Turning Borel sets into clopen sets effectively

Vassilios Gregoriades

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arXiv · 1203.6874

Turning Borel sets into clopen sets effectively

Vassilios Gregoriades

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Abstract

We present the effective version of the theorem about turning Borel sets in Polish spaces into clopen sets while preserving the Borel structure of the underlying space. We show that under some conditions the emerging parameters can be chosen in a hyperarithmetical way and using this we prove a uniformity result.

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Vassilios Gregoriades. 2012-03-30. Turning Borel sets into clopen sets effectively. https://arxiv.org/abs/1203.6874

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