首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到10条相似文献,搜索用时 93 毫秒
1.
For a continuous self-map T of a compact metrizable space with finite topological entropy, the order of accumulation of entropy of T is a countable ordinal that arises in the theory of entropy structure and symbolic extensions. Given any compact manifold M and any countable ordinal α, we construct a continuous, surjective self-map ofM having order of accumulation of entropy α. If the dimension of M is at least 2, then the map can be chosen to be a homeomorphism.  相似文献   

2.
We consider the infima (f) on homotopy classes of energy functionals E defined on smooth maps f: MnVk between compact connected Riemannian manifolds. If M contains a sub‐manifold L of codimension greater than the degree of E then (f) is determined by the homotopy class of the restriction of f to M \ L. Conversely if the infimum on a homotopy class of a functional of at least conformal degree vanishes then the map is trivial in homology of high degrees. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

3.
We prove that given a simply connected compact manifold M and a closed manifold N, any map in the Sobolev space W 1,2(M,N) can be approximated weakly by smooth maps between M and N. Submitted: September 2002, Final version: November 2002.  相似文献   

4.
Let (M,ω) be a symplectic manifold and G a compact Lie group that acts on M. Assume that the action of G on M is Hamiltonian. Then a G-equivariant Hamiltonian map on M induces a map on the symplectic quotient of M by G. Consider an autonomous Hamiltonian H with compact support on M, with no non-constant closed trajectory in time less than 1 and time-1 map fH. If the map fH descends to the symplectic quotient to a map Φ(fH) and the symplectic manifold M is exact and Ham(M,ω) has no short loops, we prove that the Hofer norm of the induced map Φ(fH) is bounded above by the Hofer norm of fH.  相似文献   

5.
Let f: MM be a partially hyperbolic diffeomorphism on a closed Riemannian manifold with uniformly compact center foliation. We show that if the center foliation of f is of dimension one then the topological entropy is constant on a small C1 neighborhood of f.  相似文献   

6.
Let M be a compact manifold with dimM?2. We prove that some iteration of the generic homeomorphism on M is semiconjugated to the shift map and has infinite topological entropy (Theorem 1.1).  相似文献   

7.
We prove that a map f : MN with finite p-energy, p > 2, from a complete manifold (M, á , ñ ){\left(M,\left\langle ,\right\rangle \right)} into a non-positively curved, compact manifold N is homotopic to a constant, provided the negative part of the Ricci curvature of the domain manifold is small in a suitable spectral sense. The result relies on a Liouville-type theorem for finite q-energy, p-harmonic maps under spectral assumptions.  相似文献   

8.
In this paper we prove that a (?,J)-holomorphic mapf:M→N (i.e.f *o?=Jof *) from a Trans-Sasaki manifold to a nearly Kähler manifold is a harmonic map. We also study the stability of a such map whenM is a compact Trans-Sasaki manifold andN is a Kähler manifold.  相似文献   

9.
Consider a discrete time dynamical systemx k+1=f(x k ) on a compact metric spaceM, wheref:MM is a continuous map. Leth:MB k be a continuous output function. Suppose that all of the positive orbits off are dense and that the system is observable. We prove that any output trajectory of the system determinesf andh andM up to a homeomorphism. IfM is a compact Abelian topological group andf is an ergodic translation, then any output trajectory determines the system up to a translation and a group isomorphism of the group.  相似文献   

10.
LetM be a manifold satisfying certain conditions which are weaker than those of E. Thomas[12], andf:MN be a map with codimension one or two. We give necessary and sufficient conditions forf to be homotopic to a map with maximal rank. As an application, we completely determine the codimension one or two immersions of Dold manifolds in real projective spaces.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号