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arXiv · 2507.12272

Orbit sets, transitivity, and sensitivity with upper semicontinuous maps

Jeison Amorocho·Javier Camargo·Sergio Macías
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Abstract

Given a compact metric space $X$ and an upper semicontinuous function $F\colon X \to 2^X$, we explore the dynamic system $(X,F)$. In this study, we introduce new concepts, demonstrate various results, and provide numerous examples. In particular, we define the orbit set $\mathcal{O}_F(p)$ and prove that it is compact. We also establish conditions for connectedness of the orbit sets and pose several questions related to the system. We also investigate transitivity and its relation to the density of orbits. In addition, we present strong and weak notions of sensitivity and examine the relationships between these concepts.

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Jeison Amorocho, Javier Camargo, Sergio Macías. 2025-07-16. Orbit sets, transitivity, and sensitivity with upper semicontinuous maps. https://arxiv.org/abs/2507.12272

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