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arXiv · 2011.05509

A non-Borel special alpha-limit set in the square

Steve Jackson·Bill Mance·Samuel Roth
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Abstract

We consider the complexity of special $\alpha$-limit sets, a kind of backward limit set for non-invertible dynamical systems. We show that these sets are always analytic, but not necessarily Borel, even in the case of a surjective map on the unit square. This answers a question posed by Kolyada, Misiurewicz, and Snoha.

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Steve Jackson, Bill Mance, Samuel Roth. 2020-11-11. A non-Borel special alpha-limit set in the square. https://arxiv.org/abs/2011.05509

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