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arXiv · 0710.0154

Hurewicz-like tests for Borel subsets of the plane

Dominique Lecomte
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Abstract

Let xi be a non-null countable ordinal. We study the Borel subsets of the plane that can be made $\bormxi$ by refining the Polish topology on the real line. These sets are called potentially $\bormxi$. We give a Hurewicz-like test to recognize potentially $\bormxi$ sets.

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Dominique Lecomte. 2007-09-30. Hurewicz-like tests for Borel subsets of the plane. https://arxiv.org/abs/0710.0154

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