The aim of this paper is to discuss the recurrent and asymptotical properties in dynamical systems.In ChapterⅡ, we discuss two important invariant sets, prolongation and prolongational limit set. Let X be a locally compact metric space, for a point x∈X, we get some properties of the higher positive prolongation Dα+ (x) and higher positive prolongational limit set Jα+ (x). In general, Dα+ ( Dβ+(x))is not equal to Dα+ +β(x), but if z∈Dα+ (y)and y∈Dβ+ (x) , then there is an ordinalηsuch that z∈Dη+ (x). For a set M ? X, we also discuss the positive prolongations Dα+ (M), Du+ (M)and positive prolongational limit sets Jα+ (M), Ju+ (M), and get some relations among them. Even if M ? X is a compact set, J1+ (M)=J u+(M) may not be true. We also obtain some results about the connectedness of the prolongation and prolongational limit sets. If M ? X is connected, Dα+ (M) is compact, then Dα+ (M) is connected. If M ? X is compact and connected , Ju+ (M) is compact , then Ju+ (M) is connected. At last, we give a theorem of stability. Let a dynamical system ( X ,R,π) be positively Lyapunov stable at every point x∈X,and J1+ (ω(x))=ω(x),ω(x )≠φ,then D1+ (x) is orbit stable.ChapterⅢis devoted to the dynamical systems which are in general lack of recursiveness, and notably marked by the absence of Lagrange stable motions or Poisson stable points or non-wandering point. We give some equivalent conditions among them. Let X be a locally compact Hausdorff space, if the dynamical system ( X ,R,π) is divergent, the orbit space X Cis a T1 space. If the dynamical system ( X ,R,π)is dispersive, the orbit space X Cis a T2 space. If the dynamical system ( X ,R,π)is Lagrange unstable, and is positively Lyapunov stable on the set M = { x: Jα+ (x)≠φfor each ordinalα},then R =∪{x∈Jα+ (x):αis an ordinal}=φ. In ChapterⅣ,we discuss some problems about minimal flows. Since there always exist minimal sets in a compact Hausdorff space , and the role that the minimal set plays in dynamical systems is like that the ergodicity does in measure-preserving systems. So it is one of the most important invariant sets in dynamical systems. There are two main aspects in the studies of...
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