On the first Banach problem, concerning condensations of absolute $\kappa$-Borel sets onto compacta
General Topology
2024-02-23 v6
Abstract
It is consistent that the continuum be arbitrary large and no absolute -Borel set of density , , condenses onto a compact metric space. It is consistent that the continuum be arbitrary large and any absolute -Borel set of density , , containing a closed subspace of the Baire space of weight , condenses onto a compactum. In particular, applying Brian's results in model theory, we get the following unexpected result. Given any with , there is a forcing extension in which every absolute -Borel set, containing a closed subspace of the Baire space of weight , condenses onto a compactum if, and only if, .
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Cite
@article{arxiv.2209.05942,
title = {On the first Banach problem, concerning condensations of absolute $\kappa$-Borel sets onto compacta},
author = {Alexander V. Osipov},
journal= {arXiv preprint arXiv:2209.05942},
year = {2024}
}
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6 pages