{"title":"轨迹混沌","authors":"Seif Mezzi , Khadija Ben Rejeb","doi":"10.1016/j.topol.2025.109571","DOIUrl":null,"url":null,"abstract":"<div><div>Let <em>f</em> be a continuous self-map of a compact metric space <em>X</em>. Let <span><math><mi>O</mi><mo>(</mo><mi>f</mi><mo>)</mo></math></span> be the set of all trajectories under <em>f</em>, and let <em>T</em> denote its closure in the hyperspace <span><math><mi>K</mi><mo>(</mo><mi>X</mi><mo>)</mo></math></span> of all nonempty closed subsets of <em>X</em> equipped with the Hausdorff metric. The map <em>f</em> induces in a natural way a self-map <span><math><mover><mrow><mi>f</mi></mrow><mrow><mo>¯</mo></mrow></mover></math></span> on the space <em>T</em>. In this paper, we study transitivity, sensitivity, and chaos for the induced system <span><math><mo>(</mo><mi>T</mi><mo>,</mo><mover><mrow><mi>f</mi></mrow><mrow><mo>¯</mo></mrow></mover><mo>)</mo></math></span>. While we prove that this latter system can never be Devaney chaotic, we provide an example of a system <span><math><mo>(</mo><mi>X</mi><mo>,</mo><mi>f</mi><mo>)</mo></math></span> for which the associated induced system <span><math><mo>(</mo><mi>T</mi><mo>,</mo><mover><mrow><mi>f</mi></mrow><mrow><mo>¯</mo></mrow></mover><mo>)</mo></math></span> is sensitive. We study which properties are inherited between the base system <span><math><mo>(</mo><mi>X</mi><mo>,</mo><mi>f</mi><mo>)</mo></math></span> and its induced system <span><math><mo>(</mo><mi>T</mi><mo>,</mo><mover><mrow><mi>f</mi></mrow><mrow><mo>¯</mo></mrow></mover><mo>)</mo></math></span>. We prove that several known results on the hyperspaces fail to be true on the spaces of trajectories.</div></div>","PeriodicalId":51201,"journal":{"name":"Topology and its Applications","volume":"375 ","pages":"Article 109571"},"PeriodicalIF":0.5000,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Chaos of trajectories\",\"authors\":\"Seif Mezzi , Khadija Ben Rejeb\",\"doi\":\"10.1016/j.topol.2025.109571\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Let <em>f</em> be a continuous self-map of a compact metric space <em>X</em>. Let <span><math><mi>O</mi><mo>(</mo><mi>f</mi><mo>)</mo></math></span> be the set of all trajectories under <em>f</em>, and let <em>T</em> denote its closure in the hyperspace <span><math><mi>K</mi><mo>(</mo><mi>X</mi><mo>)</mo></math></span> of all nonempty closed subsets of <em>X</em> equipped with the Hausdorff metric. The map <em>f</em> induces in a natural way a self-map <span><math><mover><mrow><mi>f</mi></mrow><mrow><mo>¯</mo></mrow></mover></math></span> on the space <em>T</em>. In this paper, we study transitivity, sensitivity, and chaos for the induced system <span><math><mo>(</mo><mi>T</mi><mo>,</mo><mover><mrow><mi>f</mi></mrow><mrow><mo>¯</mo></mrow></mover><mo>)</mo></math></span>. While we prove that this latter system can never be Devaney chaotic, we provide an example of a system <span><math><mo>(</mo><mi>X</mi><mo>,</mo><mi>f</mi><mo>)</mo></math></span> for which the associated induced system <span><math><mo>(</mo><mi>T</mi><mo>,</mo><mover><mrow><mi>f</mi></mrow><mrow><mo>¯</mo></mrow></mover><mo>)</mo></math></span> is sensitive. We study which properties are inherited between the base system <span><math><mo>(</mo><mi>X</mi><mo>,</mo><mi>f</mi><mo>)</mo></math></span> and its induced system <span><math><mo>(</mo><mi>T</mi><mo>,</mo><mover><mrow><mi>f</mi></mrow><mrow><mo>¯</mo></mrow></mover><mo>)</mo></math></span>. We prove that several known results on the hyperspaces fail to be true on the spaces of trajectories.</div></div>\",\"PeriodicalId\":51201,\"journal\":{\"name\":\"Topology and its Applications\",\"volume\":\"375 \",\"pages\":\"Article 109571\"},\"PeriodicalIF\":0.5000,\"publicationDate\":\"2025-09-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Topology and its Applications\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0166864125003694\",\"RegionNum\":4,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Topology and its Applications","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0166864125003694","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
Let f be a continuous self-map of a compact metric space X. Let be the set of all trajectories under f, and let T denote its closure in the hyperspace of all nonempty closed subsets of X equipped with the Hausdorff metric. The map f induces in a natural way a self-map on the space T. In this paper, we study transitivity, sensitivity, and chaos for the induced system . While we prove that this latter system can never be Devaney chaotic, we provide an example of a system for which the associated induced system is sensitive. We study which properties are inherited between the base system and its induced system . We prove that several known results on the hyperspaces fail to be true on the spaces of trajectories.
期刊介绍:
Topology and its Applications is primarily concerned with publishing original research papers of moderate length. However, a limited number of carefully selected survey or expository papers are also included. The mathematical focus of the journal is that suggested by the title: Research in Topology. It is felt that it is inadvisable to attempt a definitive description of topology as understood for this journal. Certainly the subject includes the algebraic, general, geometric, and set-theoretic facets of topology as well as areas of interactions between topology and other mathematical disciplines, e.g. topological algebra, topological dynamics, functional analysis, category theory. Since the roles of various aspects of topology continue to change, the non-specific delineation of topics serves to reflect the current state of research in topology.
At regular intervals, the journal publishes a section entitled Open Problems in Topology, edited by J. van Mill and G.M. Reed. This is a status report on the 1100 problems listed in the book of the same name published by North-Holland in 1990, edited by van Mill and Reed.