
逐段单调函数的高度与拓扑共轭
Height and Topological Conjugacy of Piecewise Monotonic Functions
迭代运算下,函数值可以交叉于不同的子区间,使得逐段单调函数的高度异常复杂.本文考虑一个非单调点的连续函数类.首先给出高度的充分必要条件,以此获得此类函数的一种划分.其次针对函数类的一个非空子集,给出判定拓扑共轭的充分必要条件和构造拓扑共轭的新方法.进一步地,我们阐明这样的事实:两个逐段单调函数拓扑共轭是其高度相等的充分不必要条件,最后举例说明.
Computing height of piecewise monotonic functions is difficult because the value of functions may interact each other under iteration. In this paper we consider the set of continuous functions with a single non-monotonic point. We first present a sufficient and necessary condition for heights which gives a classification of those functions. Then we provide an equivalent condition and a new construction method for topological conjugacy for a nonempty subset of the mentioned continuous functions. Furthermore, we prove that topological conjugacy is a sufficient but not necessary condition for equal heights of piecewise monotonic functions. Finally, some examples are given to illustrate our results.
迭代 / 逐段单调函数 / 高度 / 拓扑共轭 {{custom_keyword}} /
iteration / piecewise monotonic function / height / topological conjugacy {{custom_keyword}} /
[1] Baldwin S., A complete classification of the piecewise monotone functions on the interval, Trans. Amer. Math. Soc., 1990, 319(1):155-178.
[2] Block L., Coven E. M., Topological conjugacy and transitivity for a class of piecewise monotone maps of the interval, Trans. Amer. Math. Soc., 1987, 300(1):297-306.
[3] Block L., Keesling J., Ledis D., Semi-conjugacies and inverse limit spaces, J. Difference Equ. Appl., 2012, 18(4):627-645.
[4] Cieplinski K., Zdun M. C., On uniqueness of conjugacy of continuous and piecewise monotone functions, Fixed Point Th. Appl., 2009, doi:10.1155/2009/230414.
[5] De Melo W., Van Strien S., One-Dimensional Dynamics, Springer-Verlag, Berlin, 1993.
[6] Jiang Y., Smooth classification of geometrically finite one-dimensional maps, Trans. Amer. Math. Soc., 1996, 348:2391-2412.
[7] Katok A., Hasselblatt B., Introduction to the Modern Theory of Dynamics Systems, Cambridge University Press, UK, 1995.
[8] Kuczma M., On the functional eqation φn(x)=g(x), Ann. Polon. Math., 1961, 11:161-175.
[9] Lésniak Z., Shi Y., Topological conjugacy of piecewise monotonic functions of nonmonotonicity height ≥ 1, J. Math. Anal. Appl., 2015, 423:1792-1803.
[10] Li L., A topological classification for piecewise monotone iterative roots, Aequat. Math., 2017, 91:137-152.
[11] Li L., Chen J., Iterative roots of piecewise monotonic functions with finite nonmonotonicity height, J. Math. Anal. Appl., 2014, 411:395-404.
[12] Li L., Zhang W., Conjugacy between piecewise monotonic functions and their iterative roots, Science China Mathematics, 2016, 59(2):367-378.
[13] Li S., Shen W., Smooth conjugacy between S-unimodal maps, Nonlinearity, 2006, 19:1629-1634.
[14] Liu L., Jarczyk W., Li L., et al., Iterative roots of piecewise monotonic functions of nonmonotonicity height not less than 2, Nonlinear Analysis, 2012, 75:286-303.
[15] Liu L., Zhang W., Non-monotonic iterative roots extended from characteristic intervals, J. Math. Anal. Appl., 2011, 378:359-373.
[16] Milnor J., Thurston W., On iterated maps of the interval, Dynamical Systems (College Park, MD, 1986/1987), Lecture Notes in Math., vol. 1342, Springer, Berlin, New York, 1988:465-563.
[17] Nowicki T., Przytycki F., The conjugacy of Collet-Eckmann's map of the interval with the tent map is Holder contionuous, Ergod. Th. & Dynam. Sys., 1989, 9:379-388.
[18] Parry W., Symbolic dynamics and transformations of the unit interval, Trans. Amer. Math. Soc., 1966, 122:368-378.
[19] Pierre Collet J. P. E., Iterated Maps on the Interval as Dynamical Systems, Birkhäuser, Boston, Basel, Berlin, 2009.
[20] Segawa H., Ishitani H., On the existence of a conjugacy between weakly multimodal maps, Tokyo J. Math., 1998, 21(2):511-521.
[21] Shi Y., Li L., Lésniak Z., On conjugacy of r-modal interval maps with nonmonotonicity height equal to 1, J. Difference Equ. Appl., 2013, 19:573-584.
[22] Zhang J., Yang L., Discussion on iterative roots of piecewise monotone functions (in Chinese), Acta Math. Sinica, 1983, 26:398-412.
[23] Zhang J., Yang L., Zhang W., Some advances on functional equations, Adv. Math. China., 1995, 26:385-405.
[24] Zhang W., PM functions, their characteristic intervals and iterative roots, Ann. Polon. Math., 1997, 65:119-128.
山东省自然科学基金资助项目(ZR2017MA019)
/
〈 |
|
〉 |