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arXiv · 1605.01024

On Borel semifilters

Andrea Medini
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Abstract

Building on work of van Engelen and van Mill, we show that a zero-dimensional Borel space is homeomorphic to a semifilter if and only if it is homogeneous and not locally compact. Under $\mathbf{\Sigma}^1_1$-Determinacy, this result extends to all analytic and coanalytic spaces.

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Andrea Medini. 2016-05-03. On Borel semifilters. https://arxiv.org/abs/1605.01024

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