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arXiv · 1608.03269

Borel-piecewise continuous reducibility for uniformization problems

Takayuki Kihara
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Abstract

We study a fine hierarchy of Borel-piecewise continuous functions, especially, between closed-piecewise continuity and $G_\delta$-piecewise continuity. Our aim is to understand how a priority argument in computability theory is connected to the notion of $G_\delta$-piecewise continuity, and then we utilize this connection to obtain separation results on subclasses of $G_\delta$-piecewise continuous reductions for uniformization problems on set-valued functions with compact graphs. This method is also applicable for separating various non-constructive principles in the Weihrauch lattice.

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BibTeXRIS

Takayuki Kihara. 2016-08-10. Borel-piecewise continuous reducibility for uniformization problems. https://doi.org/10.2168/lmcs-12(4:4)2016

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