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arXiv · 1903.02397

A lower density operator for the Borel algebra

Marek Balcerzak·Szymon Głab
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Abstract

We prove that the existence of a Borel lower density operator (a Borel lifting) with respect to the $\sigma$-ideal of countable sets, for an uncountable Polish space, is equivalent to the Continuum Hypothesis.

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Marek Balcerzak, Szymon Głab. 2019-02-26. A lower density operator for the Borel algebra. https://arxiv.org/abs/1903.02397

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