L|, we prove that there is a one-to-one correspondence between the Z _p -invariant moduli space M( ^Zp and the moduli space M (") where ' is a Spin^c-structure on X' associated to the quotient bundle L/Z _p X'. vskip0pt When p = 2, we apply the above constructions to a Kahler surface X with b ₂ ⁺ (X) > 3 and H ₂(X;Z) has no 2-torsion on which an anti-holomorphic involution acts with fixed point set , a Lagrangian surface with genus greater than 0 and []2H ₂(H ;Z). If _K ^X 2 > 0 or K _X ² = 0 and the genus g()> 1, we have a vanishing theorem for Seiberg–Witten invariant of the quotient manifold X'. When K _X ² = 0 and the genus g()= 1, if there is a Z ²-equivariant Spin^c-structure on X whose virtual dimension of the Seiberg–Witten moduli space is zero then there is a Spin^c-structure " on X' such that the Seiberg-Witten invariant is ±1.     

An Ergodic Action of the Outer Automorphism Group of a Free Group

For n > 2, the action of the outer automorphism group of the rank n free group F _n on Hom(F _n , SU(2))/SU(2) is ergodic with respect to the Lebesgue measure class. The author gratefully acknowledges support from National Science Foundation grants DMS-0405605 and DMS-0103889. Received: September 2005 Revision: January 2006 Accepted: March 2006     

Topological dynamics on moduli spaces II

Let be an orientable genus 0$"> surface with boundary . Let be the mapping class group of fixing . The group acts on the space of -gauge equivalence classes of flat -connections on with fixed holonomy on . We study the topological dynamics of the -action and give conditions for the individual -orbits to be dense in .

     

关于映射同伦类的拓扑熵

设ｆ：Ｔ＾ｍ→Ｔ＾ｍ为ｍ维环面自映射，Ｎ＾∞（ｆ）是ｆ的渐近Ｎｉｅｌｓｅｎ数，本文应用Ｎｉｅｌｓｅｎ不动点理论，给出了ｌｏｇＮ＾∞（ｆ）是ｆ的同伦类的拓扑熵的最好下界的一个充要条件；并通过在齐性空间上引入等价度量，将此结论推广到了幂零流形自映射的情形。     

Topological Classification of Gradient-Like Flows with Surface Dynamics on 3-Manifolds

Mathematical Notes -