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arXiv · 2109.02759

Backward asymptotics in S-unimodal maps

Roberto De Leo
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Abstract

While the forward trajectory of a point in a discrete dynamical system is always unique, in general a point can have infinitely many backward trajectories. The union of the limit points of all backward trajectories through $x$ was called by M.~Hero the "special $\alpha$-limit" ($s\alpha$-limit for short) of $x$. In this article we show that there is a hierarchy of $s\alpha$-limits of points under iterations of a S-unimodal map: the size of the $s\alpha$-limit of a point increases monotonically as the point gets closer and closer to the attractor. The $s\alpha$-limit of any point of the attractor is the whole non-wandering set. This hierarchy reflects the structure of the graph of a S-unimodal map recently introduced jointly by Jim Yorke and the present author.

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Roberto De Leo. 2021-09-06. Backward asymptotics in S-unimodal maps. https://doi.org/10.1142/s0218127422300130

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